COLUMBIA LIBRARIES OFFSITE HEALTH SCIENCES STANDARD HXOOO 14745 Qm5L n^ Columbia (HnitJ^witp mtljeCttpoflJrttigork College of ^fjpsiiciansJ anb burgeons; Hibtavy SURGICAL Applied Anatomy, BY FEEDEEICK TEEVES, F.E.C.S., ASSISTANT SURGEON TO ANB SENIOR DEMONSTRATOR OF ANATOMY AX THE LONDON HOSPITAL; EXAMINER IN ANATOMY AT THE UNIVERSITY OF ABERDEEN ; WILSON PROFESSOR OF PATHOLOGY, ROYAL COLLEGE OF SURGEONS OF ENGLAND, 1881. ILLUSTRATED WITH 61 ENGRAVINGS. HENPtY C. L^A'S SON et CO, FMILALELPEIA, FA. M -J a TO 4iVlp 1iJrotI)cr, WILLIAM KNIGHT TKEVES, F.R.C.S., SUROKON TO TUE NATIONAL lIOSPiTAL FOB SCROFULA, MARGATE. PREFACE. Applied Anatomy has, I imagine, a twofold function. On the one hand it serves to give a precise basis to those incidents and procedures in practice that more especially involve anatomical knowledge ; on the other hand it endues the dull items of that knowledge with meaning and interest by the aid of illustrations drawn from common medical and surgical experience. In this latter aspect it bears somewhat the same relation to Systematic Anatomy that a series of ex- periments in Physics bears to a treatise dealing with the bare data of that science. The student of Human Anatomy has often a nebulous notion that what he is learning will some- time prove of service to him ; and may be conscious also that the study is a valuable, if somewhat unex- citing, mental exercise. Beyond these impressions he must regard his efforts as concerned merely in the accumulation of a number of hard unassim liable facts. viii Surgical Applied Anatomy. It should be one object of Applied Anatomy to invest these facts with the interest derived from an associa- tion with the circumstances of daily life ; it should make the dry bones live. It must be owned also that all details in Anatomy have not the same practical value, and that the memory of many of them may fade without loss to the compe- tency of the practitioner in medicine or surgery. It should be one other object, therefore, of a book, having such a purpose as the present, to assist the student in judging of the comparative value of the matter he has learnt ; and should help him, when his recollection of anatomical facts grows dim, to encourage the survival of the fittest. In writing this manual I have endeavoured, so far as the space at my command would permit, to carry out the objects above described ; and while I believe that the chief matters usually dealt with in works on Surgical Anatomy have not been neglected, I have nevertheless tried to make the principle of the book the principle that underlies Mr. Hilton's familiar lectures on "Rest and Pain." I have assumed that the reader has some know- ledge of Human Anatomy, and have not entered, except in a few instances, into any detailed anatomical Preface. ix descriptions. The bare accounts, for example, of the regions concerned in Hernia I have left to the syste- matic treatises, and have dealt only with the bearings of the anatomy of the parts upon the circumstances of practice. The limits of space have compelled me to omit all those parts of the ''Surgery of the Arteries" that deal with ligature, collateral circulation, abnor- malities, and the like. This omission I do not regret, since those subjects are fully treated not only in works on operative surgery but also in the manuals of general anatomy. The book is intended mainly for the use of students preparing for their final examination in surgery. I hope, however, that it will be of use also to practitioners whose memory of their dissecting- room work is growing a little gray, and who would wish to recall such anatomical matters as have the most direct bearing upon the details of practice. Moreover, it is possible that junior students may find some interest in the volume, and may have their studies rendered more intelligent, by learning how anatomy is concerned in actual dealings with disease. The illustrations have been executed by Mr. Charles Berjeau, F.L.S., to whose skilful pencil I am much indebted. The nicijority of them have been X Surgical Applied Anatomy. copied from familiar sources, from the works of Riidinger, Tillaux, Braiine. Agatz, aiid others. My best thanks are due to Mr. J. Macdoiiald Brown, F.R.C.S., late Demonstrator of Anatomy at the Owens College, and to Dr. James Anderson, one of the Demonstrators of Anatomy at the London Hospital, for kindly assisting me in revising the proofs, and for many valuable suggestions. Frederick Treves. 18, Gordon Square, September, 1883. CONTENTS. PART I.-THE HEAD AND NECK. CHAPTER PAGE I.— The Scalp 1 IL— TiiE Bony Vault of the Cranium . . . .12 TIL— The Cranial Contents 25 IV.— The Orbit and Evfi 33 v.— The Ear 59 VL— The Nose and Nasal Cavities 70 VII.— The Face 82 VIII.— The Mouth, Tongue, Palate, and Pharynx . 100 IX.— The Neck 118 Part ti. X.— The Thorax « * « . 14' PAR'J^ III.-THE upper EXTREMITY. XL—The Region of the Shoulder 162 XIL— The Arm 202 xii Surgical Applied Anatoi\iv. CHAPTER PAGE Xni.— The Region of the Elbow 210 XIV.— The Fork-arm .227 XV.— The Wrist and Hand 235 PART IV.-THE ABDOMEN AND PELVIS. XVI.— The Abdomen 262 XVII,— The Abdominal Viscera 295 XVIII.— The Pelvis and Perineum 334 PART V.-THE lower EXTREMITY. XIX.— The Region of the Hip 380 XX.— The Thigh 417 XXL— The Region of the Knee 424 XXII. —The Leg . 450 XXIIL— The Ankle and Foot -....,. 461 PART VI. XXiV.— The Spine 497 Index ........ t «... 516 Surgical Applied Anatomy. i3art ]F. The Head axd Neck, CHAPTER I. the scalp. The soil parts covering the vault of the skull may be divided into five layers : (1) the skin, (2) the subcutaneous fatty tissue, (3) the occipito- frontalis muscle and its aponeurosis, (4) the sub- aponeurotic connective tissue, and (5) the pericranium. It is convenient to consider the term " scalp " as limited to the structure formed by the union of the first three layers above named (Fig. 1), The skin of the scalp is thicker than it is in any other part of the body. It is in all parts intimately- — ^. f» —d ^■•-^— - -^ ■-^-^ Fig. 1.— Diagram of a Vertical Section of the Scalp. a, Skin ; b, subcutaneous tissue, with vessels: c, aponeurosis ; d, sub-aponeuro- tic tissue ; e, pericranium ; /, bone ; g, dura mater. adherent, by means of the subcutaneous tissue, to the aponeurosis and muscle beneath it, and, from this B 4 Surgical Applied Anatomy. [Chap. i. glove when it is tightly stretched over the knuckles, and those parts are sharply rapped. The scalp is extremely vascular, and presents there- fore a great resistance to sloughing and gangrenous conditions. Large flaps of a lacerated scalp,, even when extensively separated and almost cut off from the rest of the head, are more prone to live than to die. A like flap of skin^ separated from other parts of the surface, would most probably perish ; but the scalp has this advantage, that the vessels run practi- cally in the skin itself, or are, at least, in the tissue beyond the aponeurosis (Fig. 1). Thus, when a scalp flap is torn up, it still carries with it a very copious blood-supply. Bleeding from these wounds is usually very free, and often difficult to arrest. This depends, not so much upon the number of vessels in the part, as upon the density of the tissue through which these vessels run, the adherence of the outer arterial wall to the scalp structure, and the inability, therefore, of the artery to properly retract when divided. In all parts of the body where a dense bone is covered by a comparatively thin layer of soft tissues, sloughing of those tissues is apt to be induced by long and severe pressure. The scalp, by its vascu- larity, is saved to a great extent from this evil, and is much less liable to slough than are the soft parts covering such bones as the condyles of the humerus or the sacrum. But such an effect is sometimes pro- duced, as in a case I saw, where the tissues over the frontal and occipital regions sloughed from the con- tinued application of a tight bandage put on to arrest bleeding from a frontal wound. The pericranium is but slightly adherent to the bone, except at the sutures, where it is intimately united. In lacerated wounds this membrane can be readily stripped from the skull, and often, in these injuries, extensive tracts of bone are laid bare. Tlic Chap. I.] The Scalp. 5 pericranium differs somewhat in its functions from the periosteum that covers other bones. If the periosteum be removed to any extent from a bone, the part from whence it is removed will very probably perish, and necrosis from deficient blood-supply result. But the pericranium may be stripped off a considerable part of the skull vault without any necrosis, save perhaps a little superficial exfoliation, following in consequence. This is explained by the fact that the cranial bones derive their blood supply mainly from the dura mater, and are therefore to a considerable extent independent of the pericranium. A like independence cannot be claimed for the periosteum covering other bones, since that membrane brings to the part it covers a very copious and essential contribution to its blood supply. This disposition of the pericranium is also well illus- trated by its action in cases of necrosis of the cranial bones. In necrosis of a long bone, the separation of the seqxiestrum is attended with a vigorous periosteal growth of new bone, which repairs the gap left after the removal of such sequestra. In necrosis of the vault of the skull, however, no new bone is, as a rule, formed, and the gap remains unrepaired. The general indisposition of the pericranium to form new bone in other circumstances is frequently illus- trated. Abscess in the scalp region may be situated (1) above the aponeurosis, (2) between the aponeurosis and the pericranium, and (3) beneath the pericranium. Abscesses in the first situation must always be small and comparatively insignificant, since the density of the scalp tissue here is such that suppuration can only extend with the greatest difficulty. Suppuration, however, in the second situation (in the loose tissue beneath the aponeurosis) may prove very serious. The laxity of this tissue offers every inducement to the abscess to extend when once pus has found its 6 Surgical Applied Ana tomy. [Chap. i. way between tlie aponeurosis and tlie pericranium. SupjDuration in this area may undermine the entire scalp, which, in severe and unrelieved cases, may rest upon the abscess beneath as upon a kind of water- bed. As in scalp w^ounds the aponeurosis is often divided, and as suppuration may follow the injury, it will be seen that the chief danger of those lesions depends upon the spreading of such suppuration to the area of lax connective tissue now under notice. The significance of a small amount of bare bone in a scalp wound is not so much that evils will happen to the bone, but that the aponeurosis has been certainly divided, and the dangerous area of the scalp opened up. Suppuration, when it occurs in this area, is only limited by the attachments of the occipito-frontalis muscle and its aponeurosis, and therefore the most dependent places through which pus can be evacuated are along a line drawn round the head, commencing in front, above the eyebrow, passing at the side a little above the zygoma, and ending behind at the superior curved line of the occipital bone. The scalp, even when extensively dissected up by such abscesses does not peiish, since it carries, as above explained, its blood supply with it. The abscess is often very slow to close, since its walls are prevented from obtaining perfect rest by the frequent movement of the epicranial muscle. To mitigate this evil, and to ensure closing of the sinuses in obstinate cases, Mr. Hilton advises that the whole scalp be firmly secured by strapping, so that the movement of the muscle is arrested. Abscess beneath the pericranium must be limited to one bone, since the dipping-in of the membrane at the sutures prevents a more extensive spreading of the suppuration. IIsRinatoinata, or blood tumours of the scalp region, occur in the same localities as abscess. Chap. I.] The Scalp. 7 The extravasation of blood above the aponeurosis must be of a limited character, while that beneath it may be very extensive. It fortunately happens, how- ever, that the cellular tissue between the a])oneurosis and the pericranium contains but very few vessels, and hence large extravasations in this tissue are un- common. Extravasations of blood beneath the pericranium are generally termed cephalhsematomata, and are of necessity limited to one bone. They are usually con- genital, are due to pressure upon the head at birth, and are thus most commonly found over one parietal bone, that bone being probably the one most exposed to i^ressure. Their greater frequency in male children may depend upon the larger size of the head in the male fcetus. Such extravasations in early life are encouraged by the laxity of the pericranium, and by the softness and vascularity of the subjacent bone. In the temporal rcg^ioii, or the region corre- sponding to the temporal muscle, the layers of soft parts between the skin and the bone are somewhat different from those that have been already described as common to the chief part of the scalp. There is a good deal of fat in the temporal fossa, and when this is absorbed it leads to more or less prominence of the zygoma and malar bone, and so produces the project- ing " cheek bones " of the emaciated. The temporal muscle above the zygoma is covered in by a very dense fascia, the temporal fascia, which is attached above to the temporal ridge on the frontal and pari- etal bones, and below to the zygomatic arch. The unyielding nature of this fascia is well illustrated by a case recorded by Denonvilliers. It concerned a woman who had fallen in the street, and who was admitted into hospital with a deep wound in the temporal region. A piece of bone several lines in length was found loose at the bottom of the wound. 8 Surgical Applied Anatomy. [Chap. i. and was removed. After its removal the finger could be passed through an opening with an unyielding border, and came in contact with some soft substance beyond. The -case was considered to be one of com- pound fracture of the squamous bone, with separation of a fragment and exposure of the brain. A by- stander, however, noticed that the bone removed was dry and white, and a more complete examination of the wound revealed the fact that the skull was Tin- injured, that the supposed hole in the skull was merely a laceration of the temporal fascia, that the soft matter beyond was muscle and not brain, and that the fragment removed was simply a piece of bone which, lying on the ground, had been driven into the soft j)arts when the woman fell. Abscesses in the temporal fossa are prevented by the fascia from opening anywhere above the zygoma, and are encouraged rather to spread into the pterygoid and maxillary regions, and into the neck. The pericranium in the temporal region is much more adherent to the bone than it is over the rest of the vault, and subpericranial extravasations of blood are therefore practically unknown in this part of the cranial wall. Trcpliiiiing:. — This operation is frequently per- formed in the temporal region, its object being to reach extravasations of blood from the middle menin- geal artery. This artery crosses the anterior inferior angle of the parietal bone at a point 1^ inches behind the external angular process of the frontal bone, and 1| inches above the zygoma. In cutting down to the bone in the temporal region the foUowin^^c structures are met with in order : (1) The skin ; (2) branches of the superficial temporal vessels and nerves; (3) the fascia continued down from the epicranial aponeurosis ; (4) the temporal Chap. I. j The Scalp. 9 fascia ; (5) the temporal muscle ; (6) tlie deep temporal vessels; and (7) the pericranium. In trephining the skull generally, the comparative thickness of the cranial wall in various parts should be borne in mind (page 2-4), and the large arteries of the scalp should be avoided if possible. The trephine should not be applied over the frontal sinuses, which are often of large size in the aged, and should, when possible, keep clear of the sutures, owing to the frequent exit of emissary veins at or about suture lines. Especially must the superior longitudinal sinus be avoided, which runs backwards in the middle line, and the lateral sinus, whose course is represented by a line drawn horizontally from the occipital protuberance to a point about one inch behind the external meatus of the ear, where it turns downwards to groove the mas- toid process. The zygoma may be broken by direct or in- direct violence. In the latter case the violence is such as tends to thrust the upper jaw or malar bone back- wards. When due to direct violence, a fragment may be driven into the temporal muscle, and much pain caused in moving the jaw. In ordinary cases there is little or no displacement, since to both fragments the temporal fascia is attached above and the masseter below. The vessels and nerves of the scalp.— The supraorbital artery and nerve pass vertically upwards from the supraorbital notch, which is situate at the junction of the middle with the inner third of the upper orbital margin. Kearer the middle line the frontal artery and supratrochlear nerve ascend. This artery gives life to the flap that in rhinoplasty is taken from the forehead to form a new nose. The tem- poral artery, ^vith the auriculo-temporal nerve behind it, crosses the base of the zygoma just in front of the ear. The branches of this artery, especially the lo Surgical Applied Ana tomy. [Chap. i anterior brancli, are often very tortuous in the aged^ and afford early evidence of arterial degeneration. Arteriotomy is sometimes practised on the anterior brancli of this vessel. The superficial temporal vessels are very liable to be the seat of cirsoid aneurism, as, to a less extent, are the other scalp arteries. Cirsoid aneurism is more often met with in the superficial temporal arteries than in any other artery in the body. The posterior auricular artery and nerve run in the groove between the mastoid process and the ear, and the occipital artery and great occipital nerve reach the scalp just internal to a point midway between the occijDital protuberance and the mastoid process. Certain of the emissary veins are of great im- ])ortance in surgery. These veins pass through aper- tures in the cranial wall, and establish communications between the venous circulation (the sinuses) within the skull and the superficial veins external to it. The principal emissary veins are the following : 1. A vein passing through the mastoid foramen and con- necting the lateral sinus with the posterior auricular vein or with an occipital vein. This is the largest and most constant of the series. The existence of this mastoid vein serves to give an answer to the question, Why is it a co]nmon practice to aj)ply leeches and blisters behind the ear in certain cerebral affections 1 2. A vein connecting the superior longitudinal sinus with the veins of the scalp through the parietal foramen. 3. A vein connecting the lateral sinus with the deep veins at the back of the neck through the posterior condylar foramen (inconstant). 4. Minute veins following the ninth nerve through its foramen, and connecting the occij)ital sinus with the deep veins of the neck. 5. Minute veins passing through the foramen ovale, foramen lacerum and carotid canal to connect the cavernous sinus with (respectively) the Chap. I.] The Scalp. ii pterygoid venous plexuFi, tlie pliaryngeal plexus, and tlie internal jugular vein. Then, again, many minute veins connect the veins of the scalp ^vitll those of the diploe. Of the four diploic veins, two (the frontal and anterior temporal) enter into surface veins (the supraorbital and deep temporal), and two (the posterior temporal and occipital) enter jnto the lateral sinus. Lastly, there is the well-known communication between the extra- and intra-cranial venous circulation effected by the commencement of the facial vein at the inner angle of the orbit. In this communication the angular and supraorbital veins unite with the superior ophthalmic vein, a tributary of the cavernous sinus. Through these various channels, and through many probably still less conspicuous, inflammatory processes can spread from the surface to the interior of the skull. Thus we find such affections as erysipelas of the scalp, diffuse suppuration of the scalp, necrosis of the cranial bones, and the like, leading by extension to mischief within the dij^loe, to thrombosis of the sinuses, and to inflammation of the meninges of the brain. If there were no emissary veins, injuries and diseases of the scalp and skull would lose half their seriousness. Mischief may even spread from within outwards along an emissary vein. Erichsen reports a case where the lateral sinus was exposed in a com- pound fractui'e. The aperture was plugged. Throm- bosis and suppuration within the sinus followed, and some of the pus, escaping through the mastoid vein, led to an abscess in the neck. The scalp iserves, especially such as are branches of the fifth pair, are often the seat of neu- ralgia. To relieve one form of this afl'ection the supraorbital nerve has been divided (nevirotomy) at its point of exit from the orbit, and a portion of the 12 Surgical Applied Anatomy. [Chap. ii. nerve lias been resected (neurectomy) in the same situation. The lyiiipliatics from the occipital and posterior parietal regions of the scalp enter the suboccipital and mastoid glands ; those from the frontal and anterior parietal regions go to the parotid glands, while some of the vessels from the frontal region join the lymphatics of the face, and end in the submaxillary glands. CHAPTER II. THE BONY VAULT OF THE CRANIUM. Position of the sutures. — The bregma, or point of junction of the coronal and sagittal sutures, is in a line drawn vertically upwards from the external auditory meatus, the head being in normal position (Fig. 2). The lambda, or point of junction of the lambdoid and sagittal sutures, lies in the middle line, about 2j inches above the occipital protuberance. The lambdoid suture is fairly re- presented by the upper two-thirds of a line drawn from the lambda to the apex of the mastoid process on either side. The coronal suture lies along a line drawn from the bregma to the middle of the zygo- matic arch. On this line, at a spot about on a level with the external angular process of the frontal bone, and about 1^ inches behind that process, is the pterion, the region where four bones meet — the squamous bone, the great wing of the sphenoid, the frontal and parietal bones. The summit of the squa- mous suture is just two inches above the zygoma. In the normal subject all traces of the fontanelles and other unossified parts of the skull, disappear Chap. II.] Bony Vault of the Cranium. 13 before tlie age of four years. The anterior fontanelle is the last to close, while the posterior is already filled at the time of birth. It is through or about the anterior fontanelle that the ventricles are usually tapped in paracentesis in cases of hydrocephalus. In this operation the trochar is either entered at the sides Fig. 2.— The Cranial Sutures. {After Gavoy.) of the fontanelle at a sufficient distance from the middle line to avoid the sinus, or is introduced through the coronal suture at some spot other than its middle point. It may be noted that in severe hydro- cephalus the coronal and other sutures of the vault are widely opened. The condition known as cranio-tabcs, a con- dition assigned by some to rickets and by others to inherited syphilis, is usually met with in the vertical part of the occipital bone, and in the ad- jacent parts of the parietal bones. In this condition the bone is greatly thinned in spots, and its 14 Surgical Applied Anatomy. [Chap. ii. tissue so reduced that the affected district feels to the finger as if occupied by parchment, or, as some suggest, by cartridge paper. It is, on the other hand, about the site of the anterior fontanelle that certain osseous deposits are met with on the surface of the skull in some cases of hereditary syphilis (Parrot). These deposits appear as rounded elevations of porous bone situated upon the frontal and parietal bones, where they meet in the middle line. These bosses are separated by a crucial depression repre- sented by the frontal and sagittal sutures on the one hand, and the coronal suture on the other. They have been termed '^ natiform " elevations by M, Parrot, from their supposed resemblance, when viewed collectively, to the nates. To the English mind they would rather suggest the outlines of a " hot-cross bun." It is necessary to refer to the development of tUe sliiill in order to render intelligible certain con- ditions (for the most part those of congenital mal- formation) that are not unfrequently met with. Speaking generally, it may be said that the base of the skull is developed in cartilage, and the vault in membrane. The parts actually formed in membrane are represented in the completed skull by the frontal and parietal bones, the squamo-zygomatic part of the temporal bon«, and the greater part of the expanded portion of the occipital bone. The distinction between these two parts of the skull is often rendered very marked by disease. Thus there are, in the museum of the Pk^oyal College of Surgeons, the skulls of some young lions that were born in a menagerie, and that, in consequence of mal-nutrition, developed certain changes in their bones. A great part of each of these skulls shows considerable thickening, the bone being converted into a porous structure ; and it is remark- able to note that these changes are limited to such Chap. 11.] Bony Vault of the Cranium. 15 parts of the skull as are formed in membrane, the base remaining free. Among the more common of the gross mal- formations of the skull ako, is one that shows entire absence of all that part of the cranium that is formed in membrane, while the base, or cartilaginous part, is more or less perfectly developed. Meniiig'occle is the name given to a congenital tumour that consists of a protrusion of a part of the cerebral membranes through a gap in an imperfectly developed skull. When the protrusion contains brain, it is called an encephalocele, and when that pro- truded brain is distended by an accumulation of fluid within the ventricles, it is called hydrencephalocele. These protrusions are most often met with in the occipital bone, and next in frequency in the fronto- nasal suture, while in rarer cases they have been met with in the lambdoid, sagittal, and other sutures, and have projected through normal and abnormal fissures at the base of the skull into the orbit, nose, and mouth. Their frequency in the occipital bone may be in some way explained by a reference to the development of that part. This bone at birth consists of four separate parts (see Fig. 3), a basilar, two condylar, and a tabular or expanded part. In the tabular part, about the seventh week of foetal life four nuclei appear, an upper and a lower pair. These nuclei are to some extent separated by fissures running inwards from the four angles of the bone, and those that run in from the upper and lateral angles persist for some time after birth. Meningoceles of the occiput are Fig. 3.— The Occipital Bone at Birth, i6 Surgical Applied Anatomv. [Chap. ii. occur through one always in the middle line, and or other part of the vertical fissure. Since the upper part of the vertical fissure closes later than the lower part, it follows that the abnormal gap is more often above than below the occipital protuberance. If below the protuberance, the foramen magnum, may be opened up, or, on the other hand, the gap may involve the entire bone in the vertical direction. The rig. 4. — Back View of Abnormal Skulls, showing Occipital and Parietal Bones. A, The "OS epactal " ; B, parietal fissures ; c, the sagittal fontanelle. lateral fissures may persist, and may simulate fractures, for which they have, indeed, been mistaken ; or they may be so complete as to entirely separate the highest part of the occipital bone from the remainder. The bone so separated is the os epactal of the French (Fig. 4 A). Parietal fissui'es. — In the developing parietal bone, fibres concerned in ossification radiate towards the periphery from a nucleus about the centre of the Chap. II.] Bony Vault of the Cranium. 17 bone. An interfibrillar space, larger tlian the rest, is seen about the fifth month to separate the loose osseous fibres which abut .on the posterior part of the sagittal border from the stronger fibres which form the rest of this border (Pozzi), This is the lyarietal fissitre. It usually closes and leaves no trace, but it may persist in part as a suture-like fissure, and be mistaken for a fracture (Fig. 4 b). If the fissure persists equally on the two sides an elongated lozenge-shaped gap is left, the sagittal fontanelle. It is situate about an inch in front of the lambda (Fig. 4 c). Necrosis is fairly common on the vault of the skull, and most often attacks the frontal and parietal bones, while, for reasons that are not very obvious, it is rare in the occipital bone. The external table is frequently necrosed alone, it being more exposed to injury and less amply supplied with blood than is the internal table. From the converse of these reasons it happens that necrosis of the internal table alone is but rarely met with. Necrosis involving the entire thickness of the bone may prove very extensive, and in a case reported by Saviard, practically the whole of the cranial vault necrosed and came aAvay. The patient was a woman, and the primary cause of the mischief was a fall u])on the head when drunk. Fractures of the skull. — It is not easy to actually fracture the skull of a young infant. The skull as a whole at this age is imperfectly ossified, the sutures are wide, and between the bones there is much cartilage and membrane. Moreover, the bones them- selves in early life are elastic', and comparatively soft and yielding. If a blow be inflicted upon the vault in a young child the most probable efi'ect, so far as the bone itself is concerned, is an indenting or bulging in of that bone unassociated with a fracture in the ordinary sense. In this particular relation, the skull of an infant is to that of an old man as a 1 8 Surgical Applied Anatomy. [Chap. ii. cranium of thin tin would be to a cranium of strong earthenware. The yielding character of the young child's skull is well illustrated by the gross deformity of the head that certain Indian tribes produce in their offspring by applying tight bandages to the part in infancy. In the E-oyal College of Surgeons' museum are many skulls of " flat- headed " Indians, that show to what an extreme this artificial deformity may be carried. Gueniot also asserts that much deformity of the head may be produced in infants' by the practice of allowing them to always lie upon one side of the body. Here the deforming agent is simply the weight of the brain. Even in adults the skull is much less brittle than is commonly supposed, and notions as to the break- ability of the cranial bones derived from the study of the dried specimen are apt to be erroneous. During life, a sharp knife properly directed may be driven through the cranial vault so as to cause only a simple perforating wound without splintering, and without fracture of the bone beyond the puncture. Such a wound may be as cleanly cut as a wound through thick leather, and a specimen in the London Hospital museum serves well to illustrate this. A case reported in the Lancet for 1881 affords a strange instance of a knife penetrating the skull without apparently splintering the bone. A man wishing to commit suicide placed the point of a dagger against the skull in the upper frontal region, and then, drove it well into the brain by a blow from a mallet. He expected to fall dead, and was disappointed to find that no phenomena of interest developed. He then drove the dagger farther in by some dozen blows with the mallet, until the blade, which was four inches long, was brought to a standstill. The dagger was removed with great difficulty, the patient never lost conscious- ness, and recovered without a symptom. Chap. II.] Bony Vault of the Cranium. 19 The following anatomical conditions tend to minimise the efiects of violence as applied to the skull : The density of the scalp and its great mo- bility ; the dome-like arrangement of the vault ; the number of the bones that compose the head, and the tendency of the violence to be broken up amongst the many segments ; the sutures which interrupt the continuity of any given force, and the sutural mem- brane, which acts as a kind of linear buffer ; the mobility of the head upon the spine ; and the elas- ticity of the cranial bones themselves. In children the membranous layer between the sutures is of considerable thickness, but, as age advances, this membrane disappears, aud the bones tend to fuse together (synostosis). The sutures begin to be obliterated about the age of forty, the change commencing on the inner aspect of the suture, and apjDearing first in the sagittal suture, and last in the squamous, The synostosis may be complete by the age of eighty (Tillaux), and its onset is said to be coincident with the cessation of increase in the weight of the brain. This latter assertion is supported by the fact that it appears earlier in the lower races of mankind. As age advances, moreover, the skull bones become less porous, and lose much of their elasticity. They are, therefore, more readily fractured in the aged than in the young. As a rule, in fracture the entire thickness of the bone is involved ; but the external table alone may be broken, and may even be alone depressed, being driven into the diploe, or, in the case of the lower frontal region, into the frontal sinus. The internal table may be broken without a corresponding fracture in the outer plate ; and in nearly all cases of complete fracture, especially in such as are attended with depression, the internal table shows more extensive 20 Surgical Applied Anatomy. [Chap. ii. splintering than does the external. There are many- reasons for this. Tlie internal plate is not only- thinner than the external, but is so much more brittle as to receive the name of the " vitreous table." A force applied to the external table may be extremely limited, and produce, as in a sabre cut, but a limited lesion. As the force, however, travels through the diploe it becomes broken up, and reaches the inner plate as a much more diffused form of violence. This is especially the case when parts of the outer table are driven in. Then, again, the internal plate is a part of a smaller curve than is the ex- ternal plate ; and, lastly, Agnew assigns a reason for the inner plate that has reference to the general yielding of the bone. In Fig. 5, A B represents a section of a part of the vault through both tables, and c d and E F two vertical and parallel lines. Now, if force be applied to the vault between these parallel lines, the ends of the arch, A B, will tend to be- come separated, and the whole arch, yielding, will tend to assume the curve shown in Fig. 6. In such case, the lines c D and ef will converge above and diverge below (Fig. 6), so that the violence would tend to force the bone greater vulnerability of the Fig. 6. Chap. II.] Bony Vault of the Cranium. 21 particles together at the outer table and asunder at the inner table. Fractures of tlie vault are due to direct violence. The construction of the skull is such that the fracturing force is resisted in many ways. (1) When a blow is received on the vertex in the y?aWete7 region, the force tends to drive the upper borders of the two parietal bones inwards. Such driving in of these borders must be associated with a corresponding outward movement of the inferior borders. This latter movement is forcibly resisted by the squamous bone and the great wing of the sphenoid, which over- lap the lower edge of the parietal bone. Moreover, the force transmitted to the squamous bone is passed on to the zygomatic arch, which takes its support from the superior maxillary and frontal bones. This arch then acts as a second resisting buttress, and this transmission of force from the vertex to the facial bones is said to be illustrated by the pain often felt in the face after blows upon the top of the head. (2) If the upper part of the frontal bone be struck, the force is at once transmitted to the parietal bones, because the upper part of the frontal bone (owing to the manner in which its border is bevelled) actually rests upon the two parietal bones, so the same resistance is again called into action. If there be any tendency for the inferior parts of the bone to move outwards, as would certainly be the case while the mid- frontal suture existed, such movement Avould be resisted by the great wings of the sphenoid, and by the anterior inferior angles of the parietal bones which embrace or overlap these parts of the frontal. Thus it will be seen that much depends upon the manner in which the corresponding edges of the frontal and parietal bones are bevelled. (3) Blows upon the occiimt are less distinctly provided for, and it must be owned that a by no means heavy fall is sufficient to break 2 2 Surgical Applied Anatomy. [Chap. ii. this bone. It must receive, however, much protection from its connections with the two parietal and tem- poral bones, and from its articulation with the elastic vertebral column. Fractures of the base of tlie skull may be due to (1) direct or to (2) indirect violence, and, most commonly of all, to (3) extension of a fracture from the vault. (1) The base has been fractured by direct violence by foreign bodies thrust through the nasal roof, through the orbital roof, and through the base as it presents in the pharynx. The posterior fossa can also be fractured by violence applied to the nape of the neck. (2) Of fractures by indirect violence the following examples may be given : Blows applied to the lower part of the frontal bone have been associated with no lesion other than a fracture of the cribriform plate or of the orbital part of the frontal, these parts being much disposed to fracture on account of their extreme tenuity. In falls upon the chin, the condyle of the lower jaw has been so violently driven against the glenoid cavity as to fracture the middle fossa of the skull. Chassaignac gives a case where the condyle was actually thrust into the cranial cavity, and produced an abscess in the superimposed part of the brain. When the body in falling has alighted upon the feet, knees, or buttocks, the force has been trans- mitted along the vertebral column, and has led to fracture of the base in the occipital region. Such accidents are most apt to occur when the spine is kept rigid by muscular action, and the mechanism involved is precisely similar to that whereby the head of a broom is driven more firmly on to tlie broom-handle by striking the extreme end of the stick against the ground. The theory that the base is often broken by contre-coup is pretty generally abandoned, although there are a few cases that appear to support the suggestion. Such a case was recorded by Mr. Chap. II.] Bony Vault of the Cranium. 23 Hutchinson, and in it a fracture of the occipital bone was associated with a like lesion in the cribriform plate, the intervening part of the skull being un- injured. (3) Fractures of the vault, and especially linear fractures due to such diffused violence as obtains in a fall upon the head, are very apt to spread to the base. In so spi-eading they reach the base by the shortest possible route, and without any regard to the sutures encountered or to the density of the bones involved. Thus, fractures of the frontal region of the vault spread to the anterior fossa of the base, those of the parietal region to the middle fossn, and those of the occipital region to the posterior fossa. To this rule there are but few exceptions. To indicate more precisely the exact bones involved in these three districts, Mr. Hewett has divided the skull into three zones. The anterior zone includes the frontal, the upper part of the ethmoid, and the fronto-sphenoid ; the middle, the parietals, the squamous, the anterior part of the petrous portion, and the greater part of the basi-sphenoid ; and the posterior, the occipital, the mastoid, the posterior part of the petrous bone, with a small part of the body of the sphenoid. In all fractures of the base there is usually a dis- charge of blood and of cerebro-spinal fluid externally. (1) In fractures of the anterior fossa the blood usually escapes from the nose, and is derived from the menin- geal vessels, or in greater degree probably from the torn mucous lining of the nasal roof. To allow of the escape of cerebro-spinal fluid from the nose, there must be, in addition to the fracture in the nasal roof, a laceration of the mucous membrane below that fracture, and of the dura mater and arachnoid above it. In many cases of fracture in this part the blood finds its way into the orbit, and appears beneath the conjunctiva. (2) When the middle fossa is involved, the blood escapes from the external auditory meatus, 24 Surgical Applied Anatomy. [Chap. ii, through a rupture in the tympanic membrane, and is derived from the vessels of the tymj)anum and its membrane, or from an intracranial extravasation, and in some cases from a rupture of one of the sinuses about the petrous bone. The blood may follow the Eustachian tube, and may escape from the nose or mouth, or be swallowed and subsequently vomited. To allow of the escape of cerebro-spinal fluid by the ear ("the serous discharge "), (a) the fracture must have passed across the internal auditory meatus ; (b) the tubular prolongation of the membranes in that meatus must have been torn ; (c) there must be a com- munication between the internal ear and the tympa- num j and (d) the membrana tympana must have been lacerated. (3) In fractures of the posterior fossa an extravasation of blood may appear about the mastoid process or at the nape of the neck, or may even extend into the cervical region. It may be added that in compound fractures of the vault associated with tearing of the dura mater and arachnoid, an escape of cerebro-spinal fluid has in a few rai"e instances been noted, and that in cases of free serous discharge from the ear after injury to the head, but without fracture, the fluid is derived from the mastoid cells, and escapes through a rupture in the tympanic membrane. The thickness of the skull cap varies greatly, not only in different parts of the same skull, but also in corresponding parts in different individuals. The average thickness is one-fifth of an inch. The thickest parts are at the occipital protuberance (where the section may measure half an inch), the mastoid pro- cess, and the lower part of the frontal bone. The bone over tlie inferior occipital fossce is very thin, while it is thinnest over the squamous bone. Here the bone may Ijo no thicker in parts than a visiting card. The skull is also thinned over the sinuses and Chap. III.] The Cranial Contents. 25 grooves for the meningeal vessels. It is important to remember in trei:>ljining that the inner table is not always parallel with the outer. CHAPTER ITT. THE CRANIAL CONTENTS. The nieiiibraiies of the brain.— The dura mater, from its toughness, forms an excellent protec- tion to the brain. It is very intimately adherent to the bone over the whole of the base of the skull, and consequently in this situation extravasations between the membrane and the bone are scarcely possible. Over the vault its attachments are comparatively loose, although it is more closely adherent along the lines of the sutures. This lax attachment allows large h?emorr- hagic and purulent extravasations to collect between the dura mater and the bone. Such extravasations usually lead to compression of the brain, and it may be noted that in the great majority of all cases of com- pression the compressing force is outside the dura mater. Thus, in uncomplicated cases, when symptoms of compression come on at the time of an accident, the cause is probably depressed bone ; when they appear- after a short interval, the cause is probably extra v^- sated blood between the membrane and the bone ; and when a long interval (days or weeks) has elapsed after the accident, the cause is probably a collection of pus in the same situation. When blood is poured out between the dura mater and the bone in cases of fracture, the vessel that, as a rule, gives way, is the middle meningeal artery. In thirty-one cases of such haemorrhage, this vessel was 26 Surgical Applied Anatomy. [Chap. hi. the source of tlie bleeding in twenty-seven instances (P. Hewett). The artery is most often torn, as it crosses the anterior angle of the parietal bone. There are many reasons for this : the bone where grooved by the artery is very thin; the artery is often so imbedded in the bone that fracture without laceration of the vessel would hardly be possible ; and lastly, the par- ticular region of the artery is a part of the skull peculiarly liable to be fractured. Failing this vessel, the most frequent source of extra-meningeal haemorr- hage is the lateral sinus, for reasons that will be obvious. With regard to the blood sinuses formed by the dura mater, nothing remains to be added to what has been already said (page 10), except, perhaps, to observe that the relations between the internal carotid artery and cavernous sinus are so intimate that arterio-venous aneurism has followed injury involving these parts. It will be seen also with what ease this sinus could become thrombosed in cases of inflamma- tion within the orbit by the extension of the mis- chief along its great tributaries, the two ophthalmic veins. Sarcomatous growths, springing from the dura mater or other of the meninges, may make their way through the cranial bones, and project as pulsating tumours beneath the scalp. Such growths are included under the title of *' fungus of the dura mater." Between the dura mater and the arachnoid is the subdural space, formerly known as the " cavity of the arachnoid." According to Prescott Hewett, ex- travasations of blood after injury are more common in this space than in any other part within the skull. The blood so poured out may become more or less discoloured, and present in time the aspect of a thin and peculiar membrane; or the collection may form itself into a species of cyst (" arachnoid cyst ") that Chap. III.] The Cranial Contents. 27 was for some time a source of much confusion to pathologists. The subdural space contains a small amount of fluid, and acts, probably, like the pleural and peri- toneal sacs in preventing the effects of friction during the movements of the brain. The subaraclinoid space is between the arach- noid and the pia mater, and it is here that the chief part of the cerebro-spinal fluid is lodged. This space is larger in some places than in others. It is insignificant over the convexity of the brain, but is very extensive at the base of the skull in the parts beneath the cere- bellum, the medulla, the pons, and the interpeduncular space as far forwards as the optic nerves. Thus these very important parts of the brain do not rest upon bone, but rest rather on the subarachnoid collection of fluid as upon a water-bed, to use a comparison of Mr. Hilton's. The only pax't of the base of the brain that rests directly upon bone is that part in contact with the orbital plates and lesser wings of the sphe- noid. The posterior two-thirds of the brain rests upon the " water-bed," and is thus admirably pro- tected. It is well known that the brain may be damaged by contre-couix That is to say, if the head be struck at one particular part, the brain may be found unin- jured at the spot struck, but damaged at a correspond- ing place on the opposite side of the skull. The cerebro-spinal fluid is much concerned in modifying the effects of contre-coup. Thus, if the vertex be struck, the important structures at the base of the brain would be in the greatest danger of being severely injured, did they lie in actual contact with the bone. Moreover, when a blow falls upon the occiput, there may be no damage to the brain beneath the spot struck, but the yielding mass is thrown forward within the skull, and were it not for the 28 Surgical Applied Anatomy. [Chap. hi. "water-bed," the under j)arts of the cerebrum woukl be torn against the many projections in the base of the skull. As it is, the only part that usually suffers is the under surface of the frontal lobe (a compara- tively unimportant segment), which, being brought violently in contact with the irregular orbital plate, is readily contused. The subarachnoid space communi- cates with the ventricles through the foramen of Magendie. This foramen leads into the fourth ven- tricle, and is an aperture in the pia mater that closes in that ventricle. From the fourth ventricle fluid can pass along the iter into the third ventricle, and from thence to the lateral ventricles by the foramen of Monro. The cerebro-spinal fluid prevents the ill effects that irregularities in the blood circulation might have upon the brain, situate as it is within an unyielding cavity. Jf the great nerve-centres in the lateral ventricles are swollen by congestion, they are not met by an un- yielding wall, but merely displace some of the cerebro- spinal fluid through the foramen of Magendie, until such time as their circulation is normal again. Hilton has shown that closure of this foramen may lead to that excessive accumulation of fluid within the ventricles known as hydrocephalus. If the brain, too, becomes enlarged by congestion, it is not met by unyielding bone, but rather by an adjustable water-bed, and during its period of enlargement it merely displaces into the spinal 2:>art of the sub- arachnoid space some of the fluid that suiTOunds it. This mutual effect is well illustrated in a case reported by Hilton of a man with a fracture of the base, from whose ear cerebro-spinal fluid was escaping. The discharge of this fluid was at once greatly in- creased by expiratory efforts when the nose and mouth were held closed, and the veins compressed in the neck. Chap. III. The Cranial Contents. 29 The relations of the brain to the skull.— The lower level of the brain in front corresponds to a line drawn across the forehead just above the eye- brows. At the side of the head it corresponds approximately to a line drawn from a point half an inch above the external angular process of the frontal Fig. 7.- -Diagram to sliow the Relations of the Main Fissures to the Surface of the Skull, to the upper part of the external auditory meatus. A line drawn from this latter spot to the occipital pro- tuberance corresponds to the lower level of the posterior lobe, while below that line will lie the cerebellum (Fig. 7). The commencement of the Sylvian fissure corresponds to the pterion. Its ascending limb is parallel to, and immediately behind, the coronal suture. Its posterior, or horizontal limb, runs backwards across the upper margin of the squamous suture. The external parieto-occipital fissure is a little in front of the lambda. The fissure of Rolando is some way behind the coronal suture, and is not quite parallel to 30 Surgical Applied Anatomy. [Chap. in. it, being a little less than two inches behind the suture above, and a little more than one inch behind it below. The temporo-sphenoidal lobe lies below a line drawn horizontally backwards from the external angular process. To find Broca's convolution (the posterior part of the third left frontal convolution), a horizontal line is clraAvn backwards from the external angular process for two inches. The convolution is three- quarters of an inch above the end of tliis line. The upper borders of the optic thalamus and corpus striatum are about on a level with the top of the pinna. They are situate opposite the temporal region, and the antei:ior limit of the corpus striatum about corresponds to the pterion. The inotor centres on tlie cortex. — As an aid to the localisation of certain lesions of the brain, and as a means of explaining certain phenomena when the cerebral cortex is damaged, a knowledge of the cortical motor centres is most important As investigators do not agree entirely as to the exact position of these centres upon the human brain, the " cerebral localisation " of the principal authorities on this subject is here given together without comment. According to Charcot, (1) centre for movements of the tongue, at the posterior end of the third frontal conv. and contiguous part of the asc. frontal conv. \ (2) centre for movements of lower part of face, at the lower end of the two ascending convolutions ; (3) centre for fore-arm and hand, on the middle third of the asc. frontal conv. ; (4) centre for movements of the lower limb, on the upper third of the asc. frontal conv. and upper two-thirds of the asc. par. conv. According to Hitzig, (1) motor centre for upper limb, at upper part of asc. frontal conv. ; (2) motor centre for lower limb, on asc. frontal conv., just below preceding centre ; (3) motor centre Chap. III.] The Cranial Contents. 31 for facial muscles, at middle part of asc. frontal (4) centre for muscles of mouth, tongue, and conv. jaws, at inf. part of asc. frontal conv. According to Ferrier, (1) centre for rotation movements of head and neck, at post, end of first frontal conv. ; (2) centre for muscles of face, at post, end of second frontal I Fig. 8. — Skull with Parietal Bone removed, showing principal part of Cortex coucei'ned in " cerebral localisation " (G-avoy). a. Fissure of Rolando ; h, ascending frontal convolution, with, in front of it, the tliree frontal convolutions partly shown ; c, ascending parietal convolution ; c, superior parietal lobule. conv. ; (3) centre for articulate language, on post, part of third frontal conv. ; (4) centre for upi)er limb, at upper end of asc. frontal conv. ; (5) centre for lower limb, on upper two-thirds of asc. parietal conv. and part of sup. par. lobula Of the brain generally little has to be said. In a surgical sense, it presents itself simply as a large mass of soft tissue that may be damaged by shaking as gelatine may be shaken in a case. As it is of very 32 Surgical Applied Anatomy. [Chap. hi. yielding structure, and does not entirely fill the cranial cavity, it may, as it were, be thrown about within the skull, and be damage 1 by collision with its walls. Of the exact mechanism of concussion or shaking of the brain little is known, and it cannot be said that experiments, such as those of M. Gama, with a bulb of isinglass within a glass matrass, tend to throw much light upon the subject. In contusion or bruising of the brain, it is noticed that the lesion is very much more frequently situate on the under sur- face, both as regards the cerebrum and cerebellum, than on any other part (Prescott Hewett). To this statement, however, there is the striking exception that those parts of the base of the cerebrum that rest upon the large basal collection of the cerebro- spinal fluid are the least often contused. These parts include the medulla, the pons, and the interpeduncular space. The brain is very lavishly supplied with blood- vessels. The main arterial trunks (vertebral and internal carotid) are both rendered tortuous before entering the skull, with the object probably of diminishing the effects of the heart systole upon the brain. On entering, they are almost immediately blended into an anastomosing circle (circle of Willis), which has the effect of equalising the cerebral circu- lation. Ligature of one common carotid may produce no effect upon the brain, although the mortality after this operation is mainly due to cerebral complications. One carotid and the two vertebrals would appear to be able to bring enough blood to the brain, which blood will be as evenly distributed as hitherto by the circle of Willis. Both common carotids have been ligatured, or one carotid has been secured, when its fellow of the opposite side has been occluded by disease, and no marked cerebral disturbances have followed. In no case, however, has the patient recovered when the Chap. IV.] The Orbit and Eye. 33 interval between tlie closing of the two vessels was less than a few weeks. The vertebral arteries can carry a sufficient amount of blood to the brain if only the strain be thrown upon them gradually, and the brain be allowed to accommodate itself slowly to the change. Plugging of any of the smaller cerebral arteries by emboli, as a rule, leads at once to a marked disastrous result. Such embolism is met with in surgery in connection with aneurism of the common carotid. In simply examining such aneurisms, a little piece of the clot contained in the sac has been detached, has been carried up into the brain, and has produced a plugging of one of the cerebral vessels. ThuvS, hemiplegia has followed upon the mere exami- nation of a carotid aneurism, as in a case recorded by Mr. Teale, of Leeds. Fergusson's treatment of aneurism at the root of the neck, by displacing the clots by manipulation, has been abandoned on this same score. In the second case treated by manipula- tion by this surgeon, a case of subclavian aneurism, paralysis of the left side of the body followed at once upon the first handling of the tumour. CHAPTER IV. tHE ORBIT AND EYE. The orbit. — The antero-posterior diameter of the orbit is about If inches, its vertical diameter at the base a little over 1^ inches, and its horizontal diameter at the base about \\ inches. The diameters of the globe are as follows : transverse, 1 inch ; vertical and antero-posterior, both 0*96 of an inch. The eye- ball is therefore nearer to the upper and lower D 34 Surgical Applied Ana tomy. [Chap. iv. margins of the orbit than it is to the sides,, and the greatest interval between the globe and the orbital wall is on the outer side. The interior of the orbit is most conveniently reached by incisions made to the outer side of the globe, and, in excision of the eye- ball, the scissors are introduced on that side when the optic nerve has to be divided. A propos of this last matter, it may be noted that the readiest way to reach the nerve is to follow the line of the outer wall of the orbit, since a continuation of that line across the sphenoidal fissure will hit the outer rim of the foramen. -The hones forming the floor, the roof, and the inner wall of the orbital cavity, are very thin, especially in the last-named situation. Thus, foreign bodies thrust into the orbit have readily penetrated into the cranial cavity, into the nose and ethmoidal cells, and, when directed from above, into the antrum. In several instances, a sharp pointed substance, such as the end of a stick or foil, -has been thrust into the brain through the orbit, and has left but little external evidence of this serious lesion. Nelaton mentions a case in which the internal carotid artery was wounded through the orbit. A reference to the relations of the orbital walls will show that a tumour may readily invade the orbit by spreading from (1) the base of the skull, (2) from the nasal fossae, (3) from the antrum, and (4) from the temporal or zygomatic fossae. In any of these instances the gi-owth may enter the orbit by destroying the intervening thin layers of bone, and, in tumours of the antrum, this is the usual mode of entry. It may, however, extend more readily from the cranial cavity through the optic foramen or sphenoidal fissure, from the nose through the nasal duct, and from the two fossae named through the spheno-maxillary fissure. Distension of the frontal sinus by retained mucus or pus may lead to a prominent tumour at the upper and Chap. IV.] The Orbit and Eye. 35 inner margin of the orbit above the level of the tendo oculi, which may cause displacement of the globe downwards, outwards, and forwards. The bones of the orbit are peculiarly apt to be the seat of ivory exostoses, which may in time entirely occupy the orbital cavity. At the upper and outer angle of the orbit a congenital sebaceous cyst is sometimes met with. It lies beneath the orbicularis muscle, and is often con- nected at some depth with the orbital periosteum. According to most French anatomists, the orbit is divided into two distinct spaces by a process of fascia known as the capsule of Tenon. The descriptions, however, of this capsule are still of the most contra- dictory character. Viewed in its simplest aspect, it may be said to be attached all round to the margin of the base of the orbit, at which line of attachment it will be found to be connected with the orbital periosteum. It then passes backwards behind the globe, lying close to the sclerotic, and the fibres, coming from all parts of the orbital margin, meet at last at the optic nerve, with the outer sheath of which the " capsule " is continuous. As thus viewed, this fascia forms a dome for the eye-ball, and shuts it ofl from the posterior part of the orbital cavity, just as the diaphragm shuts the liver off from the thorax. It has been maintained that the capsule of Tenon has great influence upon the forward progress of orbital abscess \ but this is ditficult to understand, since, at its very best, the capsule is but a feeble membrane, lax in its attachments, and very loose in texture. It probably has but a trifling influence upon intra- orbital inflammations. Between the capsule and the sclerotic is a lymph space lined with epithelioid cells, which, with the capsule, forms a kind of socket for the globe in its movements. Tenon's capsule is pierced by the ocular muscles, to each of which it gives a process that blends with 36 Surgical Applied Anatomy. [Chap. iv. the muscle slieatli. When the insertions of the recti muscles are divided in cases of strabismus, the capsule is distinctly seen after the conjunctiva has been cut through, and requires also to be divided before the section of the muscle can be properly made. The capsule is of some importance in this procedure. After its division, the muscle does not entirely retract and lie shrunken within the orbit. Its con- nections with the capsule still give it some hold upon the globe, and still enable it to act upon that structure. Moreover, from the capsule, as it is reflected about the recti muscles, four processes are given off, one corresponding to each rectus, which are attached to the margin of the orbit. These attachments prevent the muscles from entirely retracting, and, even when the globe has been removed, they give them some basis to act upon, and thus tend to preserve some little mobility in the stump. The orbit behind Tenon's fascia is occupied by a large quantity of loose fat, in addition to the ocTilar muscles, the vessels, and nerves. It is by the absorp- tion of this fat that the sunken eye is produced in cases of emaciation and prolonged illness. This tissue affords a ready means for the spread of orbital a.1>scess. Such an abscess may follow injuries, certain ocular inflammations, periostitis, etc., or may spread from adjacent parts. The pus may occupy the entire cavity, displacing the eye-ball forwards, limit- ing its movements, and causing, by interference with the circulation, great redness of the conjunctiva and swelling of the lids. Foreign bodies, some of them of remarkable size and shape, have lodged for long periods of time in the orbital fat without causing much trouble. Thus Lawson rejDorts a case where a piece of an iron hat-peg, three inches long, was embedded in the orVjit for several days without the patient being Chap. IV.] The Orbit and Eye. 37 aware of it. A stranger case, in some ways, is that reported by Furneaux Jordan : "A man, who was employed in threshing, became the subject of severe oj:)hthahnia. At the expiration of several weeks, the patient, whilst pressing his finger on the lower eyelid, suddenly ejected from a comfortable bed of warm pus a grain of wheat, which had shot forth a vigorous gi'een sprout." The orbital fat affords also an excel- lent nidus for growing tumours. Eractures of the inner wall of the orbit involving the nasal fossse or sinuses, may lead to extensive emphysema of the orbital cellular tissue. The air so introduced may cause the globe to protrude, may limit its movements, may spread to the lids, and will, in any case, be increased in amount by blowing the nose, etc. The orbital arteries are small, and seldom give rise to trouble when divided in excising the globe, since they can be readily compressed against the bony walls of the cavity. Pulsating tumours of this part may be due to traumatic aneurisms of one of the orbital arteries, or may depend upon an arterio-venous aneurism formed between the internal carotid artery and the cavernous sinus. Pressure also upon the ophthalmic vein (as it enters the sinus), by an aneurism of the internal carotid vessel, may produce all the symptoms associated with pulsating orbital tumours. The orbital nerves may be damaged in wounds of the orbit, or in fractures of the orbit and of the base of the skull. They may be pressed upon by tumours from various parts, by aneurisms, hsemorr- hagic and inflammatory effusions. Thus Lawson re- cords a case in which the optic nerve was divided by a stab through the upper eyelid, without the globe being injured, and without any bone being fractured. The same nerve has also l^een completely torn across in fractures of the orbit, and has been pressed upon in 38 Surgical Applied Anatomy. [Chap, i v. fractures involving the lesser wing of the sphenoid. The third, fourth, and sixth nerves, and the first divi- sion of the fifth, may be affected in cases of aneurism- involving the internal carotid artery, where they lie in relation with the cavernous sinus. They may readily be pressed upon, also, by any growth involving the sphenoidal fissure, such as a periosteal node springing from the margin of the fissure, while the sixth nerve, from its more intimate connection with the base of the skull, has been directly torn across in a fracture in- volving that part (Prescott Hewett). In paralysis of tlie third nerve there is drooping of the upper lid (ptosis) ; the eye is almost motionless, presents a divergent squint from unop- posed action of the external rectus muscle, and cannot be moved either inwards, upwards, or directly down- wards. Rotation, in a direction downwards and out- wards, can still be effected by the superior oblique and outer rectus muscles. The pupil is dilated and fixed ; the power of accommodation is much imjDaired, there is diplopia, and sometimes a little protrusion of the globe from relaxation of the recti muscles. These sjanptoms refer to complete paralysis of the nerve. In cases of partial paralysis, only one or two of the above symptoms may be present. In paralysis of the fourth nerve there is often but little change to be seen, since the function of the superior oblique muscle, supplied by this nerve, may, in part, be performed vicariously. " There is usually only very slight defect in the mobility of the eye ; what there is occurs chiefly in the inner and lower angle of the field of vision ; there is deviation of the eye inwards and upwards on lowering the object, and simply upwards when it is turned far towards the healthy side". (Erb). In any case there will be diplopia, especially in certain positions of the clobe. Chap, iv.j The Orbit and Eye. 39 In paiTtlysis of tlie sixth neiTe there is con- vergent strabismus, with consequent diplopia, and an inability to rotate the eye directly outwards. In paralysis of tlielii'st division of the fifth there is a loss of sensation in all the conjunctiva, except such as covers the lower lid (supplied by the palpebral branch of the infmorbital nerve), loss of sensation in the globe, and in the skin supplied by the supratrochlear and supraorbital nerves, and in the mucous and cuta- neous surfaces supplied by the nasal nerve. No retlex movements (winking) follow upon irritation of the conjunctiva, although the patient can be made to wink on exposing the eye to a strong light, the optic nerve in this case transmitting the impression to the facial nerve. Sneezing also cannot be excited by irritating the mucous membrane in the anterior part of the nose. Destructive ulceration of the cornea may follow this paralysis, due partly to damage to the trophic branches contained in the paralysed nerve, partly to the anses- thesia which rendei-s the part readily injured, and partly to the loss of the reflex eflect of the sensory nerves upon the calibre of the blood-vessels, whereby the inflammation is permitted to go uncontrolled (Nettleship). In paralysis of the cerWeal sympathetic there is naiTOwing of the palpebral fissure from some drooping of the upper lid, apparent recession of the globe within the orbit, and some narrow- ing of the pupil from paralysis of the dilator muscle of the iris, which muscle is supplied by the sympathetic. The drooping of the upper lid may be explained by the fact that each eyelid contains a layer of unstriated muscle fibre. That in the upper lid arises from the under surface of the levator palpebr«, and is attached to the tarsal cartilage near its upper mar- gin (Fig. 11). This layer of muscle, which, when in action, would keep up the lid, is imder the influence of 40 Surgical Applied Anatomy. [Chap, i v. the cervical sympathetic. The recession of the globe is supposed by some to be due to paralysis of the orbitalis muscle of H. Miiller. This muscle bridges over the spheno-maxillary fissure, is composed o£ unstriated fibres, and is innervated by the sympathetic. Contraction of the muscle (as produced by irritation of the cervical sympathetic in animals) causes pro- trusion of the globe, while section of the sympathetic in the neck produces retraction of the eye-ball (CI. Bernard), No changes are observed in the calibre of the blood-vessels of the globe. The g"lol>e; the cornea, — The thickness of the cornea varies from -^ to ~ of an inch. One is apt to be a little deceived as to its thickness, and on introducing a knife into the cornea, the instrument, if not entered at the proper angle, may be thrust for some little distance among the laminae of the part. In front the cornea is covered by stratified epithelium. When this layer has been removed by abrasion, a white deposit of lead salts may take place in the exposed corneal tissue in cases where lead lotions are used. The bulk of the cornea is made up of a great number of fibrous lamellse, between which are anastomosing cell-spaces containing the corneal corpuscles. If the nozzle of a fine syringe be thrust into the corneal tissue, the network of cell spaces can be filled with injection (Recklinghausen's canals). When suppuration takes place within the proper corneal tissue, it is probably along these canals, modified by inflammation, that the pus spreads, thus producing onyx. The cornea contains no trace of blood-vessels, except at its extreme periphery, where the capillaries of the sclerotic and conjunctiva end in loops. This lack of a direct blood-supply renders the cornea prone to inflame spontaneously in the cachectic and ill-nourished. When inflamed, the tissue always becomes oj)aque. In the affection known as Chap. IV.] The Orbit and Eve. 41 interstitial keratitis, blood-vessels from the arteries at the margin of the cornea penetrate into the substance of the cornea for some distance. As these vessels will be some little way below the surface, and will be covered by the hazy corneal tissue that is the result of the disease, their scarlet colour is much toned down, and a sti-and of such vessels is called a " salmon patch." Tu the condition known as pannus, the cornea Fig. 9.— A Horizontal Section of the Globe throtigh. the middle. n. Cornea ; 6, sclerotic ; c, choroid ; d, retina ; e, lens ; /, iris; g, ciliary process; li, canal of Schlemm. appears to be vascularised ; but here, owing to con- tinued irritation, vessels, derived from the neighbour- ing conjunctival arteries, pass over the cornea just beneath its ephethelial covering, leaving the cornea proper as bloodless as ever. The term arcus senilis is applied to two narrow white crescents that appear at the periphery of the cornea, just within its margin, in the aged, and in certain morbid conditions. The 42 Surgical Applied Anatomy. [Chap. iv. crescents are placed at the upper and lower margins, and their points meet midway on either side of the cornea. They are due to fatty degeneration of the corneal tissue, and the change is most marked in the layers of the cornea just beneath the anterior elastic lamina, i.e., in the part most influenced by the marginal blood-vessels. In sjDite of its lack of a direct blood- supply, wounds of the cornea heal kindly. The cornea is very lavishly supplied ^vT.th nerves, estimated to be from forty to forty-five in number. They are derived from the ciliary nerves, enter the cornea through the fore part of the sclerotic, and are dis- tributed to every part of the tunic. In glaucoma, a disease the phenomena of which depend upon greatly increased intraocular pressure, the cornea becomes anaesthetic. This depends upon the pressure to which the ciliary nerves are exposed before their branches reach the cornea. (;S'ee also Nerve supj)ly of the eye- ball, page 47.) The sclerotic, clioroicl, and iris. — The sclerotic is thickest behind, and thinnest about a quarter of an inch from the cornea. When the globe is ruptured by violence it is the sclerotic that most commonly yields, the rent being most usually a little way from the cornea, i.e., in or about the thinnest part of the ttinic. A rupture of the cornea alone from violence is not common. The sclerotic may be ruptured wdiile the lax conjunctiva over it remains untorn. In such a case the lens may escape through the rent in the sclerotic, and be found under the conjunctiva. It is mainly to the denseness and unyielding character of the sclerotic that must be ascribed the severe pain (due to pressure on nerves) experienced in those eye affections associated with increased intraocular tension (glaucoma, etc.). The choroid is the vascular tunic of the globe, and carries its main blood-vessels. Between the choroid and sclerotic are two thin membranes, the lamina Chap. IV.] The Orbit and Eye, 43 suprachoroidea and lamina fusca, which are separated from one another by a lymph space. In injuries to the globe, therefore, extensive bleeding may take place between these two coats, and indeed a like hremorr- liage may be the result simply of a sudden diminution in the ocular tension produced by such an operation as iridectomy or cataract extraction. The choroid alone has been ruptured (usually at its posterior part) as the result of a blow upon the front of the eye. The choroid is one of the few parts of the body that may be the seat of melanotic growths. These growths are sarcomatous tumours containing a large amount of pigment, and occur only where pigment cells are found. In the choroid coat pigment cells are very abundant. The ii-is is, from its great vascularity, very easily inflamed. From its relations to the cornea and sclerotic it happens that inflammation in those tunics can spread without difficulty to the iris. On the other hand, the vessels of the iris and choroid are so intimately related that inflammations set up in the iris itself have every inducement to spread to the choroidal tunic. When the iris is inflamed its colour becomes altered, owing to the congestion of the part and to the effusion of lymph and serum that takes place in its substance. The swelling to which it becomes subject, together with the effusion, produce a blurring of its delicate reticulated structure, as seen through the cornea. Owing also to the swollen con- dition of the little membrane, the pupil becomes encroached on, and appears to be contracted, while the movements of the membrane are necessarily rendered very sluggish. If it be remembered that the greater part of the posterior surface of the iris is in actual contact Avith the lens capsule, it will be understood that inflammatory adhesions may readily take place between the tM^o parts (Fig. 10). After iritis, therefore, it is common to find the posterior surface of the iris 44 Surgical Applied Aatatomv. [Chap, i v. (most often its pupillary margin) adherent to the lens capsule by bands of lymph, either entirely or in one or more different points. Such adhesions constitute posterior synechias, the term anterior synechise being applied to adhesions between the iris and the cornea. In iritis also the lens may become involved, and the condition of secondary or inflammatory cataract be produced. The iris is not very closely attached at its insertion. Thus, in cases of injury to the eye, it may be torn more or less from its attachments without any damage being done to the other tunics. In one method of making an artificial pupil, known as iridodyalisis, the iris is seized close to its greater circumference by a pair of forceps, and a gap made by forcibly tearing it away from its insertion. In cases of penetrating wounds of the cornea the iris is easily prolapsed. It is so delicate and yielding a membrane, that in performing iridec- tomy the necessary piece of the iris can be seized and pulled out through the corneal incision without offering sensible resistance. The membrane also derives much support from its contact with the lens, for in cases where the lens has been displaced into the vitreous or has been removed by operation, the iris is observed to be tremulous when the globe is moved. Although very vascular, the iris seldom bleeds much when cut, a circumstance that is pro- bably due to the contraction of the muscular fibres that exist so plentifully within it. Sometimes the iris presents a congenital gap in its substance that runs from the pupil downwards and a little inwards. This condition is known as coloboma iridis, and is due to the persistence of the " choroidal cleft." In other cases there can be seen, stretching across the pupil, some shreds of the pupillary membrane. Normally tliis membrane, which is apparent for a few days after birth in some animals, is entirely absorbed before birth. Chap. IV.] The Orbit and Eye. 45 It will now be convenient to take note of the blood and nerve supply of the globe. Blood supply of the eye-ball. — 1. The short ciliary arteries (from the ophthalmic) pierce the sclerotic close to the optic nerve, run some little w^ay in the outer coat of the choroid, and then break up into a capillary plexus that makes up the main part of the inner choroidal coat. In front this plexus gives some vessels to the ciliary processes. The veins from these vessels are disposed in curves as they converge to four or five main trunks (vense vorticosae), which pierce the sclerotic midway between the cornea and the optic nerve. In the choroid they lie external to the arteries. 2. The two long ciliary arteries (from the ophthalmic) pierce the sclerotic to the outer side of the optic nerve, and run forwards, one on either side, until they reach the ciliary region, where they break up into branches that, by anastomosing, form a vascular circle about the periphery of the iris (the circulus major). From this circle some branches pass to the ciliary muscle, while the rest run in the iris in a converging manner towards the pupil, and at the margin of the pupil fonn a second circle (the circulus minor). 3. The anterior ciliary arteries (from the muscular and lachrymal branches of the ophthalmic) pierce the sclerotic (perforating branches) about a line behind the cornea, join the circulus major, and give off branches to the ciliary processes, where they form copious anastomosing loops. These arteries lie in the sub-conjunctival tissue. Their episcleral, or non-per- forating branches, are very small and numerous, and ' are invisible in the normal state of the eye. In inflammation, however, of the ii'is and adjacent parts, these vessels appear as a narrow pink zone of fine vessels round the margin of the cornea, that run 46 Surgical Applied Anatomy, [Chap. iv. nearly parallel to one another, are very closely set, and do not move with the conjunctiva. This zone is known as the zone of ciliary congestion^ or the circum- corneal zone. 4. The vessels of the conjunctiva are derived from the lachrymal and two palpebral arteries. These vessels, in cases of inflammation, are readily dis- tinguished from those last described. They are of comparatively large size, are tortuous, are of a bright brick-red colour, can be easily moved with the con- junctiva, and as easily emptied of their blood by pressure. The differences presented by these two sets of vessels serve in one way to distinguish in- flammation of the conjunctiva from that involving deeper parts. The conjunctival vessels around the margin of the cornea form a closer plexus of anasto- mosing capillary loops, which become, congested in severe superficial inflammation of the cornea, and may then form a zone around the margin of the cornea, which can, however, be distinguished from the " ciliary zone " by the general characters just named. The retina has a vascular system of its own, supplied through the arteria centralis retince, which is nowhere in direct communication with the choroidal vessels, except just at the entrance of the optic nerve. Indeed, the outer layers of the retina which are in relation with the choroid coat are entirely destitute of vessels. Thus, when the central artery of the retina becomes plugged, sudden blindness follows, and as the meagre collateral circulation that is established by the minute anastomoses about the entrance of the nerve is quite insufficient, the retina soon becomes oedema- tous and inflamed. A ])ermanent plugging of the central artery means, therefore, a practical extinction of the vascular system of the retina. In cases of hasmorrhage between the choroid and retina tlie blood must come from the choroidal vessels ; Chap. IV.] The Orbit and Eve. 47 and ill haemorrhage into the vitreous, which often follows injury, the blood may be derived from the retinal vessels, since they run in the inner layers of that membrane, or from the vessels in the ciliary reorion. IVerve supply of the eye-ball. — 1. The ciliary nerves derived from the lenticular ganglion and the nasal nerve pierce the sclerotic close to the optic nerve, and pass forwards between the sclerotic and the choroid, supplying those parts. They enter the ciliary muscle, form a plexus about the periphery of the iris, and then send tibres into the ii'is, which form a fine plexus as far as the pupil. They send branches through the fore part of the sclerotic to the cornea. Thus the eye-ball obtains through these nerves its sensory fibres from the nasal branch of the first di^^ision of the fifth, its motor fibres for the ciliary muscle and sphincter iridis from the third nerve, and many sympathetic fibres, among which are those that supply the dilator muscle of the iris. 2. The conjunctiva is supplied by four nerves : above, the supratrochlear ; on the inner side, the infratrochlear ; on the outer side, the lachry- mal (all branches of the first division of the fifth) ; and below by the palpebral branches of the second division of the fifth. As the ciliary nerves pass forwards between the choroid and the sclerotic, it will be seen that they are readily exposed to injurious pressure against the unyielding sclerotic in cases of increased intraocular tension. The sensation of the globe itself is derived solely from the first division of the fifth. In infiani- matory afiections of the globe, as in corneitis or iiitis, besides the pain actually felt in the eye, there is pain referred along other branches of the first division of the fifth. There is pain over the forehead along the supi'atrochlear, supraorbital, and lachrymal branches (circum-orbital pain), and pain dow^n the side of the 48 Surgical Applied Anatomy. [Chap. iv. nose following the nasal nerve. Or the pain may spread to the second division of the fifth, and discomfort be felt in the temporal region (orbital branch of second division), or be referred to the upper jaw and upper teeth. These affections are associated also with much lachrjmation, the lachrymal gland being also supplied through the first division of the fifth. Photophobia, or intolerance of light, is common in inflammatory afiections of the eye. In this condition there is spasm of the orbicular muscle, keeping the eye closed, or closing it on the least exposure to irritation. Here the nerve most active is the branch of the facial to the orbicularis, and the reflex irritation reaches that nerve either through the branches of the fifth in the cornea and conjunctiva, or through the disturbed optic nerve. Photophobia is most marked in super- ficial affections of the cornea, and is often much benefited by a seton in the temporal region. This acts apparently by counter -irritation of another division (the second) of the fifth nerve supplied to the region of the temple. The relations between the nasal nerve and the orbital contents receive many illustrations in practice. Thus, if the front of the nose be struck, or the skin over its lower part be irritated, as by squeezing a painful boil, profuse lachrymation will frequently be produced. Snuff", too, by stimulating the nasal branch of the ophthalmic nerve, often makes the eyes of the un- initiated to water ; and it is well known that there "are many disturbances about the nose, and the anterior part of the nasal fossae, that can " make the eyes water," Herpes zoster often provides a remarkable illustration of the intimate relation between the nasal nerve and the eye. In this affection, when the regions of the supraorbital and supratrochlear branches of the first division are alone implicated, the eye is usually unaffected ; but when the eruption extends over the Chap. IV.] The Orbit and Eye. 49 part supplied by the nasal nerve, i.e., runs clown the side of the nose, then there is very commonly some inflammation of the eye-ball. In frontal neuralgia watering of the eye (irritation of the lachrymal branch) is very frequently met with. The dangerous area of the eye. — Pene- trating wounds of the cornea alone, or of the sclerotic alone, behind the ciliary region, are by no means serious ; but wounds involving the ciliary body, or its immediate vicinity, are apt to assume the gravest characters. Inflammation in the ciliary region is peculiarly obnoxious, on account of the important vascular and nerve anastomoses that take place in the part. Indeed, as regards blood and nerve supply, there is no more important district in the eye-ball. From the ciliary body also inflammations can spread, more or less, directly to the cornea, iris^ choroid, vitreous, and retina. Plastic, or purulent inflammation of the ciliary body, after injury, is the usual starting point of sympathetic ophthalmia. In this terrible affection destructive inflammation is set up in the sound eye, which is, however, not usually involved until two or three months after the other eye has been injured. " Although at present the exact nature of the process which causes sympathetic inflammation is unknown, and though its path has not been fully traced out, it is certain (1) that the change starts from the region most richly supplied by branches of the ciliary nerves, viz., the ciliary body and iris ; (2) that its first eflfects are generally seen in the same part of the sympathising eye ; (3) that the exciting eye has nearly always been wounded, and in its anterior part ; and that decided l>lastic inflammation of its uveal tract is always present ; (4) that inflammatory changes have in some cases been found in the ciliary nei'ves and optic nerve of the exciting eye. The morbid influence has of late years been generally believed to pass along the ciliary E 5© Surgical Applied Ana tomy. [Chap. iv. nerves, but tlie earlier hypothesis of transmission along the o^tio, nerve has recently been revived, and further, the blood-vessels, lymphatics, and even the blood itself, are, at the present time, claimed by different authors as probable channels " (JSTettleship). The lens measures \ of an inch from side to side, and \ of an inch from before backwards. It, too'ether with its capsule, is in all parts perfectly transparent and perfectly non-vascular. The lens may easily be loosened or displaced by partial rupture of its susj)ensory ligament, and may find its way into the anterior chamber, or, more commonly, back into the vitreous. The lens, if disturbed, may swell, and by the pressure thus exercised cause great damage to the important structures adjacent to it. The capsule is very brittle and elastic, and when torn its edges curl outwards. It has to be lacerated in all cataract opera- tions, and may be ruptured by many forms of violence applied to the eye-ball. When the capsule is wounded the aqueous humour enters, and is imbibed by the lens fibres, which in consequence SM^ell up, and become opaque, thus producing a traumatic cataract. In the various forms of cataract the whole lens, or, more commonly, some portion of it, becomes the seat of opacity. This often commences in the nucleus, and for a long while remains limited to that part ; or it may first involve the cortex, and in such a case the opacity takes the form of a series of streaks that point towards the axis of the lens, and are dependent upon the arrangement of the lens fibres. Of the retina it is only necessary to observe that its connection with the choroid is so slight that it may easily be detached from that membrane by lisemorrhagic, or other effusions, and may indeed be so detached by a simple blow upon the globe. Even when extensively detached it remains, however, as a rule, attached at both the optic disc and the ora Chap. IV.] The Orbit and Eye. 5 1 serrata. The optic nerve as it passes from the brain receives its perineural sheatli from the pia mater, and, in addition, two other sheaths ; an outer from the dura mater, and an inner from the arachnoid. These sheaths remain distinct and separate, and the two spaces enclosed may be injected, the outer from the sub- dural, the inner from the subarachnoid space. Thus inflammatory afi'ections of the cerebral meninges can readily extend along the optic nerve to the optic disc through these spaces in the nerve sheath, while in cases of intracranial disease other than meningeal, the mischief may extend from the brain to the disc along the interstitial connective tissue in the nerve. These connections may serve in part to explain the frequent association of optic neuritis with intracranial disease. The aqueous and I'itreoiis liiinioui'S. — The aqueous fills the space between the capsule and suspensory ligament of the lens and the cornea. The iris divides this space into two parts, the anterior and posterior chambers. Since, however, the iris is largely in actual contact with the lens, it happens that the posterior chamber is represented by a little angular interval between the iris, the ciliary processes, and the zonula of the lens (Fig. 10). The cornea at its circumference breaks up into bundles of fibres, M^hich are partly continued into the front of the iris, and which constitute the ligamentum pectinatum iridis. Between the processes of this ligament there are intervals which lead into certain cavernous spaces called the spaces of Fontana. These spaces in their turn communicate with a lars^e circular canal situate in the sclerotic close to its junction with the cornea, and known as the canal of Schlemm. This space is in communication with the veins of the anterior part of the sclerotic,* and thus through this somewhat * The precise manner in whicli these spaces communicate with the neighbouring veins has not been demonstrated histologically. The statement is founded mainly upon the experiments of Schwalbe. 52 Surgical Applied Ana to my. [Chap. iv. complicated channel the aqueous chamber is brought into relation with the venous circulation. This relation probably explains the ready absorptive powers of the aqueous. Thus, if pus finds its wav into the anterior cham- ber (hypopyon) it is usually readily absorl> ed. The same applies to mode- rate extravasa- tions of blood in the chamber, and the speedy removal of such effusions con- trasts with the difficulty that is experienced in the absorption of blood from the ^dtreous chamber. The Fig. 10. — Section of Globe, showings Iris, Lens Ciliary Region, etc. {Ajier Allen Thomson.) a. Cornea: 6, sclerotic ; c.len.s ; d, iris ; e.ciliarv process ; . . ^ & a, f, conjunctiva; .9,_canal of Scblemm ; h, canal of Petit; treatment 01 SOlt i, anterior marRin of vitreous humour; j, covered by retina ; k, aqueous chamber. choroid cataracts by the " needle opera- tion " depends for its success upon the absorptive powers of the aqueous. In this procedure, the lens capsule having been torn through, and the cataract broken up with needles, the removal of the opaque debris is left to the aqueous, and it is not long before its efficacy in that direction is seen. The vitreous takes little active share in ocular maladies. It may be secondarily affiscted in inflamma- tion of adjacent parts, may be the seat of haemorrhages, Chap. I V.J The Orbit and Eye. 53 and is often occupied by opaque bodies of various kinds. Foreign bodies have lodged in the vitreous for considerable periods without causing any symp- toms. The muscre volitantes that so often trouble the myopic are due to little opaque matters in the vitreous, and very often have exactly the appearance that the corpuscles of the vitreous present when seen under the microscope. The ^dtreous is readily separated from the retina except behind, opposite the disc where the artery to the lens enters in the foetus. Olaiicoiua. is a disease the symptoms of which are all dependent upon an increase in the intraocular tension of the globe. The increased tension is due to an excess of fluid within the eye-ball, and this would appear to be due to certain changes, seldom absent in the glaucomatous, that interfere with the normal escape of this fluid. Normally there is a constant movement of fluid from the vitreous through the suspensory ligament into the posterior chamber, and thence round the pupillary margin of the iris to the anterior chamber. From the anterior chamber the fluid can escaj^e into the veins through the gaps in the liga- mentum pectinatum already alluded to (Fig. 1 0). It is remarkable that in nearly every case of glaucoma these gaps are occluded by the complete obliteration of the angle between the periphery of the iris and the cornea, which angle is normally occupied by the ligamentum pectinatum. The relief given to glaucoma by iri- dectomy appears to depend upon the circumstance that the operation practically opens up again these channels of communication from the aqueous, since the procedure, to be successful, should involve an in- cision so far back on the sclerotic as to fully pass through the angle just alluded to. It is needful also that the iiis should be removed quite up to its at- tachment, and that the portion resected should be 54 Surgical Applied Anatomy. [Chap, i v. considerable. The symptoms of glaucoma are all explained by the effects of the abnormal tension. Thus, the ciliary nerves are compressed against the unyield- ing sclerotic, and give rise to intense j)ain, while the disturbance in their function shows itself in the fixed and dilated pupil and in the anaesthetic cornea. Perhaps the first parts to suffer from compression are the retinal blood-vessels, and the effect upon them will be most obvious at the periphery of the retina, i.e., at the extreme limit of the retinal circulation. Hence follows that gradually narrowing of the visual field which is constant in glaucoma, while the pressure upon the optic nerve produces those flashes of light and other spectra which occur in the disease. The tveahest part of the sclerotic is at the disc at the lamina cribrosa. This part rapidly yields under the pressure, and so produces the "glaucomatous cup." Pressure in the opposite direction pushes the lens forward, and thus narrows the anterior chamber ; while the general interference with the ocular circula- tion is shown in the distended vessels that appear upon the globe. The eyelids. — The skin over the eyelids is ex- tremely thin and delicate, and shows readily through its substance any extravasation of blood that may form beneath it. Its laxity, moreover, renders it very well adapted for certain plastic operations that are performed upon the part. Its loose attachments cause it to be readily influenced by traction, and the shrinking of cicatrices below the lower lid is very aj)t to draw that fold away from the globe, and so produce the condition of eversion of the lid known as ectropion. The contraction of the conjunctiva after inflammatory .conditions, or after it has been subjected to destructive agencies, is prone, on the other hand, to curl either lid inwards towards the globe, and to thus produce entro- pion. The lids present many transverse folds ; one of Chap. IV.] The Orbit and Eye. 55 these on tlie upper lid, deeper and more marked than the rest, divides the lid into two parts, the part below being that that covers the globe, the part above being that in relation with the soft structures of the orbit. In emaciation the lid becomes much sunken in the line of this fold. Incisions should follow the direc- tion of these folds. The lids are very freely sup- plied with blood, and are often the seat of nsevi and other vascular growths. Rodent ulcer so frequently attacks this part that it was origi- nally known as " Jacob's ulcer of the eyelid." The following layers are found in either lid in order : (1) The skin ; (2) the subcutaneous tissue ; (3) the orbicu- laris palpebrarum ; (4) the tarsal cartilasfe and ligament ; (5) the layer of Meibomian glands ; and (6) the conjunctiva. In the upper lid the ^^skln; S. orbicularis; S', its clliary part; loA'Qfny rvi 1 r^al^ vT^ ic! * c, involuntary muscle of eyelid ; d, con- levatOI paipeOlcL is jnnctiva; <-, tarsal cartilage; /, Meibo- fmmrl •n-TQc-ino- fr* +Lo niian erland ; fir, modified sweat gland; lOUna paS:5ing to the ^^ eyelashes ; i, post tarsal glands. tarsal cartilaij^e. The subcutaneous tissue is very lax, and hence the lids swell greatly Avhen cedematous, or when inflamed, and when the seat of heemorrhai^e. * On this Figr. 11,— Vertical Upper Eyelid /7. Section tlirongh (yl/to- Wakleyer.) 56 Surgical Applied Anatomy. [Chap. iv. account it is inadvisable to apply leeches to the lids, on account of the extensive "black eye" that may follow. This tissue is peculiar in containing no fat. At the edge of the lids are found the eyelashes, the orifices of the Meibomian glands, and of some modified sweat and sebaceous glands. This edge, like other points of junction of skin and mucous mem- brane, is apt to be the seat of irritative afiections. Being a free border also^ the circulation is teniiinal, and stagnation in the blood current is not difiicult to produce. Sycosis, an inflammation invohT.ng the hair follicles and some of the glands at the edge of the lid, is among the most common of ophthalmic affec- tions. The common stye also is a suppuration in the connective tissue or in one of the glands at the margin. On everting the lid the Meibomian glands can be seen through the conjunctiva as lines of yellowish granules. The common tarsal cyst is a retention cyst developed in one of these glands. The coojunctiva. — The ocular part of this membrane is thin, very loosely attached, and not very extensively supplied with blood ; the palpebral portion is thicker, more closely adherent, and more vascular. kX the edge of the cornea the conjunctiva becomes continuous with the epithelium covering that tunic. The looseness of the ocular conjunctiva allows it to be freely moved about, and is of great value in some operations : as, for example, in Teale's operation for symblepharon, where a bridge of conjunctiva, dis- sected up from the globe above the cornea, is drawn down over the cornea to cover a raw surface in contact with the lower lid; This lax tissue favours the development of oedema (chemosis), which in extreme cases may reach such a degree that the patient cannot close his eye. The vessels also, being feebly supported, are prone to give way under no great provocation. Thus, subconjunctival haemorrhages may Chap. IV.] The Orbit and Eye. 5 7 occur from severe vomiting, or during a paroxysm of whooping cough. Blood also may find its way beneath the membrane in fractures of the base of the skull. Haimorrhacjes beneath the membrane are unlike other extravasations (bruises), in that they retain tlieir scarlet colour. This is due to the fact that the thinness of the conjunctiva allows oxygen to reach the blood and retain for it an arterial character. Severe inflammation of the conjunctiva may lead to con- siderable cicatricial changes, as is the case in other mucous membranes, and especially, perhaps, in the urethra. The contraction of the conjunctiva after destructive processes is apt to lead to entropion. If both the ocular and the corresponding part of the palpebral conjunctiva have been destroyed, the two raw surfaces left will readily adhere ; the lid will become fused to the globe, and the condition called symblepharon be produced. This condition concerns the lower lid, and is generally brought about by lime or other caustics being accidentally introduced be- tween the under lid and the globe. In one common form of inflammation of this membrane a number of little "granulations" appear upon the palpebral conjunctiva. These are not real granulations, since no true ulceration of the part takes place, but they appear to be made up, some of nodules of adenoid tissue, others of en- larged mucous follicles and of hypertrophied papillae, all of which structures are normally found in the membrane. The condition is known as " granular lids," and is associated with the formation of much new tissue in the deeper parts of the membrane. From the absorption of this new tissue and of these granulations a contracting cicatrix results, leading to much puckering of the membrane, and often to entropion and inversion of the eyelashes. In purulent ophthalmia the cornea is in great risk of 58 Surgical Applied Anatomy. [Chap, i v. destruction, owing to the strangulation of its vessels, and to the effects possibly of the discharge directly upon the membrane. The laclirynial apparatus. — The lachrymal gland is invested by a special fascia which separates it from the general cavity of the orbit ; and, according to Tillaux, this little body can be removed without opening the greater space of the orbit. The gland may inflame, and become so enlarged as to appear as a tumour, which may displace the globe downwards and inwards, and press forwards the oculo-palpebral fold of conjunctiva. If an abscess forms, it most usually breaks through the skin of the upper lid. Cysts of the gland (dacryops) are due to obstruction and distension of some of its ducts. The lachrymal sac is situated at the side of the nose, near the inner canthus, and lies in a groove on the lachrymal and superior maxillary bones. On its outer side, and a little anteriorly, it receives the lachrymal canals. In front of the sac is the tendo oculi. If the two lids be forcibly drawn outwards this tendon can be readily felt and seen, and is the great guide to the sac. It can also be felt as it is tightened, when the lids are firmly closed. It crosses the sac at right angles, and at about the junction of its upper third with its lower two- thirds. A knife entered immediately below the tendon would about open the middle of the sac, and it may be noted that a lachrymal abscess, when about to discharge, always points below the tendon. Epiphora, or overflow of tears, is due in the main to two causes : (1) To an obstruction in any part of the lachrymal passages from the puncta to the opening of the nasal duct in the nose ; (2) to any cause that removes the lower punctum from its contact with the globe, as may be the case in ectropion, in entropion, in swelling of the lower lid, etc. Facial palsy causes epiphora, because, the orbicular muscle being relaxed, Chap, v.] The Ear. 59 the punctum falls away from the globe, and, moreover, the passage of the tears is no longer aided by tlie suction action effected by the muscle in the process of winking. The canaliculi may readily be slit up by a proper knife, and a probe can without difficulty be passed down the nasal duct from the lachrymal sac. The duct is a little over half an inch in length, and the probe that traverses it should pass downwards, and a little backwards and outwards. As affections of the lachrymal sac are often very painful, it may be noted that the nerve supply of tlie sac is derived from the infratrochlear branch of the nasal nerve. CHAPTER V. THE EAR. The pinna and external auditory meatus. — The pinna may be congenitally absent, or may be supplemented by supernumerary portions of the auricle, which may be situated upon the cheek or side of the neck. In the latter situation tliey are sometimes found at the hinder part of a " branchial fistula." (iS'ee page 146.) The pinna may present a con- genita] fistula, which is due to defective closure of the first visceral cleft. This cleft is represented in the normal ear by the Eustachian tube, the tympanum, and the external auditory meatus, the pinna being developed from the integument behind the cleft. In these congenital fistulje, when well marked, the pinna is cleft just in front of the tragus, or through the helix, and there is more or less failure in the closing of the meatus and tympanum, while the membrana tympani will be more or less deficient, or 6o Surgical Applied Anatomy. [Chap. v. entirely absent. In other cases the " fistula " appears merely as a narrow sinus or a depression, running through and from the helix. Accidental removal of the pinna is usually associated with but comparatively little diminution in the acuteness of hearing. The skin covering the auricle is thin and closely adherent. The subcutaneous tissue is scanty, and contains but very little fat. In inflammatory condi- tions of the surface, such as erysipelas, the pinna may become extremely swollen and very great pain be produced from the tenseness of the parts. The pinna and cartilaginous meatus are very firmly attached to the skull, so that the body, if not of great weight, may be lifted from the ground by the ears. In chronic gout, little deposits of urate of soda (called tophi) are often met with in the pinna, and are usually placed in the subcutaneous tissue at the edge of the helix. M. Paul has pointed out that, when ear-rings are worn, the usual hole made by the ring may become converted into a vertical slit, or the ear- ring may cut its way out, leaving a slit in the lobule. This it may do several times if re-applied, thus pro- ducing many slits in the same lobule. He considers such conditions as absolutely diagnostic of scrofula.* The external auditory meatus is about 1|- inches long. It is directed forwards and inwards, having the same direction as the petrous bone. The external meatus, the promontory, the cochlea, and the internal meatus lie nearly in the same line. The canal has a vertical curve about its middle, with the convexity upwards. To straighten the canal for the introduction of specula and other instruments, the pinna should be drawn upwards and a little outwards and backwards. The osseous part forms a little more than one-half of the tube, and is narrower than the * See "Scrofula and its Gland Diseases," by the Author. Lond., 1882. Chap, v.] The Ear. 6i cartilaginous part. The narrowest portion of the meatus is about its middle. The outer orifice is ellip- tical, with its greatest diameter directed from above downwards ; therefore specula should be elliptical in Fig. 12.— Section tlirough the external Meatus, Middle Ear, and Eu-tachian Tube (Tillaus). o, External auditory meatus; J>, tympanum ; c. Eustachian tube; d, internal auditor}- meatus ; e, cochlea ; /, ossicles ; a, membrana tympani ; ft. styloid process. shape rather than round. The inner end of the tube, on the other hand, is slightly wider in the transverse direction. Owing to the obliquity of the membrana tympani, the floor of the meatus- is longer than the roof. The cartilaginous segment of the tube presents many sebaceous glands that may be the seat of minute and very painful abscesses. It also presents numerous 62 Surgical Applied Ana to my. [Chap. v. ceruminous glands, wliich secrete the cerumen of the ear, and which, when their secretion is excessive, may produce the plugs of wax that often block the meatus. There are neither hairs nor glands in the lining of the bony part of the tube. The skin of the meatus, when inflamed, may pro- duce an extensive muco - j)urulent discharge — otitis externa. Polypi are apt to grow from the soft parts of the canal, and exostoses from its bony wall. Foreign bodies are frequently lodged in the meatus, and often involve great difficulties in their extraction. It would appear that in many cases more damage is done by the surgeon than by the intruding substance. Mason reports three cases where a piece of slate-pencil, a cherry-stone, and a piece of cedar-wood were lodged in the canal for respectively forty years, sixty years, and thirty years. The up'per wall of the meatus is in relation with the cranial cavity, from which it is only separated by a thin layer of bone. Thus, abscess or bone disease in this part may readily lead to menin- gitis. A case is reported where an inflammation of the cerebral membrane followed upon the retention of a bean within the meatus. The anterior wall of the canal is in relation with the temporo-maxillary joint and with part of the parotid gland. This may serve in one way to explain the pain often felt in moving the jaw when the meatus is inflamed, although, at the same time, it must be remembered that movement of the lower maxilla produces a movement in the carti- laginous meatus, and that both the canal and the joint are supplied by the same nerve (the auriculo-temporal). From its relation to the condyle of the jaw, it follows that this wall of the meatus has been fractured by that condyle in falls upon the chin. Tillaux states that abscess in the parotid gland may spread into the meatus through the anterior wall of the passage. Chap, v.] The Ear, 63 The posterior wall separates the meatus from the mastoid cells, and through this partition inflammation may extend from one part to the othei-, especially as the cartilage of the tube is deficient at its upper and posterior parts. The inferior wall of the bony meatus is very dense and substantial, and corresponds to the vaginal and styloid processes. Blood supply. — The pinna and external meatus are well supplied with blood by the temporal and ])Osterior auricular arteries^ the meatus receiving also a branch from the internal maxillary. In spite of this supply, the pinna is frequently the seat of gangrene from frost-bite. This is due to the fact that all the vessels are superficial and are close beneath the surface, that the part is much exposed to cold, and that the pinna lacks the protection of a covering of fat. The same conditions predispose to gangrene of the nose from external cold. Bloody tumours (hsematomata) are often met with on the pinna, and are said to be more common in lunatics. They appear to be frequently due to injury, and consist of an extravasation between the perichondrium and the cartilage. Nerve supply. — The outer surface of the pinna is supplied by the auriculo-temporal nerve, with the exception of the skin over the antitragus, the vertical part of the antihelix, the corresponding part of the helix and its fossa, and the lobule, which parts are all supplied by the great auricular nerve. The inner surface is almost entirely supplied by the latter nerve, the small occipital nerve giving a branch to the upper extremity, and Arnold's nerve a branch to the back of the concha, near the mastoid process. The meatus is supplied mainly by the auriculo-temporal, with, in addition, a contribution from Arnold's nerve, which goes to the lower and back part of the canal, not far from its commencement. Arnold's nerve, a 64 Surgical Applied Anatomy. [Chap. v. little branch from the pneumo - gastric, has been credited with a good deal in connection with the nerve relations of the ear. After a heavy dinner, when the rose-water comes round, it is common to see the more experienced of the diners touch the lower part of the back of the ear with the moistened serviette. This is said to be very refreshing, and is supposed to prove to be an unconscious stimulation of Arnold's nerve, a nerve whose main trunk goes to the stomach. Hence, this little branch has been facetiously termed "the alderman's nerve." Ear cougliiug:, ear sneezing^, ear ya\i^nmg^. — It is not uncommon to have a troublesome dry cough associated with some mischief in the meatus. Sometimes the mere introduction of a speculum will make the patient cough. A case is reported, where a troublesome cough persisted for eighteen months, and at once ceased on the removal of a plug of wax from the ear. In such cases, the irritation is pro- bably conveyed to the trunk of the vagus by Arnold's nerve, and is then referred to the respiratory tracts which are so extensively supplied by that trunk. By means of this little branch the ear is brought into very direct connection with the great nerve of the lung. Dr. Woakes has carefully investigated the matter of ear-sneezing, a iwopos of a case where troublesome sneezing was set up by a plug of wax in the meatus. He considers that the irritation in this case also is conveyed to the respii'atory organs by Arnold's nerve. The relation of this small nerve to the nerve of the stomach is illustrated by a case cited by Arnold, where severe chronic vomiting was at once cured by extracting from each ear of a child a bean that had been introduced in play. In the repeated yawning that is sometimes set up by ear ailments, the irritation is no doubt conveyed from the meatus by the auriculo- temporal nerve. Chap, v.] The Ear, 65 This nerve is a branch of the third division of the fifth, and it is from this same division that the branches come oft' that supply the muscles of the jaw. The inferior dental nerve, that goes to the lower teeth, is a branch of the same division, as is also the gustatory nerve ; and the somewhat direct connection of these nerves with the ear may explain the frequent association of ear-ache and tooth-ache, and the fact that disease in the anterior part of the tongue (gustatory nerve) is often attended by pain in the ear. It is a common practice to introduce ear-rings, with the idea of relieving obstinate aftections of the eye. How such a treatment can act, if it acts at all, is hard to understand. It is true that the main nerve-supply of the eye and of the conjunctiva comes from the fifth nerve, but, unfortunately for any nerve theory, the lobule of the ear is only supplied by the great auricular nerve. If the ear-ring, in such cases, were introduced through the upper part of the ear, supplied as it is in front by the fifth nerve, some connection might be traced. Hilton reports a case of obscure pain in the ear which was found to be due to an enlarged gland in the neck, that pressed upon the trunk of the great auri- cular nerve. JTIeiiibrana tynipaiii. — This membrane is very obliquely placed, forming with the horizon an angle of 45°. At birth it is much more nearly horizontal, the angle being one of only 10*^. In cretins, and in some idiots, it is said to retain this inclination through life. Owing to the sloping downwards of the bony wall of the meatus at its inner end, that wall forms with the lower edge of the membrana a kind of sinus in which small foreign bodies may readily lodge (Fig. 12). The ring of bone to which the membrane is attached is deficient at its upper and anterior part. F 66 Surgical Applied Anatomy. [Chap. v. The gap so formed is called the notch of Rivini, and is occupied by loose connective tissue, covered by a con- tinuation of the lining of the meatus, and through it pus may escape from the middle ear into the auditory canal without perforating the membrane. When the mem- brane gives way owing to a violent concussion trans- mitted through the air, it often gives way opposite the notch, its attachments here being obviously less secure than elsewhere. The membrane possesses but little elasticity, as shown by the very slight gaping of the part after it has been wounded. It is for this reason, among others, that perforations made in the membrane by the surgeon heal so very rapidly. The membrane has been ruptured during fits of sneezing, coughing, vomiting, etc. The same lesion has followed a box on the ear, and even simple concussion such as that pro- duced by a loud report. The umbilicus, or deepest point of the depression in the diaphragm, is just below the centre of the entire membrane, and corresponds to the attachment of the end of the handle of the malleus. The rest of the handle can be seen througrh the membrane during life. The head of the malleus is in no connection with the membrane, being above its highest limits. The seg- ment of the membrane above the umbilicus is very freely supplied by vessels and nerves ; it corresponds to the handle of the malleus, and to the chain of ossicles, and is opposite to the promontory and the two fenestrse. The chorda tympani nerve also runs across this supra-umbilical portion. . The segment below the umbilicus, on the other hand, corresponds to no very important parts, and is less vascular and less sensitive. Paracentesis of the tympanum through the membrana tympani should therefore always be performed in the sub-umbilical segment. The membrane is supplied by the stylo-mastoid artery, and the tympanic branch of the internal max- Chap, v.] The Ear. 67 illary, and obtains its nerve-supply from the auriculo- temporal. The tympanum.— The width of the tympanic ca^^.ty, as measured from its inner to its outer wall, varies from yVth to ^th of an inch. The narrowest part is that between the umbilicus of the membrana and the promontory. A fine rod thrust through the centre of the membrana tympani would hit the pro- montory on the mner wall of the cavity. Above the promontory is the fenestra oval is, and below and behind it the fenestra rotunda. Skirting the upper and posterior margin of the inner wall of the tympa- num is the aqueduct of Fallopius, containing the facial nerve. The wall of the aqueduct is so thin that inflammatory mischief can readily extend from the middle ear to the facial nerve. The upper wall is very thin, and but little bone separates it from the cranial cavity. The suture between the squamous and petrous bones is found in this wall, and by means of the sutural membrane that separates the bones in the young inflammatory changes may readily spread from the tympanum to the meninges. Tlie //oor is very narrow. Its lowest part is below the level of both the membrana tympani and the orifice of the Eusta- chian tube, and hence pus may readily collect in this locality. It is separated by a thin piece of bone from the internal jugular vein behind, and from the internal carotid artery in front. Fatal haemorrhage from the latter vessel has occuiTed in connection with destruc- tive changes in this part of the ear. The posterior wall presents the openings of the mastoid cells. These cells are often the seat of suppurative collec- tions, and may be opened by a proper trephine applied to the surface of the mastoid process about half an inch behind the ear. These cellular spaces in the bone are in close relation with the lateral sinus, and thus it happens that thrombosis of the sinus has 68 Surgical Applied Anatomy. [Chap. v. sometimes occurred in connection witli mischief in the cells. The mastoid cavities, like the tympanum, con- tain air, and in cases where the outer surface of the bone has been spontaneously perforated, a tumour has appeared on the skull that contained air, and that could be increased in size by forcing air into the ear through the Eustachian tube. Such tumours are known as pneuviatoceles, and the process that leads originally to the perforation of the bone is of obscure nature. In some cases it seems to have been simply atrophic, and in other instances to have been due to " caries sicca." On the anterior wall of the tympanum is the open- ing of the Eustacliiaii tube. This tube is one and a half inches long, and by opening into the pharynx serves to keep a proper supply of air in the tym- panum, and so equalise the pressure upon the two sides of the membrane. The pharyngeal orifice of the tube is usually shut. During swallowing, however, it is opened, by the action probably of the tensor palati muscle. If the nose and mouth be closed, and the cheeks blown out, a sense of pressure is produced in both ears. The hearing, at the same time, is dulled, and the change is due to the bulging out of the mem- brana tympani by the air thus forced into the tym- panum. This method of inflating the middle ear is known as Valsalva's method. In " Politzer's method " of passing air into the Eustachian tube, the patient's mouth is closed, while into one nostril the nozzle of a caoutchouc bag filled with air is introduced, and the nostrils then held firmly closed. The patient is asked to swallow a mouthful of water, while at the same moment the bag is forcibly emptied, and the air, having no other means for escape, is thus driven into the open Eustachian tube. The surgeon listens for the little noise caused by the entrance of the air by means of a tube that Chap, v.] T}iE Ear. 69 passes between the patient's meatus and his own. Pro- longed closure of the Eustachian tube leads to deaf- ness, and thus impairment of hearing may follow upon great thickening of the mucous membrane of the tube due to the extension of inflammatory mischief from the pharynx. In the deafness associated with enlarged tonsils, the hypertrophic change extends to the mucous lining of the tube, and in the cases of many pharyngeal gi'owths and nasal polypi, the orifice of the tube is mechanically obstructed. The near relation of the pharyngeal end of the tube to the posterior nares serves to explain a case w^here suppuration in the mas- toid cells followed upon plugging of the nares for epistaxis. A probe passed up the Eustachian tube from the pharynx w^ould hit the joint between the incus and the stapes, and would then enter the mastoid cells (Tillaux). The upper edge of the pharyngeal orifice of the tube is about half an inch below the basilar process, half an inch in front of the posterior wall of the pharynx, half an inch behind the posterior end of the inferior turbinated bone, and half an inch above the soft palate (Tillaux). Just behind the elevation formed at the orifice of the Eustachian tube, there is a depression in the wall of the pharynx, known as the fossa of Rosenmiiller. It may be mistaken for the orifice of the tube, and may readily engage the point of an Eustachian catheter. To pass the Eustachian catheter, the in- strument is carried along the floor of the nares wdth its concavity downwards, "until its point can be felt to drop over the posterior edge of the hard palate into the pharynx. The instrument should now be w^thdraAvn until its point can be felt to rise again on the posterior edge of the hard palate; having arrived at this pomt, the catheter should be pushed onwards about one inch, and during its passage its point should 70 Surgical Applied Anatomy. [Chap. vi. be rotated outwards througli a quarter of a cii-cle."* This nianoeu\'Te should engage it on the orifice of the tube. Blood supply. — The tympanum is supplied by the following arteries, the tympanic of the internal maxillary and internal carotid, the petrosal of the middle meningeal, and the stylo-mastoid of the pos- terior auricular. It is the distribution of the main trunk of the last-named vessel that gives some reason for the practice of applying blisters behind the ear in disease located in the deeper parts. The fact that some of the tympanic veins end in the superior petrosal and lateral sinuses, gives another explanation of the frequent occurrence of thromboses of those channels in inflammatory affections of the middle ear. The chorda tympani nerve, from its exposed position in the tympanum^ is very likely to be damaged in suppurative disease of the middle ear ; and Urban- tschitsch has stated that such disease in this part may be associated with anomalies of taste. CHAPTER VI. THE NOSE AND NASAL CAVITIES. 1. The nose. — The shin over the root, and the greater part of the dorsum, of the nose, is thin and lax. Over the alse, however, it is thick, very adherent to the deeper parts, and plentifully su])plied with sebaceous and sweat glands. Inflammation of the integuments over the cartilaginous portion of the nose is apt to be very painful, and to be associated A\'ith much vascular engorgement. The pain depends * Smith and Walsham's " Operative Surgery," p. 12. 2ud ed 1876. Chap. VI.] Nose and Nasal Cavities, 71 upon the tenseness of the part, which prevents it from swelling without producing much pressure upon the nerves, while the engorgement depends upon the free blood-supply of the region, and the fact that the edge of the nostril being a free border, the circulation there is terminal, and apt therefore to favour congestion. The great number of sebaceous glands about the lower part of the nose renders it a favourite spot for acne. It is here that the form of acne termed acne hypertrophica is met with ; a condition that produces the appearance known as " grog-blossoms." The nose, too, is frequently attacked by lupUs, and it is indeed over the dorsum of the nose that lupus erythematosus is most commonly met with. Kodent ulcer also is apt to appear in this region, especially in the fold between the ala of the nose and the cheek. The integument of the nose is very well supplied with blood, and for this reason the part is well suited for the many plastic operations that are performed upon it. Wounds in this region heal kindly, and even the extensive wound made along the line between the nose and the cheek in removal of the upper jaw leaves very little deformity. In many reported cases portions of the nose have been entirely severed, and have united to the face on being immediately re-applied. In spite of its full blood-supply, the nose, for reasons already given when speaking of the j)inna (page 63), is prone to gangrene fi-om exposure to severe cold. A specimen in the museum of the Royal College of Surgeons illustrates a remarkable form of gangrene of the nose. The specimen is the larynx of a man who cut his throat, and lost a great quantity of blood. Before he died his nose sloughed. The skin over the root of the nose is supplied by the nasal branch of the first division of the hfth ; as is also the skin over the alie and in the region of the nostril. The middle or greater part of the side of the 72 Surgical Applied Anatomy. [Chap. vi. nose is supplied by tlie second division of the fifth, and is the seat of pain in neuralgia of that trunk. The fact that the nasal nerve is a branch of the ophthalmic trunk, and has intimate connections with the eye, serves to explain the lachrymation that often follows painful affections about the nostril, as, for example, when the edge of the nostril is pinched (page 48). The cartilaginous part of the nose is often destroyed by lupus, by syphilitic ulceration, and other destructive affections. The parts so lost have been replaced by the various methods included under the head of rhinoplasty. It is well to bear in mind the limits of the cartilaginous segment of the nose, and to remember that in introducing a dilating speculum the instrument should not be passed beyond those limits.. In the subjects of inherited syphilis the bridge of the nose is often found to be greatly depressed. This depends upon no actual loss of parts^ but rather upon imperfect development from local mal-nutrition, that mal-nutrition following upon a severe catarrh of the mucous membrane. The deformity only occurs, therefore, in those who have had "snuffles" in infancy. The nasal bones are often broken by direct violence. The fracture is most common through the lower third of the bones, where they are thinnest and least supported. It is rarest in the upper third, where the bones are thick and firmly held, and where, indeed, considerable force is required to produce a fracture. Since no muscles act upon the ossa nasi, any displacement that occurs is due solely to the direction of the force. Union takes place after these fractures with greater rapidity than perhaps obtains after fracture of any other bone in the body. In one case noted by Hamilton, " the fragments were quite firmly united on the seventh day." If the mucous membrane of the nose be torn, these fractures are apt Chap. VI.] Nose and Nasal Cavities. 73 to be associated with emphysema of the subcutaneous tissue, which is greatly increased on blowing the nose. The air in such cases is derived, of course, from the nasal fossae. In fractures of the upper third of the ossa nasi the cribriform plate may be broken, but it is ques- tionable whether this complication can occur when the fracture is limited to the lower third of the bones. The root of tlie nose is a favourite place for meningoceles and encephaloceles, the protrusion escaping through the suture between the nasal and frontal bones. Such protrusions, when occurring in this place, are often covered by a thin and vascular integument, and have been mistaken for njevoid growths. 2. The nasal cavities.— The anterior nares have somewhat the shape of the heart on a playing- card, and the aperture as a whole measures about 1;^ inches vertically, and a little less than 1\ inches transversely, at its widest part. The plane of the nostril is a little below that of the floor of the nares. To examine the nasal cavities, therefore, the head should be thrown back, and the nose drawn upwards. The anterior nares can be well explored by the finger introduced into the nostril, and the nasal aj^ertures are just so wide on each side of the septum as to allow the finger to be passed far enough back to reach another finger introduced into the posterior nares through the mouth. An efl'ectual way of removing soft polypi in the adult is by tearing them away by the two fingers so introduced. The operation is a little rough. By the most gentle introduction of the finger into the nostril it is often possible to feel the end of the inferior turbinated bone. The anterior nares, and front of the nasal cavities, can be well explored by Rouge's operation. In this procedure the upper lip is everted, and a transverse cut made through the mucous membrane into the soft parts that connect the upper lip with the upper jaw. The incision extends 74' Surgical Applied Anatomy. [Chap. vi. between the second bicuspid teeth of either side. The soft parts connecting the upper lip and nose to the bone are divided without damaging the skin, and the flap is dissected up until the nares are sufficiently exposed. The posterior nares. — If a little miiTor, somewhat similar to that used in laryngoscopy, be cautiously introduced behind the soft palate through the mouth, and illumined from the mouth, the following parts may, under favourable circumstances, be seen : the posterior nares, the septum, the middle and inferior turbinated bones, the Eustachian tube, and the mucous membrane of the upper part of the pharynx. This mode of examination is very difficult to carry out, and is known as posterior rhinoscopy. The parts just named can all be felt by the finger introduced behind the soft palate through the mouth. The posterior nares are often plugged to arrest severe bleeding from the nose, and in order to cut a proper sized plug it is desirable to bear in mind the dimen- sions of the apertures. Each aperture is of regular shape, and measures about half an inch transversely by one and a quarter inches in the vertical dii'ection in a well-developed adult skull. As regards the nasal cavities generally, it is well to note that the floor is wider at the centre than at either end, that the vertical diameter is greater than the transverse, and is greatest also about the centre of the fossae. Forceps introduced into the nose, therefore, are most conveniently opened if opened verticall}^ From a reference to the relations of the nasal fossae, it will be understood that inflammation of the lining membrane (coryza) may extend to the pharynx via the posterior nares ; may extend up the Eusta- chia7i tube and cause some deafness; may reach the Chap. VI.] Nose and Nasal Cavities. 75 lachrymal sac and conjunctiva through the nasal duct ; and may extend to the frontal sinuses and the antrum, producing frontal headache and cheekache. These relationships are often demonstrated in a severe " cold in the head." From the nearness of the nasal fossre to the cranial cavity it happens that meningitis has followed upon purulent inflammations of the nose. Foreifjn bodies of various kind are often lodsjed in the nose, and may remain there for some years. Thus Tillaux reports the case of an old woman aged 64, from whose nose he removed a cherry stone that had been there for twenty years. In washing out the nasal cavities with the " nasal douche'' the fluid is introduced by means of a syphon. The nozzle of the syphon tube is introduced into one nostril, the mouth is kept open, and the fluid runs through that nostril, passes over the soft palate, and escapes from the other nostril. The latter cavity is therefore washed out from behind forwards. The course of the fluid depends upon the fact, that when the mouth is kept open, there is such a dis- position to breath through it alone, that the soft l)alate is drawn up and the nares cut otF from the pharynx. The roof of each nasal fossa is very narrow, being only about \ of an inch in width. It is mainly formed by the thin cribriform plate, but its width is such that the danger of the roof being penetrated by so large a substance as a pair of polyp forceps has been greatly exaggerated. The cranial caAT.ty has, however, been opened up through the roof of the nose by penetrating bodies introduced both by accident and with homicidal intent. Fracture of this part also has been associated with very copious escape of cerebro-spinal fluid through the nostrils. A meningocele may protrude through the nasal roof. In a case reported by Lichtenberg, the mass hung from the mouth, having passed through 76 Surgical Applied Anatomy. [Chap. vi. a congenital fissure in the palate. It was mistaken for a polyp, was ligatured, and death rasulted from intracranial inflammation. The septum is seldom quite straight. The devia- tion may be congenital, or may follow an injury. It has been pointed out that a deviation of the septum may seriously interfere with the singing voice. The nose also is seldom quite straight, and French authors ascribe this to some deviation of the septum, often de- pendent upon the practice of always blowing the nose with the same hand. If the deviation of the septum be considerable, it may more or less block one nostril, and, until the opposite nostril is examined, be mis- taken for a septal tumour encroaching upon the cavity. The flattened nose in acquired syphilis is usually due to destruction of the septum, and more or less implica- tion of the adjacent bones. Workmen exposed to the vapour of bichromate of potash are liable to a peculiar perforation of the septum known as " bichromate disease." Outer Ti'^all. — The inferior turbinated bone may interfere with the introduction of a Eustachian catheter if the curve of the instrument be too great. The anterior end of the bone is about f of an inch behind the orifice of the nostril. The opening of the nasal duct is about one inch behind the orifice of the nostril, and about f of an inch above the nasal floor. The height of the inferior meatus is about ^ of an inch. Tlie middle meatus is widely open in front, and unless care be taken to keep the point of any instrument well towards the floor of the fossa, it is easier to pass the instrument into the middle than into the inferior meatus. The opening into the antrum is about the centre of the middle meatus, and is nearly one inch above the floor of the nasal fossae. The middle tur- binated bone is high up. Its highest point — its an- terior extremity — is nearly on a level with the teudo Chap. VI.] Nose and Nasal Cavities. 77 oculi. At the front part of the middle meatus the infundibulum opens. Rhinolithes (stone-like masses of calcareous matter, formed, as a rule, around foreign substances) are most often found in the inferior meatus. The width of the nasal floor is about half an inch, or a little over. Its smooth surface greatly favours the passage of instruments. The mucous membrane lining the nasal cavi- ties varies in parts. It is very thick and vascular over the turbinate bones and over the septum, while over the nasal floor, and in the intervals between the turbinate bones, it is very m\ich thinner. The mucous membrane lining the various sinuses and the antrum is conspicuously thin and pale. The membrane is pro- vided with many glands, which are most conspicuous over the lower and hinder parts of the outer wall, and over the posterior and inferior parts of the septum. These glands may be the subject of considerable hyper- trophy. They are capable of providing also a very copious "watery secretion, which has, in some cases of chronic coryza following injury, been so free as to be mistaken for an escape of cerebro-spinal fluid. There is also much adenoid, or lymphoid, tissue in the nasal mucous membrane, which is the primary seat of the chief scrofulous affections that invade this part. Over the inferior turbinated bone the mucous membrane is very thick, lax, and vascular, and when the seat of chronic inflammation, it may present itself as a large movable fold that has often been mistaken for a polyp. From the comparatively lax attachment of the mucous membrane of the septum to the parts beneath, it happens that h?ematomata (localised extravasations of blood) are often met with beneath the septal mucous membrane after a blow on the nose. Polypi are often met with in the nose. They are of two kinds^ the mucous or myxomatous polyp 7 8 Surgical Applied Anatomy. [Chap. vi. that springs usually from the mucous membrane over the middle or inferior turbinate bones, and the fibrous or sarcomatous polyp that usually takes origin from the periosteum of the nasal roof, or from that of the base of the skull. Polypi of the latter kind spread in every available direction. They expand the bridge of the nose, close the nasal duct and cause epiphora, depress the hard palate and encroach upon the mouth, invade the antrum and expand the cheek, grow down into the pharynx, pushing forwards the velum palati, and may penetrate even through the inner wall of the orbit. In one remarkable case quoted in the Lancet for 1877, a tumour springing from the sheath of the suj)erior maxillary nerve just after its exit from the foramen rotundum, projected into the nasal fossae. It was mistaken for a polyp, and attempts to remove it led to meningitis and death. The blood supply of the nasal cavity is exten- sive, and is derived from the internal maxillary, ophthalmic, and facial arteries. With regard to the veins, it may be noted that the ethmoidal veins that come from the nose enter the ophthalmic vein, while in children a constant communication exists between the nasal veins and the superior longitudinal sinus through the foramen caecum. This communication may also be maintained in the adult. These connec- tions may, in part, serve to explain the occurrence of intracranial mischief as a consequence of certain in- flammatory affections of the nasal cavities. Bleeding from the nose, or epistaxis^ is a common, and often a serious circumstance. Its frequency is to a great ex- tent due to the vascularity of the mucous membrane, to its laxity, and to the fact that the veins, especially those over the lowest turbinate bone, form extensive plexuses, and produce a kind of cavernous tissue. The epistaxis is often due, therefore, to interference with the venous circulation, as seen in cases of cervical Chap. VI.] A'^OSE AND N'aSAL C A VI TIES. 79 tumour pressing upon the great veins^ in the paroxysms of whooping cough, and the like. The beneficial effect of raising the arms in epistaxis is supposed to depend upon the extra expansion of the thorax thus produced, and the aspiratory effect thus brought to bear upon the cervical veins. The bleeding may be copious and long continued. Thus Spencer Watson reports a case where the epistaxis continued on and off for twenty months without obvious cause. Martineau mentions an instance in which 12 lbs. of blood were lost in sixty hours, and Fraenkel records a case where 75 lbs. of blood are said to have escaped from first to last. In several instances the hemorrhage has proved fatal. The seat of the bleeding is often not easy to detect, even when the examination is post mortem. The nerve supply of these parts is derived from the olfactory nerve, and from the first and second divisions of the fifth nerve. The lachrymation that often follows the introduction of irritants into the front of the nares, may be explained by the fact that that part of the cavity is supplied freely by the nasal nerve, a branch of the ophthalmic trunk. As an ex- ample of transference of nerve force in the opposite direction, may be noted cases where a strong sunlight falling upon the eyes has produced an attack of sneezing. The olfactory nerves are situated high up in the cavity, and thus, in smelling intently, the individual sniffs deeply and dilates the nostril. The inability to dilate the nostril in facial paralysis, may explain the partial loss of smell sometimes noted in such cases. It is said (Althaus) that anosmosia, or loss of the sense of smell, when following upon an injury to the head, may be due to a rupture of the olfactory nerve-fibres, as they pass through the cribriform foramina. Surgery affords some examples of the possible violence of the act of sneezing. Thus a man sneezed vigorously when his hand was firmly supported upon an object, and 8o Surgical Applied Anatomy. [Chap. vi. produced a subcoracoid dislocation of his shoulder {Lancet, 1878). In another case, the ninth rib on the left side was fractured during a fit of sneezing {Med. Times, 1862). Mr. Pitts (Lancet, 1883) has, how- ever, reported the strangest case of all, a case in which all the coverings of a large femoral hernia were rup- tured during the act of sneezing, so that the bowels escaped. Some of the lympliatics of the nasal fossse enter certain glands placed behind the pharynx, in front of the rectus capitis anticus major. Hence, as Fraenkel has pointed out, " retro-pharyngeal abscess may arise in consequence of diseases of the nose." Other lympha- tics go to the submaxillary and parotid lymph glands, and it is common to find the former set of glands en- larged in nose aftections, especially in the scrofulous. The siiiuses. — These may be briefly dealt with. The, fi'ontal sinuses are not present in early youth, but develop as age advances. They are practically formed from the diploe. Large frontal sinuses do not neces- sarily imply large external prominences over the glabella and superciliary eminences. They often de- velop more as the brain shrinks, and appear then to follow, as it were, the receding brain. Bony tumours often grow from the interior of these sinuses, and are known as enostoses. It is obvious that a depressed fracture may exist over a frontal sinus, without the cranial cavity being damaged. In such cases, the in- spissated contents of the sinus have been mistaken for brain matter escaping. Since the sinuses commu- nicate with the nose, much emphysema may follow upon fracture of the sinus wall. Insects have found their way into these cavities. " Centipedes are par- ticularly liable to be found in the frontal sinuses, where they may remain for years, the secretions of these cavities furnishing them with sufficient nourish- ment " (Fraenkel). Larvae have also been found here, Chap. VI.] Nose and Nasal Cavities. 8i and maggots that have developed within the nose have managed to make their way to the frontal sinuses. A case is reported where epistaxis, extend- ing over many years, was due to an insect (the pen- tastoma tsenioides) that had settled in these sinuses. One day it was sneezed out, and no further bleeding occurred (Med. Times, 1876). The last-named para- site is said to be often met with in the frontal sinus of the dog. The antrum exists at birth, but attains its largest dimensions in old age. Tumours of various kinds are apt to develop in this cavity, and to distend its walls in various directions. Thus the growth breaks through the thin inner wall and invades the nose, it pushes up the roof of the cavity and invades the orbit, it encroaches upon the mouth through the lloor of the antrum, and makes its way also through the somewhat slender anterior wall into the cheek. The densest part of the antrum wall is that in relation to the malar bone, and this part does not yield. There is little inducement for any growth to spread back- wards, although it sometimes invades the zygomatic and pterygo- maxillary fossse. As the infraorbital nerve runs along the roof of the antrum, while the nerves of the upper teeth are connected with its walls, these structures are pressed upon in growths springing from the antrum, and much neuralgia of the face and teeth often produced. In tapping the antrum, a spot is usually selected just above the second bicuspid tooth, since the bone is here thin and is conveniently reached. In some cases it is suffi- cient to extract a molar tooth, since the fangs of these teeth often enter the cavity of the antrum. The teeth usually selected are either the first or the third molar. As the result of a fall, one of the upper teeth has been entirely driven into the antrum and lost to view. In one case, reported by Haynes "Walton, an upper G S2 Surgical Applied Anatomy. [Chap. vii. incisor was found lying loose in the antrum three and a half years after the accident that had driven it there. CHAPTER YII. THE FACE. The parts of the face, other than those already dealt with, will be considered under the following heads: (1) The face generally; (2) the parotid region ; and (3) the upper and lower jaws and parts connected with them. The lips will be considered with the "cavity of the mouth" (chap. viii.). 1. The face generally.— The skin of the face is thin and fine, and is more or less intimately adhe- rent by a delicate subcutaneous tissue to the parts beneath. The skin generally is very freely supplied v/ith sebaceous and sudoriparous glands, and hence the face is very commonly the seat of acne, an erup- tion that specially involves the sebaceous follicles. It hajDpens from the thinness of the skin, and from the absence of dense fasciae, that facial abscesses usually soon point and seldom attain large size. The cellular tissue of the face is lax, and readily lends itself to sjDreading infiltrations, so that in certain inflammatory affections the cheeks and other parts of the face may become greatly swollen. In general dropsy, also, the face soon becomes "jDufFy," the change first appearing, as a rule, in the lax tissue of the lower lid. The skin over the chin is peculiarly dense and adherent to the parts beneath, and in most respects closely resembles the integument of the scalp. When such parts of the integuments of the face as cover prominent bones, such as the parts over the Chap. VII.] The Face. 83 malar bone, the chin, the upper lid, are struck by a blunt instrument or in a fall, the wound produced has often the appearance of a clean incised wound, just as obtains in contused wounds of the scalp. The mobility of the facial tissues renders this part very suitable for the performance of plastic operations of various kinds, and their vascularity generally insures a ready and sound healing. Al- though there is a large quantity of fat in the subcu- taneous tissue in this region, yet fatty tumours are singularly rare upon the face. They appear, indeed, to avoid this region. Thus M. Denay reports the case of a man who had no less than 215 fatty tumours over different parts of his body, but not one upon his face. The thickness of the tissues of the cheek and lips favour the embedding of foreign substances in those parts. Thus, a tooth that has been knocked out has remained for some time embedded in the lip. Henry Smith reports a remarkable case, where he removed a piece of tobacco-pipe three inches long from the cheek, in the tissues of which it had been era- bedded for several years. The soft tissues of the cheek greatly favour the spread of destructive pro- cesses. Thus in cancrum oris, a form of gangrene of the face attacking the young, the whole cheek may be lost in a few days. Great contraction is apt to follow upon loss of substance in the cheek, so that in some cases the jaws may be firmly closed, as is seen after recovery from advanced cancrum oris. The face is peculiarly liable to be the seat of certain ulcers, espe- cially the rodent and lupoid ulcer, and is the part most often attacked by " malignant pustule," a disease transmitted to man from cattle afflicted with a malady known in this covmtry as " murrain," and in France as ** charbon." Blood supply. — The tissues of the face are very vascular, and are liberally supplied with blood-vessels in 84 Surgical Apt lied Anatomy. [Chap. vii. all parts. The finer vessels of the skin often appear per- manently injected or varicose in the drunken, or in those who are exposed to cold, or are the subjects of certain forms of acne. Thus, nsevi, and the various forms of erectile tumour, are common about the face. For a like reason also wounds of the face, while they may bleed readily when inflicted, are apt to heal with singular promptness and accuracy. All wounds, therefore, of this part should have their edges care- fully adjusted as soon after the accident as possible. Extensive flaps of skin that have been torn up in lacerated wounds often retain their vitality in almost as marked a manner as do like flaps torn up from the scalp. Extensive injuries of the face associated with great loss of substance are often repaired in a most remarkable manner, as has been illustrated in gunshot wounds, where a considerable portion of the face and upper jaws has been blown away. The low mortality after severe injuries to the face is due, however, not only to the excellent powers of repair the part pos- sesses, but also to the fact that the face contains no organs essential to life, that its bones are soft and thin and do not favour extensive splitting, and that there are several passages and cavities in the region through which discharges may escape. One of the most terrible instances of injury not immediately fatal is reported by Longmore : '' An oflicer of Zouaves, wounded in the Crimea, had his whole face and lower jaw carried away by a ball, the eyes and tongue in- cluded, so that there remained only the cranium, sup- ported by the neck and spine." He lived twenty hours. The pulsations of the facial artery can be best felt at the lower border of the jaw, where the vessel crosses just in front of the anterior border of the masseter muscle. It is here covered only by the integu- ment and platysma, and can be readily compressed Chap. VII.] The Face. 85 against the bone, or ligatured. The anastomoses of the artery upon the face are so free, that, when the vessel is divided, both ends, as a rule, require to be secured. The facial vein is only in contact with the artery near the lower border of the jaw ; on the face it is sepa- rated fi'om it by a considerable interval. The vein is not so flaccid as are most supei*ficial veins; it remains more patent after section, it possesses no valves, and communicates at one end indirectly with the cavernous sinus, and at the other with the internal jugular vein in the neck. This vein has also another, but less direct, communication with the intracranial veins. It is as follows : the facial vein receives the " deep facial vein " from the pterygoid plexus, and this plexus communicates with the cavernous sinus by means of some small veins which pass through the foramen ovale and the tibrous tissue of the foramen lacerum medius. These dispositions of the facial vein may serve to explain the mortality of some inflamma- tory a flections of the part. Thus, carbuncle of the face is not unfrequently fatal by inducing thrombosis of the cerebral sinuses, and a like complication may occur in any other diSuse and deeply- extending inflammatory condition. The unusual patency also of the facial vein favours septic absorj)tion, and its direct commu- nication ^vith the great vein in the neck may explain those abrupt deaths from thrombosis that have fol- lowed upon the injection of facial nsevi in infants. Nerve §npply. — The nerves of the face are very liberally distributed, the lifth being the sensory nerve, the facial the motor. It follows, from the great number of nerve filaments about the part, that severe irritants applied to the face may set up a widespread nerve disturbance. Dr. George Johnson mentions a case where a piece of flint embedded in a scar on the cheek set up facial neuralgia, facial paralysis, and trismus, and induced a retui-n of epileptic attacks. The 86 Surgical Applied Anatomy. [Chap.vii. positions of the supra and infraorbital foramina and of the mental foramen are indicated as follows. The supraorbital foramen is found at the junction of the inner with the middle third of the upper margin of tlie orbit. A straight line drawn downwards from this point so as to cross the gap between the two bicus- pids in both jaws, will hit both the infraorbital and mental foramina. The infraorbital foramen is a little over a quarter of an inch below the margin of the orbit. The dental foramen in the adult is midway between the alveolus and the lower border of the jaw, and is a little over a quarter of an inch below the cul-de-sac of mucous membrane between the lower lip and jaw. At puberty the foramen is nearer to the lower border of the maxilla, and in old age it is close to the alveolus. The infraorbital nerve has been divided for neuralgia at its point of exit, the nerve being reached either by external incision or through the mouth by lifting up the cheek. In other cases the floor of the orbit has been exposed, the infraorbital canal (the anterior half of which has a bony roof) has been opened up, and large portions of the trunk of the nerve have been in this way resected. The inferior dental nerve has been divided at the mental foramen by an incision made through the mucous membrane. Its trunk has been reached and a part excised through a trephine hole made in the body of the lower jaw. It has been divided also before its entry into the dental foramen in the following manner : The mouth being held widely open, an incision is made from the last upper molar to the last lower molar just to the inner side of the anterior border of the coronoid process. The cut passes through the mucous mem- brane down to the tendon of the temporal muscle. The finger is introduced into the incision, and passed between the ramus of the jaw and the internal ptery- goid muscle until the bony point is felt that marks the Chap. VII.] The Parotid Region. 87 orifice of the dental canal. The nerve is here picked up with a hook, isolated, and divided. The buccal nerve may be the seat of severe neu- ralgia, and may be thus divided through the mouth : " The surgeon places the finger-nail upon the outer lip of the anterior border of the ascending ramus of the lower jaw at its centre, and divides in front of this border the mucous membrane and the fibres of the buccinator vertically. He then seeks for the nerve, separating the tissues with a director, and divides it " (Stimson). The malar bone. — Such is the firmness of this bone, and so direct is its connection with the skull, that violent blows upon it are very apt to be associated with concussion. Resting as it does upon com- paratively slender bones, it is very rare for the malar bone to be broken alone. It may, indeed, be driven into the superior maxillary bone, fracturing that structure extensively, without being itself in any way damaged. A fracture of the malar bone may lead to an orbital ecchymosis, precisely like that which often attends a fracture of the skull base. 2. The parotid region.— The main part of the parotid gland is lodged in a definite space behind the ramus of the lower jaw. This space is increased in size when the head is extended, and when the inferior maxilla is moved forwards, as in protruding the chin. In the latter movement, the increase in the anteroposterior direction is equal to about three-eighths of an inch. It is diminished when the head is flexed. When the mouth is widely opened the space is diminished below, while it is increased above by the gliding forwards of the condyle. These facts should be borne in mind in operating upon and in exploring the parotid space. It will be found also that in inflammation of the parotid much pain is produced by all those move- ments that tend to narrow the space occupied by the 88 Surgical Applied Anatomy. [Chap. vii. gland. The obliquity of the ramus of the jaw in infancy and old age causes the lower part of the space to be, in the former instance relatively, and in the latter instance actually, larger than it is in the adult. The gland is closely invested by 2. fascia derived from the cervical fascia. The superficial layer of the parotid fascia is very dense, is continuous behind with the fibrous sheath of the sterno-mastoid, and in front with that of the masseter. Above it is attached to the zygoma, while below it joins the deej) layer. The deep layer is slender, is attached to the styloid process, forms the stylo-maxillary ligament, and is connected with the sheaths of the pterygoid muscles and the pterygoid process. The gland is, therefore, encased in a distinct sac of fascia, which is entirely closed below, but is quite open above. Between the anterior edge of the styloid process and the posterior border of the external pterygoid muscle there is a gap in the fascia, through which the parotid space communi- cates with the connective tissue about the pharynx. It is well known that in post-pharyngeal abscesses there is very usually a parotid swelling, and in several instances the pus, or at least some portion of it, has been evacuated in the parotid region. In these cases the matter most probably extends from the pharyngeal to the parotid region, through the gap just described. From the disposition of the fascia it follows that very great resistance is offered to the progress of a loarotid abscess directly outwards through the skin. The abscess often advances upwards to the temporal, or zygomatic fossse, in the direction of least resistance, altliough progress in that line is resisted by gravity. It frequently makes its way towards the buccal cavity or pharynx, or it may break through the lower limits of the fascia and reach the neck. It must be borne in mind that the gland is in direct contact with the cartilaginous meatus, with the ramus Chap. VIM The Parotid Regiox. 89 of the jaw and other bony parts, and is closely related with the teniporo-maxillary joint. Thus, a Fig. 13.— A Horizontal Section through the Face and Neck just above the level of the Lower Teeth (Braone). a. Orbicularis oris and, behind it, the buccinator ; 6, internal pterygoid ; c, mas- set er ; d, stylo-glossus, stylo-rharyneeus, and styloid process; e, splenius capitis ;/, digastric ; g, sterno-mastoid ; /i, obliquus superior: i, traobtlo- mastoid ; j, biventer cervicisand complexus ; *, trapezius ; I. tonsil ; wi. facial artery ; n, facial vein ; 0, gustatory nerve ; p, inferior dental nerve and artery ; q, styloid process ; r, external carotid artery ; *, internal carotid artery ; t, vasus ; if, parotid gland ; i, internal jugular vein, with the vagus, spinal accessory, and hypo-glossal nerves to us inner side ; y, vertebral arter>' ; s* odontoid process; 1, occipital artery. 90 Surgical Applied Ana tomy. [Chap. vii. parotid abscess has burst into the meatus, has led to periostitis of the bones adjacent to it, and has incited inflammation in the joint of the lower jaw. In several cases reported by Yirchow, the pus appears to have found its way into the skull along branches of the fifth nerve, for the environs of the Gasserian ganglion were found infiltrated with pus. The auriculo-temporal and great auricular nerves sup- ply the gland with sensation, and the presence of these nerves, together with the unyielding character of the parotid fascia, serve to explain the great pain felt in rapidly-growing tumours and acute inflammation of the gland. The pain is often very distinctly referred along the course of the auriculo-temporal nerve. Thus, a patient with a parotid growth, recently under my care, had pain in those parts of the pinna and temple supplied by the nerve, pain deep in the meatus, at a spot that would correspond to the entrance of the meatus branch of the nerve, and pain in the joint of the lower jaw, which is supplied by the auriculo- temporal. The most important structures in the gland are the external carotid artery, with its two terminal branches, and the facial nerve. The artery, as Tillaux has pointed out, is behind the ramus of the jaw, as high up as the junction of the inferior with the middle third of its posterior border. It then enters the parotid gland, and, passing a little back- wards and outwards, comes nearer to the surface, and at the level of the condyle of the jaw breaks into its two terminal branches. The artery, there- fore, does not enter the gland at its inferior border, and is not in actual relation with the parotid space at its lowest part. The vessel, moreover, is not parallel with the edge of the ramus, but passes through the parotid gland with some obliquity. The facial nerve is represented by a line drawn Chap. VII.] The Parotid Region, 91 across the gland, in a direction forwards and a little downwards from the spot where the anterior border of the mastoid process meets the ear. The nerve is not quite so intimately bound up in the gland as is the carotid artery, and in rapidly-growing tumours of the gland facial paralysis from pressure upon this nerve is not uncommon. It follows, from these and other relations of the parotid, that its entire removal as a surgical procedure is an anatomical impossibility. In opening a parotid abscess, a cut is usually made over the angle of the jaw, and a director pushed upwards into the substance of the gland, after the plan advised by Hilton. The gland is separated by a mere layer of fascia from the internal carotid artery, the internal jugular vein, the vagus, glossopharyngeal, and hypoglossal nerves (Fig. 13). Thus, in stabs in the parotid region it may be difficult at first to tell whether the internal or the external carotid is wounded. It has been suggested that the cerebral hypersemia, sometimes noticed in severe parotitis (mumps), may be due to the pressure of the enlarged gland upon the internal jugular vein, with which it is in the closest contact. Many lymphatic glands are placed upon the sur- face and in the substance of the parotid gland. They receive lymph from the frontal and parietal regions of the scalp, from the orbit, the posterior part of the nasal foss?e, the upper jaw, and the hinder and upper part of the pharynx. When enlarged, these glands may form one species of " parotid tumour." Stenson's duct is about two and a half inches long, and has a diameter of one -eighth of an inch, its orifice being the narrowest part. At the anterior border of the masseter muscle the duct bends suddenly inwards to pierce the buccinator muscle. The bend is so abrupt that the buccal segment of the duct may be almost at right angles 92 Surgical Applied Anatomy. [Chap. vii. with the masseteric. This bend should be taken into consideration in passing a probe along the duct from the mouth. The course of the duct across the masseter is represented by a line drawn from the lower margin of • the concha to a point midway between the ala of the nose and the red margin of the lip. It lies about a finger-breadth below the zygoma, having the transverse facial artery above it and the facial nerve below it. The duct has been ruptured subcutaneously, leading to extravasa- tion of saliva. Wounds of the duct are apt to lead to salivary fistulse. When the fistula involves the buccal segment of the duct it may be cured by opening the duct into the mouth on the proximal side of the fistula. Fistulse of the masseteric segment are, on the other hand, very difficult to relieve. At least one- half of the buccal part of the duct is embedded in the substance of the buccinator muscle. A salivary fistula over the masseter may involve the parotid gland itself, or that part of it known as the socia parotidis. Inflammatory conditions may spread to the parotid from the mouth along Stenson's duct. 3. The upper and lower jaws, and parts connected with them. The saperior maxilla (for antrum, see Nose, page 81 ; for hard palate, see Mouth, page 110). — This bone, on account of its fragility^ and the manner in which it is hollowed out, is very readily fractured. The fracture may be due to direct violence, as by a blow from a " knuckle-duster," or it may be broken by a force transmitted from the lower jaw through the teeth, as in cases of severe blows or falls upon the chin. It may be broken by a blow upon the head, when the chin is fixed; no other bone being damaged ; and, lastly, it may be crushed, as above stated, by the driving in of the malar bone. The displacement of the fragments depends upon the Chap. VII.) The Upper Jaw. 93 direction and degree of the force employed, no muscles having effect. The bone being very vascular, serious injuries, involving great loss of substance, are often wonderfully repaired. Its hollowness, and the cavities that it helps to bound, render it possible for large foreign bodies to be retained in the deeper parts of the face. Thus, Longmore reports "the case of Lieutenant Fretz, of the Ceylon Rifles, who was able to do his military duties for nearly eight years, with the breech and screw of a burst musket lodged in the nares, part of the tail-pin and screw protruding through the hard palate into the mouth." The bone may undergo extensive necrosis, especially in that form of necrosis in- duced in workers in match-factories by exjDosure to the fumes of phosphorus. In one case (^Med. Times, 1862) of necrosis following measles the mischief was limited to the premaxillary, or incisive bone. Excision of the superior maxilla. — The entire bone has been frequently removed when the seat of an extensive tumour, and under certain other conditions. The hony connections to be divided in the operation are the following : (1) The connection with the malar bone at the outer side of the orbit ; (2) the connection of the nasal process with the frontal, nasal, and lachrymal bones ; (3) the connections of the orbital plate with the ethmoid and palate (this plate is often left behind, or is cut through near the orbital margin) ; (4) the connection with the opposite bone and the palate in the roof of the mouth ; and (5) the connection behind with the palate bone, and the fibrous attachments to the pterygoid processes. In the four first-named instances, the separation is effected by a cutting instrument ; in tlie last-named, by simply twisting out the bone. Soft parts divided: These may be con- .aidered under three heads : (1) Tho parts cut in the first 94 Surgical Applied Anatomy. [Chap. vii. incision ; (2) in turning back the flap ; and (3) in sepa- rating the bone. (1) The following are the parts cut in order from above downwards in the usual, or " median," incision, an incision commencing parallel with the lower eyelid, and continued down the side of the nose, round the ala, and through the middle of the upper lip : Skin, superficial fascia, orbicularis palpebrarum, palpebral branches of infraorbital nerve and artery, lev. labii superioris, angular artery and vein, lev. labii sup. alseque nasi, lateralis nasi artery and vein, nasal branches of infraorbital nerve, compressor naris, depressor alee nasi, attachment of nasal carti- lage to bone, orbicularis oris, sup. coronary artery and vein, and mucous membrane of lip. Various branches of the facial nerve to the muscles may be cut. (2) In turning back the flap, the muscles above named will be dissected up, together with the tendo oculi, the levator anguli, the buccinator, a few fibres of the masseter, and, on the orbital plate, the inferior oblique muscle. The infraorbital nerve and artery will be cut as they leave their foramen. In the flap itself will be the trunks of the facial artery and vein, the transverse facial artery, and the facial part of the facial nerve. (3) In separating the nasal process, the lachrymal sac and infratrochlear nerve will be damaged, and the nasal duct and external branch of the nasal nerve cut across. In separating the bones below, the coverings of the hard palate are divided, and the attachment of the soft palate to the palate-bone, unless the removal of that process can be avoided. "Any attempt to dissect off" and preserve the soft covering of the hard palate is futile" (Heath). Posteriorly, the trunk of the infraorbital nerve is again divided (this time in front of Meckel's ganglion), together with the posterior dental and infraorbital arteries, and some branches of the spheno-palatine Chap. VII.] The Lower Jaw. 95 artery. The deep facial vein from the pterygoid plexus will probably be cut, and, lastly, near the palate will also be divided the large palatine nerve and the descending palatine artery. It will be seen that no large artery is divided in the operation. The inferior turbinated bone comes away, of course, with the maxilla. The inferior luaxilla. — Fracture. — This bone is to a great extent protected from fracture by its horse- shoe shape, which gives it some of the properties of a sjiring, by its density of structure, by its great mobility, and by the buffer-like inter-articular carti- lages that protect its attached extremities. The bone is usually broken by direct violence, and the fracture may be in any part. The symphysis is rarely broken, on account of its great thickness. The ramus is pro- tected by the muscular pads that envelope its two sides, and the coronoid process is still more out of the risk of injury, owing to the depth at which it is placed and the protection it derives from the zygoma. The weakest part of the bone is in front, where its strength is diminished by the mental foramen, and by the large socket required for the canine tooth. It is about this part, therefore, that fracture is the most common. The bone may be broken near, or even through, the symphysis by indirect violence, as by a blow or crushing force that tends to approximate the two rami. Thus, the jaw has been broken near the middle line by a blow in the masseteric region. The amount of displacement in fractures of this bone varies greatly, and is nmch influenced by the nature and direction of the force. In general terms, it may be said that, when the body of the bone is broken, the anterior fragment is drawn backwards and downwards by the jaw depressors, the digastric, mylo-hyoid, genio-hyoid, and genio-hyo-glossus ; while the hinder fragment is drawn up by the elevators of the jaw, 96 Surgical Applied Anatomy. [Chap. vii. the masseter, int. pterygoid, and temporal. It must be remembered that the mylo-hyoid muscle will be attached to both fragments, and will modify the amount of displacement. Fractures of the ramus are seldom attended with much displacement, muscular tissue being nearly equally attached to both fragments. In fractures of the body of the bone, the dental nerve often marvellously escapes injury, a fact that is explained by the supposition that the bones are not usually sufficiently displaced to tear across the nerve. Weeks after the accident, however, the nerve has become so compressed by the developing callus as to have its function destroyed. One, or both, condyles have often been broken by falls or blows upon the chin. The gums being firm and adherent, it follows that they are usually torn in fractures of the body of the maxilla, and hence the bulk of the fractures in this part are compound. The temporo- maxillary articulation is supported by a capsule which varies greatly in thick- ness in different parts. By far the thickest part of the capsule is the external part (the external lateral ligament). The internal part is next in thickness, while the anterior and posterior portions of the capsule are thin, especially the former, which is very thin. Thus, Avhen this joint suppurates, the pus is least likely to escape on the external aspect of the articulation, and is most likely to find an exit through the anterior part of the capsule, although this part is to a great extent projected by the attachments of the external pterygoid muscle. Immediately behind the condyle of the jaw are the bony meatus, and, a little to the inner side, the middle ear. In violent blows upon the front of the jaw, these structures may be damaged, and it is interesting to note that the strongest liga- ment of the joint (the external lateral) has a direction Chap. VII.] The Lower Ja^. 97 downwards and backwards, so as to immediately resist any movement of the condyle towards the slender wall of bone that bounds the meatus and tympanum. Were it not for this ligament, a blow upon the chin would be a much more serious accident than it is at present. It follows, from the proximity of the joint to the middle ear, that disease in the articulation may be set up by suppuration in this part. In one case (Holmes' " System of Surgery "), suppurative disease, spreading from the middle ear, not only involved the joint, but induced necrosis of the condyle of the lower jaw. The necrosed condyle was removed entire from the auditory meatus, into which cavity it had projected. Dislocation. — This joint permits only of one form of dislocation, a dislocation forwards. It may be unilateral or bilateral, the latter being the more usual, and it can only occur when the mouth happens to be wide open. Indeed, the dislocation is nearly always due to spasmodic muscular action when the mouth is open, although in some few cases it has been brought about by indirect violence, as by a downward blow upon the low^er front teeth, the mouth being widely opened. It has occurred during yawning, violent vomiting, etc. In more than one case the accident happened while a dentist was taking a cast of the mouth. Hamilton quotes a bilateral dislocation in a woman during the violent gesticulations incident to the pursuit of scolding her husband. When the mouth is widely opened the condyles, together with the interarticular fi bro-cartilage, glide forwards. The fibro-cartilage extends as far as the anterior edge of the eminentia articularis, which is coated with cartilage to receive it. The condyle never reaches quite so far as the summit of that eminence. All parts of the capsule save the anterior are rendered tense. The coronoid process is much depressed. Now if the externa! H 98 Surgical Applied Ana tomy. [Chap. vii. pterygoid muscle (the muscle mainly answerable for the luxation) contract vigorously, the condyle is soon drawn over the eminence into the zygomatic fossa, the interarticular cartilage remaining behind. On reaching its new position it is immediately drawn up by the temporal, internal pterygoid, and masseter muscles, and is thereby more or less fixed. A specimen in the Musee Dupuytren shows that the fixity of the luxated jaw may sometimes depend upon the catching of the apex of the coronoid process against the malar bone. Excision of the inferior maxilla. — Con- siderable portions of the lower jaw can be excised through the mouth without external wound. In excising one entire half of the maxilla a cut is made vertically through the lower lip down to the point of the chin, and is then continued back along the inferior border of the jaw, so as to end near the lobule of the ear, after having been carried vertically upwards in the line of the posterior border of the ramus. The soft parts divided may be considered under three heads : (1) Those concerned in the first incision ; (2) in clearing the outer surface of the bone ; (3) in clearing the inner surface of the bone. 1. (a.) In the anterior vertical cut : Skin, etc., orbicularis oris, inferior coronary and inferior labial vessels, branches of submental artery, levator menti, mental vessels and nerve, some radicles of anterior jugular vein, (h) In the horizontal cut : Skin, etc., platysma, branches of superficial cervical nerve, branches of supram axillary part of facial nerve, facial artery and vein at edge of masseter, and inframax- illary branch of facial nerve (not necessarily divided), (c) The posterior vertical incision would not go down to the bone, and would merely expose the surface of the parotid gland, and part of posterior border of masseter muscle. Chap. VII.] The Lower Jaw. 99 2. In clearing the outer surface the following parts are dissected back : Levator menti, the two depressor muscles, buccinator, masseter (crossed by part of parotid gland, transverse facial vessels, facial nerve and Stenson's duct), masseteric vessels and nerve, temporal muscle. 3. In clearing the inner surface : Digastric, genio- hyoid, genio-hyo-glossus, and mylo-hyoid muscles, a few fibres of superior constrictor, internal pterygoid muscle, inferior dental artery and nerve, mylo-hyoid vessels and nerve, internal lateral ligament, rest of insertion of temporal muscle, mucous membrane. Parts i7i risk 0/ being damaged. — The facial nerve, if the posterior vertical incision be carried too high up. The internal maxillary artery, temporo-maxillary vein, auriculo-temporal nerve (structures all closely related to the jaw condyle), external carotid artery, lingual nerve, the parotid, submaxillary, and sublingual glands. After subperiosteal resection the entire bone has been reproduced. The lower jaw may be entirely absent, or may be of dwarfed dimensions, or be incompletely formed. These conditions are congenital, and depend upon defective development of the maxillary part of the first branchial arch. They are often associated with branchial fistulae, supernumerary ears, macrostoma, and like congenital malformations. With regard to the nerves connected with the jaws little need be said. The upper teeth are supplied by the second division of the fifth, the lower by the third. Some remarkable nerve disturbances have followed, by reflex action, upon irritation of the dental nerves. Thus cases of strabismus, temporary blindness, and wry-neck have been reported as due to the irritation of carious teeth. Hilton gives the case of a man who was much troubled by a carious tooth in the lower jaw (su])plied by the third 100 Surgical Applied Anatomy. [Chap. viii. division of the fifth), and who developed a patch of gray hair over the region supplied by the auriculo- temporal nerve (a branch also of the third division). The muscles of mastication are often attacked by spasm. When the spasm is clonic the chattering of the teeth is produced that is so conspicuous a feature in rigor. When the spasm is tonic the mouth is rigidly closed, and the condition known as trismus, or lockjaw, is produced. Trismus is among the first symptoms of tetanus. It is also very apt to be produced by irritation of any of the sensory branches of the third division of the fifth, since the motor nerve- supply of the muscles themselves is derived from that trunk. Thus trismus is very common in caries of the lower teeth, and during the " cutting " of the lower wisdom tooth. It is much less common in affections of the upper set of teeth, since they are supplied by a more remote division of the fifth nerve. CHAPTEH VIII. THE MOUTH, TONGUE, PALATE, AND PHARYNX. The lips. — The principal tissues composing the lips have the following relation to one another pro- ceeding from without inwards : (1) Skin ; (2) super- ficial fascia ; (3) orbicularis oris ; (4) coronary vessels ; (5) mucous glands ; and (6) mucous membrane. The free border of the lip is very sensitive, many of the nerves having end-bulbs closely resembling tactile corpuscles. The upper lip is supplied with sensation by the second division of the fifth nerve, and the lower lip by the third division. Over these labial nerves a crop of herpes often appears (herpes Chap. VIII.] The Mouth. ioi labialis). The free border of the lower lip is more frequently the seat of epitluilioma than is any other part of the body. The lips contain a good deal of connective tissue, and may swell to a considerable size when inflamed, or oedematous. They are very mobile, and are entu-ely free for a considerable extent from bony attachment of any kind. It follows that destructive inflammations of the lips, and such losses of substance as accompany severe burns, produce much contraction and deformity of the mouth. Contracting cicatrices, also, in the vicinity of the mouth are apt to drag upon the lips, everting them, or producing kindred distortions. It is fortunate that the laxity of the tissues around the mouth, and the general vascu- larity of the part, greatly favour the success of the many plastic operations performed to relieve these deformities. The lips are very vascular, and are often the seat of nsevi and other vascular tumours. The coronary arteries are of large size, and their pulsations can generally be felt when the lip is pinched up. These vessels run beneath the orbicularis oris muscle, and are consequently nearer to the mucous membrane than they are to the skin. When the inner surface of the lip is cut against the teeth, as the result of a blow, these arteries are very apt to be wounded. As such wounds are concealed from view the consequent haemorrhage has sometimes given rise to an erroneous diagnosis. Thus, Mr. Erichsen quotes the case of a drunken man, the subject of such a wound, who, having swallowed, and then vomited, the blood escap- ing from a coronary artery, was for a while supposed to be suffering from an internal injury. As the anas- tomoses between the arteries of the lip are very free, it is usually necessary to tie both ends of the vessel when it has been cut across. The mucous glands in the submucous tissue are I02 Surgical Applied Anatomy. [Chap. viii. large and numerous. From closure of the ducts of these glands, and their subsequent distension, result the " mucous cysts " that are so common about the lips. It has been shown (Holmes' " System of Surgery," vol, ii.) that one form of enlarged lip may depend upon a general hypertrophy of these glands in the submucous tissue. " Hare-lip " is noticed beloAv in connection with the subject of cleft palate. The buccal cavity. — The following points may be noticed in the examination of the interior of the mouth. On the floor of the mouth, and on either side of the frsenum linguse, can be observed a small papilla indicating the orifice of Wharton's duct. The duct of Bartholin (one of the ducts of the sublingual gland) runs along the last part of Wharton's duct, and opens either with it or very near it. Wharton's duct is singularly indistensible, and hence is partly explained the intense pain usually observed when that duct is obstructed by a calcuhis. The near proximity of this duct to the lingual nerve may serve also to account for the pain in some cases. The submaxillary gland can be made out through the mucous membrane at a point a little in front of the angle of the jaw, especially when the gland is pressed up from the outside. On the floor of the mouth, between the alveolus and the anterior part of the tongue, is a well-marked ridge of mucous membrane, that is directed obliquely forwards and inwards to the Whartojiian papilla near the frsenum. It indicates the position of the sublingual gland, and also, so far as it goes, the line of Wharton's duct and the lingual nerve. These structures lie beneath the gland, which is itself covered only by the mucous membrane. The ducts of the sublingual gland, some ten to twenty in number, open into the mouth along the I'idge of mucous membrane just referred to. Kanula, a cystic tumour filled with mucous contents, is often Chap, viii.i The Mouth. 103 met wiUi over the site of the sublingual gland, and is due to the dihxtation of one of the gland ducts that has become obstructed, or to an occluded mucous follicle. The mucous membrane of the Moor of the mouth, as it passes forwards to be reflected on the gums, is attached ne;n" to the upper border of the jaw. The genio-hyo-glossus is attached near the lower border. Between these two parts (the mucous membrane and the muscle) there is, according to Tillaux, a small space lined with squamous epithelium. To this cavity the name is given of the sublingual bursa mucosa. It is constricted in its centre by the fr?enum linguje, and is said to be the seat of mischief in "acute ranula." When the mouth is widely opened the pterygo- maxillary ligament can be readily seen and felt beneath the mucous membrane. It appears as a prominent fold running obliquely downwards behind the last molar teeth. A little below and in front of the attachment of this ligament to the low^er jaw, the gustatory nerve can be felt as it lies close to the bone just below the last molar. This nerve is sometimes divided for the relief of pain in cases of carcinoma of the tongue. Mr. Moore's method of dividing it is as follows : " He cuts the nerve about half an inch from the last molar tooth, at a point where it crosses an imaginary line drawn from that tooth to the angle of the jaw. He enters the point of the knife nearly three-quarters of an inch behind and below the tooth, presses it down to the bone, and cuts towards the tooth " (Stimson). This nerve, as it lies against the bone, has been crushed by the slipping of the forceps in the clumsy extraction of the lower molar teeth. The coronoid process of the lower jaw can be easily felt through the mouth, and is especially distinct when that bone is dislocated. It may be noted that I04 Surgical Applied Anatomy. [Chap. viil a fair space exists between the last molar tooth and the ramus of the inferior maxilla, through which a patient may be fed by a tube in cases of trismus, or anchylosis of the jaw. A congenital cyst is sometimes found in the floor of the mouth between the tongue and the lower jaw, that contains sebaceous matter and hairs. Such cysts ha^'e been supposed to be due to the imperfect closure of the first branchial cleft, the cleft immediately behind the first branchial arch, about which the lower jaw is developed. The glims are dense, firm, and very vascular. In the bleeding that follows the extraction of teeth much of the blood is supplied by them. The gums are particularly afiected in mercurial poisoning, and are also especially involved in scurvy. In chronic lead- poisoning a blue line often appears along their margins. This is due to a deposit of lead sulphide in the gum tissues, which is thus derived : Food debris collected about the teeth in decomposing produces hydrogen sulphide, which, acting upon the lead circulating in the blood, produces the deposit. The blue line, there- fore, is said not to occur in those who keep the teeth clean. The tongue. — On the under surface of the tongue, less than half an inch from the fraenum, the end of the ranine vein can be seen beneath the mucous membrane. Two elevated and fringed lines of mucous membrane may be seen on the under surface of the organ converging towards its tip. They indicate the position of the ranine artery, which is more deeply placed than the vein, close to which it lies. It is extremely rare for the tongue to be the seat of congenital defect. The author of the able monograph on the tongue in Holmes' " System of Surgery " has discovered only one instance of congenital absence of the organ. Fournier gives a case where the tongue was so much Chap. VIII.] The Tongue. 105 longer than usual that the chest could be touched with its tip while the head was held erect. In rare cases the frsenuni linguae may be abnormally short, constituting the condition known as "tongue-tie," which is really a very uncommon affection. The frtenum when divided should be cut as near the jaw as possible, so as to avoid the ranine vessels. Division of these vessels in relieving tongue- tie has led to fatal haemorrhage, the bleeding being encouraged by the efforts of sucking. " If the fra^num and subjacent muscle fibres be too freely divided, energetic sucking on the part of a hungry child may tear the wound of these very lax tissues farther and farther open, until the tongue, having lost all its anterior support, turns over into the pharynx, and is firmly embraced by the muscles of deglutition, which force it down upon the epiglottis, and the latter upon the larynx, until suffocation is produced " (Holmes' " System of Surgery," vol. ii.). In complete anaesthesia, as in that produced by chloroform, when all the muscular attachments of the tongue are relaxed, the organ is apt to fall back and to press down the epi- glottis, so causing suffocation. The tongue is firm and dense, but contains, never- theless, a sufficient amount of connective tissue to cause it to swell greatly when inflamed. Foreign bodies may easily be embedded in its substance. In the Lancet for 184G is noted a case where a portion of a fork is said to have been buried in the tongue for thirty-two years. The surface epithelium is thick, and in chronic superficial inflammation of the organ it often becomes heaped up, forming dense opaque layers — ichthyosis linguse, plaques des fumeurs, leucoma, etc. From the mucous glands, situated chiefly beneath the mucous membrane near the base of the tongue, the mucous cysts are developed that are sometimes met with in this part. io6 Surgical Applied Aiyatojiiv. [Chap. viii. The tongue is very vascular, and is in consequence often the seat of neevoid growths. Its main supply is from the lingual artery. This vessel approaches the organ from the under surface, and as cancer usually shows a tendency to spread towards the best blood- supply, it is to be noticed that carcinoma of the tongue nearly always tends to spread towards the deep attach- ment of the member. At the same time it must be observed that the main lymphatics follow the same course as the main blood-vessels. The vascularity of the tongue is the great bar to its easy removal, haemorrhage being the complication most to be dreaded in such operations. The tongue is well supplied with nerves, that endue it not only with the special sense of taste, but also with common sensation. According to Weber's ex- periments, tactile sensibility is more acute on the tip of the tongue than it is on any other part of the surface of the body. It should be borne in mind that the lingual nerve supplies the forepart and sides of the tongue for two-thirds of its surface, while the glosso-pharyngeal nerve supplies the mucous mem- brane at its base, and especially the papillse vallatse. In painful affections of the tongue in the district sup- plied by the lingual nerve, the patient often is troubled with severe pain deep in the region of the meatus of the ear. The pain in such instances is referred along the course of the third division of the fifth, of which trunk the lingual nerve is a branch. In like manner spasmodic contraction of the masticatory muscles is sometimes found to accompany painful lingual ulcers when involving the region of the gustatory nerve. There would seem to be but little connection between an abscess over the occipital region and wasting of one half of the tongue. But Sir James Paget reports the following case : "A man received an injury to the back of his head that was apparently not severe. In Chap. VIII.] The Tongue. T07 time the right half of the tongue began to waste, and continued to waste until it was less than half the size of the unaltered side. An abscess formed over the occiput, from which fragments of the lower part of the occipital bone were removed. After the removal of all the dead bone the tongue began to recover, and in one month had nearly regained its normal aspect." Here the atrophy was due to wasting of the lingual muscles produced by pressure upon the hypoglossal nerve, which leaves the skull through the anterior condyloid foramen in the occipital bone (Clin. Soc. Trans., vol. iii.). The case illustrates the importance of remembering even small foramina, and the structures they give passage to. The tongue contains much lymphoid tissue, a considerable part of which is massed under the mucous membrane at the posterior part of the organ. The lymphatics also are large and numerous, and for the most part follow the ranine vessels. With regard to glandular infection in lingual cancer, it is well to note that these lymphatics enter one or two small glands lying on the hyo-glossus muscle before they reach the deep glands in the neck, where they finally end. In the strange congenital affection known as macro- glossia the tongue becomes much enlarged, and in some cases may attain prodigious dimensions. Thus, in one case it measured six and a half inches in length and ten inches in circumference. It has protruded so far from the mouth as to reach even to the episternal notch. It has been so large as to deform the teeth and alveolus, and in one case dislocated the jaw. The enlargement is primarily due to the greatly dilated condition of the lymphatic channels of the organ (hence the name, lymphangioma cavernosum, proposed by Yirchow), and to an increased develo|> ment of lymph tissue throughout the part. The io8 Surgical Applied Anatomy. [Chap. viii. portion most conspicuously affected is the base of the tongue, where the lymphatics are usually the most numerous. Excision. — Many different methods have been adopted for the removal of the entire tongue. It has been removed through the mouth by the ecraseur or the scissors, the latter operation being performed with or without previous ligature of the lingual arteries in the neck. It is difficult, however, to fully expose the deeper attachments of the organ through the com- paratively small orifice of the mouth. To obtain more room the cheek has been slit up in one pro- cedure, while the lower lip and symphysis of the lower jaw have been divided in another. In another series of operations the tongue has been reached, or the organ has been fully exposed, by an incision made between the hyoid bone and the inferior maxilla. More recently Kocher has exposed the tongue from the neck, and has reached it by an incision commencing near the ear and following the anterior border of the sterno-mastoid muscle as far as the hyoid bone, Avhence it turns upwards along the anterior belly of the digastric muscle. In the removal of the entire organ, the following parts are of necessity divided : The frsenum, the mucous membrane along the sides of the tongue, the glosso- epiglottic folds, the genio-hyo-glossus, hyo- glossus, stylo-glossus, palato-glossus muscles, the few fibres of the superior and inferior linguales muscles that are attached to the hyoid bone, the terminal branches of the gustatory, glosso-pharyngeal, and hypo- glossal nerves, the lingual vessels, and, at the side of the tongue near its base, some branches of the ascend- ing pharyngeal artery, and of the tonsilar branch of the facial artery. The palate. — The arch of the hard palate varies in height and shape in different individuals, and it Chap. VIII.] The Palate. 109 lias been said that the arch is particularly narrow and high in congenital idiots. The outline of this arch is of some moment in operations upon the palate. Cleft palate. — The palate is often the seat of a congenital cleft. The cleft is precisely in the middle line. It may involve the uvula or the soft palate alone, or may extend forwards and involve the hard palate as far as the alveolus. If it extend beyond the alveolus, the cleft will leave the middle line and will follow the suture between the superior maxillary bone and the os incisivum, appearing therefore between the incisor and canine teeth. Sometimes at the end of the cleft the upper lip is fissured (hare-lip). Hare-lip is never in the middle line, but corresponds to the suture just named, and is therefore opposite the interval between the lateral incisor and canine teeth. Some- times the cleft in the palate on reaching the alveolus will run on either side of the os incisivum, so that that bone is entirely separated from the superior maxilla. Such cases are associated with double hare-lip, and the OS incisi^iim appears as a nodule attached to the nose and suspended in the centre of the gap. The bone in these cases contains, as a rule, the germs only of the centi*al incisoi's, the lateral incisors having been lost in the cleft. Hare-lip very commonly exists without any cleft of the palate. Except in very rare instances, a cleft of the hard palate will not exist without a cleft of the soft. In some cases the os incisivum may be entirely absent, and then the double hare-lip that exists may appear as a large median gap in the lip. When the hard palate is entirely cleft the edges of the cleft are more or less perpendicular, whereas when the cleft is very slight as regards its antero-posterior length, the palate tends to preserve more or less of its normal curv^e. The buccal cavity, when first formed in the foetus, exists as a wide cleft in the face bounded above by the no Surgical Applied Anatomy. [Chap. viii. fronto-nasal process, at the sides by the superior maxil- lary processes, and below by the first visceral arch, around which the lower jaw is formed. The nasal and buccal cavities are one. " The separation of the cavity of the mouth, strictly so called, from the nasal fossae, is effected by the development of the palatal or pterygo-palatal processes of the maxillary plate, which, advancing inwards from the two sides, meet and coalesce with each other and with the septum descend- ing from above in the middle line. . . . When the union of the opposite parts takes place, the naso- palatine canal is left as the vestige of the previous fissures. The median union of the palate begins in front about the eighth week in the human embryo, and reaches the back part, when completed, in the ninth and tenth weeks " (Allen Thomson, in Quain's " Anatomy "). In this way the hard and soft palates are formed, and the upper lip completed ; and it will be under- stood that hare-lip and cleft palate depend simply upon imperfect closure of the foetal gap between the nasal and buccal cavities. The mucous membrane covering the hard palate is peculiar in that it is practically one with the periosteum covering the bones ; and, therefore, in dissecting up this membrane the bone is bared, as the mucous membrane and the periosteum cannot be separated. The membrane is thin in the middle line, but is much thicker at the sides near the alveoli, the increased thickness depending mainly upon the intro- duction of a number of mucous glands beneath the 'surface layers, such glands being absent in the middle line. The density and toughness of the soft covering of the hard palate render it very easy to manipulate when dissected up in the form of flaps in the o^Dera- tion for cleft palate. The main blood-su2:)ply of both the bones of the Chap. VIII.] The Palate. hi hard palate and its" mucous covering is derived from the descending palatine branch of the internal maxil- lary artery. This vessel, which is practically the only vessel of the hard palate, emerges from the posterior palatine canal near the junction of the hard palate with the soft, and close to the inner side of the last molar tooth. The vessel runs forwards and inwards, to end at the anterior palatine canal. Its pulsations on the palate can often be distinctly felt. In dissecting up muco-periosteal flaps from the hard palate, it is most important to make the incision in the mucous mem- brane, close to, and parallel with, the alveolus, so that this artery may be included in the flap and its vitality therefore not be endangered. By such an incision, also, unnecessary bleeding is avoided. In dissecting up the flap it should be remembered that the artery runs much nearer to the bone than to the mucous surface. The soft palate is of uniform thickness, its average measurement being estimated at about a quarter of an inch. When the soft palate is cleft, the edges of the fissure are approximated during swallow- ing by the uppermost fibres of the superior constrictor. This approximation may narrow the cleft to one-third or one-half of its previous size. The muscles that tend to widen the cleft are, in the main, the levator palati and tensor palati. It is necessary that these muscles should be divided before attempting to close the cleft by operation. The levator palati crosses the palate obliquely from above downwards and inwards on its way to the middle line, lying nearer to the posterior than the anterior surface of the velum. The tensor palati turns round the hamular process, and passes to the middle line in a nearly horizontal direc- tion. The hamular process can be felt through the soft palate just behind and to the inner side of the last upper molar tooth. There are three principal methods 112 Surgical Applied Anatomy. [Chap. viii. of dividing these muscles : (1) Ferguson's : A small knife, with the blade at right angles to the stem, is passed through the cleft, and is made to divide the levator palati by an incision on the posterior aspect of the palate, transverse to the direction of the muscla The tensor is not di- vided in this procedure. (2) Pollock's : A thin narrow knife, with the cutting-edge upwards, is introduced into the soft palate a little in front, and to the inner side of the hamular process. The tendon of the tensor muscle is above the knife, and is cut as the knife is pushed upwards and inwards. The knife is inserted until its point jDresents at the upper part of the cleft. As it is being withdrawn, it is made to cut the posterior surface of the velum to a sufficient depth to divide the levator palati (Fig. 14). (3) Bryant's: Here the palate muscles are divided by a cut with the scissors that involves the entire thickness of the velum, the cut being at the side of the velum, and nearly parallel with the cleft. The blood supply of the soft palate is derived from the descending palatine branch of the internal maxil- lary artery, the ascending pharyngeal artery, and the ascending palatine branch of the facial artery. The latter vessel reaches the velum by following the levator palati muscle, and must be divided in the section made of this muscle in the procedures just described. The pliarynx is al^oiit five inches in length. . It is much wider from side to side than from before Fig. 14.— The Muscles of the Soft Palate, from behind. c. Levator palati ; 6, tensor palati ; c, hamular iiro- cess ; d, wall of pharj-nx ; e, azygos uvulae; /, the point of entry of the knife in Pollock's opera- tion ; above it is the line of incision made on with- drawing the knife. Chap. VIII.] The Pharynx. 113 backwards. It is Widest at the level of the tip of the greater corniia of the hyoid bone, where it measures about two inches. It is narrowest where it joins the gullet oi)posite the cricoid cartilage, its diameter here being less than three-quarters of an inch. The pharynx is not so large a space as supposed, for it must be remembered that during life it is viewed very obliquely, and erroneous notions are thus formed of its antero - posterior dimensions. The distance from the arch of the teeth to the com- mencement of the gullet is about six inches, a measurement that should be borne in mind in ex- tracting foreign bodies. Foreign bodies passed into the pharynx are most apt to lodge at the level of the cricoid cartilage, a point that, in the adult, is a little beyond the reach of the finger. The history of foreign bodies in the pharynx shows that that cavity is very dilatable, and can accommodate for some time large substances. Thus, in a case reported by Dr. Geoghegan, a man of sixty, who had for months some trouble in his throat for which he could not account, was supposed to have cancer. On examination, how- ever, a plate carrying five false teeth, and presenting niches for five natural ones, was found embedded in the pharynx, where it had been lodged for five months. The plate had been swallowed during sleep {Med. Press, 1866). In the Lancet for 1868 is an account of a mutton chop that became lodged in the pharynx of a gluttonous individual. The chop presented the ordinary vertebral segment of bone, together with one and a half inches of rib, and was " pretty well covered with meat." At- tempts to remove it failed, and it was finally vomited up. Among the strangest foreign bodies in this part, are live cat-fish, that are said to have jumped into the mouths of bathers while swimming. Dr. Norman Chevers ("Manual of Med. Jurisprudence I T 1 4 Surgical Applied Ana tomv. [Chap. viii. for India") quotes: "Natives of India are not in- frequently brought to hospital dying of suflfocation and alarm, with a large cat-fish impacted in the fauces." In one case (^Indian Med. Gaz., 1878) the fish had thought fit to take a firm hold of the uvula, and declined to leave go until its head had been pinched with forceps. The walls of the pharynx are in relation with the base of the skull, and with the upper six cervical vertebrae. The arch of the atlas is almost exactly on a line with the hard palate. The axis is on a line with the free edge of the upper teeth. The termination of the pharynx corresponds to the sixth cervical vertebra. The upper vertebrae can be examined, as regards their anterior surface, from the mouth. When the bones about the pharynx are diseased, the necrosed parts may be discharged by that cavity. Thus por- tions of the atlas and axis have been expelled by the mouth, as have also been some fragments of compara- tively large size thrown ofi* by the occipital and sphenoid bones. The mucous membrane of the pharynx is vascular, and readily inflamed ; and such inflammations are peculiarly dangerous, in that they may spread to the lining membrane of the larynx. Much adenoid tissue is distributed in the mucous membrane of the pharynx, and it is this tissue that is the primary seat of inflam- mation in scrofulous pharyngitis. The tissue imme- diately outside the pharynx walls is lax, and favours the spread of efiusion. Thus, in acute inflammation of the pharynx, the effusion has been found to extend along the oesophagus, reaching the posterior mediastinum, and advancing even to the diaphragm. In the lax connective tissue between the pharynx and the spine abscess is not infrequent, due, as a rule, to caries of the vertebrae (post-pharyngeal abscess). In this con- nective tissue, and opposite the axis, is also found a Oiap. viiT.] The Pharynx. 115 lymphatic gland that receives lymphatics from the nares. This gland may prove the seat of a suppura- tion. Such collections may so push forw^ard the pos- terior pharyngeal wall as to depress the soft palate, or may cause severe dyspnoea by interference with the larynx. The matter may discharge itself through the mouth, or may reach the neck by passing behind the great vessels and the parotid gland, presenting ulti- mately beneath or at one border of the sterno-mastoid muscle. jNIany structures of importance are in relation with the lateral walls of the pharynx, the principal being the internal carotid artery, the vagus, glosso-pharyngeal, and hypoglossal nerves. The internal carotid is so close to the pharynx that its pulsations may be felt by the finger introduced through the mouth. These, and other deep structures in the neck, may be wounded by foreign bodies, that, passing in at the mouth, have been thrust through the pharynx into the cervical tissues. The internal jugular vein is at some distance from the pharynx, especially at its upper part (Fig. 13). Langenbeck has three times extirpated the pha- rvnx for malignant disease, but without success. He reaches it from the neck through an incision, that, beginning below the jaw, midway between the sym- physis and angle, is carried over the great cornu of the hyoid bone, and ends close to the cricoid cartilage. The posterior belly of the digastric and the stylo-hyoid muscles are detached from the hyoid bone, while the omo-hyoid muscle, the lingual, facial, and superior thyroid arteries, and the superior laryngeal nerve are divided. The tonsil is lodged between the anterior and posterior palatine arches. It is in relation externally "w-ith the superior constrictor muscle, and corresponds, as regards the surface, to the angle of the lower jaw. It is questionable whether the enlarged tonsil, when ii6 Surgical Applied Anatomy. [Chap. viii. it is the subject of other than malignant enlargement, can ever be felt externally. When hypertrophied, the mass tends to develop towards the middle line, where no resistance is encountered, and to effect but little change in its external relations. The mass, often mis- taken for the enlarged tonsil in the neck, is formed of enlarged glands, situate near the tip of the great cornu of the hyoid bone. These glands receive the tonsillar lymphatics, and are almost invariably enlarged in all tonsil affections. It must be remembered that many structures are interposed between the tonsil and the skin, and as the hypertrophied body projects freely into the pharyngeal cavity, one would not expect that it could be readily felt, even were the interposed tissues less extensive than they are. The tonsil ia closely enough attached to the pharyngeal wall to be affected by the movements of the pharyngeal muscles. Thus it is moved inwards by the superior con- strictor muscle during the act of swallowing, and may be drawn outwards, on the other hand, by the stylo- pharyngeus muscle. The ease with which a tonsil can be reached depends, other things being equal, upon the extent to which it can be withdrawn by the stylo- pharyngeus, and upon the development of the anterior ])alatine arch, which, to some extent, hides the tonsil. A child with a prominent anterior palatine arch, con- taining a well-developed palato-glossus muscle, and with a vigorous stylo-pharyngeus, can for a long time elude the tonsil guillotine. Deafness is often complained of when the tonsil is hypertrophied. This is not due to closure of the Eustachian tube by the direct pressure of the enlarged mass. Such pressure is anatomically impossible. The large tonsil may, however, affect the patency of the tube, by disturbing the soft palate, and through it the tensor palati muscle, which is much concerned in keep- ing open the Eustachian tube. The deafness in these Chap. VII i.i The Pharynx. 117 cases is probably due rather to an extension of the hypertrophic process to the lining membrane of the tube than to any pressure effects, since it is usually not improved until some time after the tonsil has been removed. The tonsil tissue is for the most part collected around a number of recesses. The decom- position of retained epithelial structures within those recesses produces the foetid breath often noticed in cases of enlarged tonsil, and probably incites the attacks of inflammation to which such tonsils are liable. The tonsil is very vascular, receiving blood from the tonsillar and palatine branches of the facial artery, from the descending palatine branch of the internal maxillary, from the dorsalis linguje of the lingual and from the ascending pharyngeal. Hence the operation of removing the tonsil is often associated with free bleeding. The internal carotid artery is close to the pharynx, but is some way behind the gland (Fig. 13). The vessel is, indeed, about four-fitths of an inch posterior to that body, and is in comparatively little danger of being wounded when the tonsil is ex- cised. The internal jugular vein is a considerable distance from the tonsil. Of important cervical struc- tures, the nearest to the tonsil is the glosso-pharyngeal nerve. The ascending pharyngeal artery is also in close relation with it. Although of small size, bleed- ing from this vessel has proved fatal, as the following interesting case, reported by Mr. Morrant Baker, will show : A man, aged 23, fell Avhen drunk, and grazed his throat with the end of a tobacco-pipe he was smokinor at the time. He thouiiclit nothing of the accident. In two days he came to the hospital with what appeared to be an acutely-inflamed tonsil. The tonsil was punctured, but nothing escaped save a little blood. Severe haemorrhages occurred from the tonsil wound, and on the fourth day after the accident ii8 Surgical Applied Anatomy. [Chap. ix. one inch of the stem of a clay pipe was discovered deeply embedded in the glandular substance. It was removed, and the common carotid tied. The patient, however, never rallied from the previous severe hae- morrhages, and soon died. The autopsy showed that the stem of the pipe, which had not been missed by the patient, had divided the ascending pharyngeal artery (St. Bart.'s Hosp. Keports, 1876). CHAPTEE IX. THE NECK. Surface anatomy. — Bony points. — The hyoid bone is on a level with the fourth cervical vertebra, while the cricoid cartilage is opposite the sixth. The upper margin of the sternum is (during expiration) on a level with the disc between the second and third dorsal vertebrae. At the back of the neck there is a slight depression in the middle line which descends from the occipital protuberance, and lies between the prominences formed by the trapezius and complexus muscles of the two sides. At the upper part of this depression the spine of the axis can be made out on deep pressure. Below this, the bony ridge formed by the spines of the third, fourth, fifth, and sixth cervical vertebrae can be felt, but the individual spines cannot usually be distinguished. At the root of the neck the spinous process of the vertebra prominens is generally very obvious. The transverse process of the atlas may be felt just below and in front of the tip of the mastoid process. By deep pressure in the upper part of the supraclavicular fossa, the transverse process of the seventh cervical vertebra can be distinguished. If Chap. IX.] The Neck. 119 deep pressure be made over the line of the carotid vessels at the level of the cricoid cartilage, the promi- nent anterior tubercle of the transverse process of the sixth cervical vertebra can be felt. This is known as the " carotid tubercle." The carotid artery lies directly over it, and in ligaturing that vessel some surgeons make important use of this tubercle as a landmark. If a horizontal section of the neck, in a muscular subject, taken about the level of the sixth cervical vertebra, be viewed, it will be observed that the whole of the body of the vertebra divided will lie within the an- terior half of the section. The miclclle line. — In the receding angle below the chin the hyoid bone can be felt, and its body and greater cornua well made out. About a finger's breadth below it is the thyroid cartilage. The details of this latter are readily distinguished, and below it the cricoid cartilage, crico-thyroid space, and trachea can be easily recognised. The separate rings of the trachea cannot be felt. The trachea is less easily made out, as it passes down the neck. As it descends it takes a deeper position, and at the upper border of the sternum lies nearly one and a half inches from the surface. The rima glottidis corresponds to the middle of the anterior margin of the thyroid cartilage. Unless enlarged, the thyroid gland cannot be made out with certainty. Accoi-ding to Mr. Holden, the pulse of the superior thyroid artery can be felt at its upper and anterior part. The anterior jugular veins descend on either side of the middle line upon the sterno -hyoid muscles. They commence in the submaxillary region, pierce the fascia just above the inner end of the clavicle, and, passing behind the origin of the sterno -mastoid muscle, are lost to view. The inferior thyroid veins lie in front of the trachea, below the isthmus. I20 Surgical Applied Anatomy. [Chap. ix. The side of tlie neck. — Muscles. The sterno- mastoid muscle, especially in thin subjects and when thrown into action, is a prominent feature in the neck. The anterior border of the muscle is very distinct. The posterior border is less prominent, especially at its upper part. A communicating branch from the facial vein generally runs along the anterior border of the muscle to meet the anterior jugular vein at the lower part of the neck. The interval between the sternal and clavicular parts of the muscle is generally well marked. If a needle be thrust through this interval, quite close to the clavicle, it would just touch the bifurcation of the innominate arteiy on the right side and would pierce the carotid vessel on the left. The posterior belly of the digastric muscle corresponds to a line drawn from the mastoid process to the anterior part of the hyoid bone. The anterior belly of the omo-hyoid follows an oblique line drawn downwards from the fore-part of the hyoid bone, so as to cross the line of the carotid artery opposite the cricoid cartilage. The posterior belly can be made out in thin necks, especially when in action, running nearly parallel with and just above the clavicle. Although not taking quite the same direction, yet the posterior borders of the sterno-mastoid and anterior scalene muscles practically correspond to one another. Vessels. — The common carotid artery is represented by a line drawn from the sterno-clavicular joint to a point midway between the angle of the jaw and the mastoid process. The vessel bifurcates at the upper border of the thyroid cartilage. The omo-hyoid crosses it opposite the cricoid cartilnge, and at about the same level the artery is crossed by the middle thyroid vein. The line of the internal jugular vein is just external to that for the main artery. The superior thyroid artery comes off just below the great cornu of the hyoid bone, and curves forwards and Chap. IX.] The Neck. 121 downwards to the upper edge of tlie thyroid cartiLige. The lingual arises opposite the tip of the great cornu, and ruus just above that process on its way to tlie tongue. The facial artery is very tortuous, but its general course in the neck is represented by a line drawn from the anterior border of the masseter at the lower border of the jaw to a point just above the tip of the great cornu, while the occipital follows a line that starts from the latter point and runs across the base of the mastoid process. The external jugular vein follows a line drawn from the angle of the jaw to the middle of the clavicle. The subclavian artery describes a curve at the base of the posterior triangle. One end of the curve corresponds to the sterno-clavicular joint, the other end to the centre of the clavicle, the summit of the curve rising to a point about half an inch above that bone. In the angle between the posterior edge of the sterno-mastoid and the clavicle the pulsations of the artery may be felt. Just above tlie bone the artery may be compressed against the first rib. The compression is most easily applied when the arm is well di-awn down, and the direction of the pressure should be downwards and inwards. The subclavian vein lies below the artery, and is entirely under cover of the clavicle. The suprascapular and transverse cervical arteries run parallel with the clavicle, the former quite behind the bone, the latter just above it. The pulsations of the latter vessel can generally be felt. Nerves. — The position of the chief superficial nerves of the neck may be fairly indicated by six lines, all drawn from the middle of the posterior border of the sterno-mastoid muscle. A line drawn forwards from this spot so as to cross the sterno-mastoid at right angles to its long axis, corresponds to the super- ficial cervical nerve. A second line drawn up across 122 Surgical Applied Anatomy. [Chap. ix. the muscle to the back of the pinna, so as to run parallel with the external jugular vein, corresponds to the great auricular nerve ; and a third line, running along the posterior border of the sterno-mastoid muscle to the scalp marks the course of the small occipital nerve. These lines, continued downwards, so as to cross the sternum, the middle of the clavicle, and the acromion, will indicate respectively the supra- sternal, supraclavicular, and supra-acromial nerves. The spinal accessory nerve reaches the anterior border of the sterno-mastoid muscle at a point about one inch below the tij) of the mastoid process. It emerges from beneath that muscle about the middle of its posterior border, crosses the posterior triangle, and passes beneath the edge of the trapezius at a spot on a level with the spine of the vertebra prominens. The j^hrenic nerve commences deeply at the side of the neck, about the level of the hyoid bone, and runs downwards to a point behind the sternal end of the clavicle. About the level of the cricoid cartilage it lies beneath the sterno-mastoid (which covers it wholly in the neck) about midway between the anterior and posterior borders of the muscle. The brachial plexus can be felt, and even seen in very thin sub- jects. Its upper limits may be represented by a line drawn across the side of the neck from a point about opposite to the cricoid cartilage, to a spot a little ex- ternal to the centre of the clavicle. The neck. — The skin in the submaxillary region is lax and thin, and is often found of considerable value for making flaps in plastic operations about the mouth. The platysma myoides is closely connected with the skin, and to its action is due the turning-in of the edges of such wounds as are athwart the line of direction of the muscle. The amount of subcu- taneous fat in the cervical region varies in different parts. In the suprahyoid region it is apt to undergo Chap. IX.] The Neck. 123 extensive development, producing the diffused lipoma known as " double-chin." The skin over the nape of the neck is very dense and adherent, and these two circumstances, in addition to the free nerve-supply of the parts, serves to explain the severe pain that often accompanies inflammation in this region. Anthrax, or carbuncle, is very commonly met with at the root of the neck, in the middle line. Why it especially selects this spot it is difficult to say. It may be noted, however, that this region has no very extensive blood supply, that the middle line of the body is in all parts of comparatively slight vascularity, and that at the nape of the neck covered and uncovered parts of the body meet, so that the spot is liable to considerable fluctuations of temperature. Setons and issues were, in less recent times, often applied to the dense integuments at the back of the neck, just below the occiput. These measures were accredited with not infrequently producing tetanus, and, in such cases, it is probable that the nerve irritation started in the great occipital nerve. When the steriio-mastoid muscle of one side is rigidly contracted, either from paralysis of the opposite muscle or from spasmodic contraction, or from some congenital defect, the condition known as wry-neck is produced. The position of the head in wry-neck illustrates precisely the effect of the sterno-mastoid when in full action. The head is bent a little forwards, the chin is turned towards the sound side, and the ear on the affected side leans towards the sterno - clavicular joint. In many cases the trapezius and scalene muscles are also affected. Spasmodic contraction of the muscle may be due to reflex irritation. Thus, it has accompanied inflam- mation of the cervical glands in the posterior triangle. Such inflammation has irritated some branches of tha 124 Surgical Applied Anatomy. [Chap. ix. cervical plexus, and the sterno- mastoid muscle, although it is suj^plied mainly by the spinal accessory nerve, receives a nerve from that plexus (viz., from the second cervical). The course of the reflex dis- turbance in such cases is therefore not difiicult to follow. A like contraction has also been produced by direct irritation of the second cervical nerve in cases of disease of the first two cervical vertebrae. For the relief of some forms of wry-neck, the sterno- mastoid muscle is divided subcutaneously, as in an ordinary tenotomy operation, about half-an-inch above its attachment to the sternum and clavicle. Two structures stand considerable risk of being wounded in this operation, viz., the external jugular vein lying near the posterior border of the muscle, and the ante- rior jugular which follows its anterior border, and passes behind the muscle, just above the clavicle, to terminate in the first-named vein. With common care, there should be no risk of wounding the great vessels at the root of the neck. There is a curious congenital tumour, or indura- tion, sometimes met with in this muscle in the newly born. It is usually ascribed to syphilis, but, in most cases, is probably due to some tearing of the muscle fibres during the process of delivery. The cervical fascia. — The layers of fascia that occupy the neck, and that are known collectively as the deep cervical fascia, are dense structures, having a somewhat complex arrangement and a great amount of importance from a surgical point of view. This fascia limits the growth of cervical tumours and abscesses, and modifies the direction of their progress, but I do not think that its effect in this matter is quite so definite as is usually maintained. It is true that deep-seated cervical abscesses are often found to follow just such a course as t]ie arrangement of the fasciae would lead us to suppose, while, on the other Chap. IX.] The Cervical Fascia. 125 liand, instances are by no means uncommon where the abscess or growth appears to ignore these membranes and adopt a course of its own. The deep cervical fascia may be divided into («) the superficial layer, and (6) the deeper processes. {a) The superficial layer forms a complete investment for the neck, and covers in all tlie cervical structures, excepting the platysma and some superficial veins and nerves, with the completeness of a perfectly-fitting cravat. It commences behind at the sjDinous processes of the vertebra, and, having invested the trapezius muscle, starts, at the anterior border of that muscle, as a single layer, to cross the posterior triangle. Ar- riving at the posterior border of the sterno-mastoid muscle, it splits, to enclose that structure, appealing again as a single layer at the anterior border of the muscle, from whence it passes to the middle line of the neck to join the fascia of the opposite side, entirely covering in on its way the anterior triangle. The part that occupies the posterior triangle \t attached above to the mastoid process and superior curved line of the occipital bone, and below to the clavicle, so that the space is completely closed in by the fascia in all parts, although, just above the clavicle, it is pierced by the external jugular vein on its way to the deeper trunks. Over the anterior triangle, the fascia is attached above to the border of the lower jaw. Behind that bone it passes over the parotid gland to the zygoma, forming the parotid fascia, while a deeper layer passes beneath the gland (between it and its submaxillary colleague), to be attached to points at the base of the skull. It is from this deeper part that the stylo-maxillary ligament is developed. In front the fascia is attached to the hyoid bone, and just below the thyroid body it divides into two layers again, one to be attached to the front of the sternum, and the other to the back. 126 Surgical Applied Anatomy. [Chap. ix. Both these layers lie in front of the depressors of the hyoid bone, and they form between them a little space (which extends so far laterally as to enclose the sternal head of the sterno-mastoid), the widest part of which is below, and which there corresponds in width Fig. 15. — Transverse Section through the lower part of the Neck, to show the arrangements of the Cervical Fascia (Diagrammatic). /7, Trapezius; 6, sterno-mastoid; c, depressors of hyoid tone; a, platysma; e, anterior spinal muscles ; /, scalenus anticus ; g, carotid artery ; ft, external juguiar vein ; i, posterior spinal muscles ; t, trachea, with gullet behind and thyroid body in front. to the thickness of the sternum. It will be perceived that, in dividing the sternal head of the sterno- mastoid, the operation is performed within this little chamber formed by the two layers just named, and it is well to note that the anterior jugular vein also occupies this chamber on its way to the external jugular trunk. This superficial layer of the fascia, considered generally, would oppose in all parts the Chap. IX.] The Cervical Fascia. 127 progress of abscesses" or growths towards the surface, and would encourage or compel them to take a deeper position. (6) The deeper processes. (1) From tlie super- ficial layer, a process comes off near the anterior border of the sterno-raastoid muscle, which, passing beneath the depressors of the hyoid bone, invests the thyroid body and front of the trachea, and passes down, in front of that tube and of the large vessels, to the fibrous layer of the pericar- dium. (2) The prevertebral fascia is a layer that descends on the prevertebral muscles behind the pharynx and gullet. It is attached above to the base of the skull, and, below, descends into the thorax, behind the oesophagus. Laterally, it joins the carotid sheath, and is then prolonged outwards and down- wards over the scalene muscles, the brachial plexus, and subclavian vessels. It follows these vessels beneath the clavicle, where it forms the axillary sheath, and becomes connected with the under surface of the costo-coracoid membrane. (3) The sheath of the carotid artery and its accompanying vein and nerve are derived in part from fascia No. 1, and in part from fascia No. 2. The effects of this disposition of the fascia may be illustrated by noting the course probably taken by cervical abscesses in various positions. (1) An abscess in the posterior triangle will be bounded towards the surface by the superficial layer of fascia. Towards tiie floor, or deep part, of the triangle it will be bounded by the lateral portion of fascia No. 2. The abscess may extend some way under the clavicle until arrested by the union of the costo-coracoid membrane with fascia No. 2. It would readily extend under the edge of the trapezius muscle, and could pass beneath the sterno-mastoid muscle and carotid artery to the anterior and deeper parts of the neck. (2) An abscess 128 Surgical Applied Anatomy. [Chap ix. in the anterior triangle in front of the depressors of the hyoid bone would probably come forward, owing to the thinness of the fascia in front of it ; but, if pent up, it would tend to progress towards the anterior mediastinum, or into the lateral parts of the neck in front of the carotid vessels. (3) An abscess behind the hyoid depressors and about the trachea or thyroid body, or in the immediate vicinity of the carotid vessels (an abscess situate, in fact, between the deep fasciae ISTos. 1 and 2) would find itself in a narrow strait, and, after pressing much upon adjacent parts, would most readily spread down- wards into the mediastinum. (4) An abscess imme- diately in front of the spine, and beneath the deep fascia No. 2, might extend down into the posterior mediastinum, or move towards the posterior and lateral parts of the neck, following the brachial plexus, and so reach the posterior triangle, or even the axilla. In many cases a cervical abscess has burst into the gullet, or trachea, and even into the pleura. In some instances the great vessels have been opened up. In one remarkable case reported by Mr. Savory (Med. Chir. Trans., 1881), not only was a considerable portion of the common carotid artery destroyed by the abscess, but also a still larger portion of the internal jugular vein, and a large part of the vagus nerve. This, and like examples of the destructive action of some cervical abscesses, depend, no doubt, upon the unyielding character of the cervical fascia, which hems in the pus on all sides, and drives it to resort to desperate measures to effect an escape. " It is noteworthy," remarks Mr. Jacobson, " that communications between abscesses and deep vessels have usually taken place beneath two of the strongest fasciae in the body, the deep cervical fascia and the fascia lata " (Hilton's " Rest and Pain "). Chap, ix-i -Cut Throat. 129 Cut throat and wounds of the neck. — The skin of the neck is so elastic and mobile that it is readily th^o^^^l into folds when a knife, and especially a blunt knife, is drawn across it. Thus, in cases of cut throat several distinct skin-cuts may be found that were all produced by one movement of the knife. The wound in cut throat, whether suicidal or homi- cidal, most frequently involves the thyro - hyoid membrane, next in frequency the trachea, and then the thyroid cartilage. 1. If the wound be above the hyoid bone the following parts may be cut : Anterior jugular vein ; anterior belly of digastric ; mylo-hyoid, genio-hyoid, genio-hyo-glossus, and hyo-glossus muscles ; the lingual aiteiy : branches of the facial artery ; the hypoglossal and gustatory nerves ; the submaxillary gland. The substance of the tongue may be cut, and the floor of tlie mouth freely opened. In any case, where the attachments of the toncjue are divided the organ is apt to fall back upon the larynx and produce suifoca- tion. 2. If the wound be across the thyro-hyoid space the following may be the parts cut : Anterior jugular vein ; sterno-hyoid, thyro-hyoid, omo-hyoid muscles ; thyro-hyoid membrane ; inferior constrictor ; superior laryngeal nerve ; superior thyroid artery ; and if near hyoid bone the trunk of the lingual artery may be cut. The pharynx would be opened in a deep wound, and the epiglottis divided near its base. Division of the epiglottis in wounds in this situation is always a serious complication. 3. If the wound involve the trachea the following may be the parts cut : Anterior jugular vein ; sterno- hyoid, sterno-thyroid, and omo-hyoid muscles ; part of sterno- mastoid ; thyroid gland ; superior and inferior thyroid arteries ; superior, middle, and inferior thyroid veins ; recurrent nerves and the gullet. J 130 Surgical Applied Anatomy. [Chap. ix. In wounds of the neck the great vessels often escape in a marvellous manner. They are protected in part by the depth at which they are situated, and in part by their great mobility, lying as they do in an atmosphere of loose connective tissue. DiefFenbach relates a case of cut throat in which both gullet and trachea were divided without any damage to the great vessels. In cut throat the vessels are greatly protected by the projecting thyroid cartilage above, and by the contracting of the sterno-mastoid muscles below. Deep gashes made across the crico-thyroid space, or through the upper part of the trachea, reach the great vessels more easily than would wounds made with equal force in any other part of the neck. In some cases of gunshot wound the vessels seem to have been actually pushed aside, and to have owed their safety to their mobility. Thus, in a case reported by Longmore, the bullet passed entirely through the neck from one side to the other. It passed through the gullet, damaged the posterior part of the larynx, but left the great vessels intact. In another recorded case a boy fell upon the point of a walking-stick. The end of the stick passed entirely through the neck from side to side, entering in front of one sterno-mastoid muscle, and emerging through the substance of the opposite one. It probably passed between the pharynx and the spine. The boy, who left the hospital well in eighteen days, owed his safety to the laxity of the cervical connective tissue, and to the mobility of the main structures in the neck. In connection with the subject of wounds of the neck it must be remembered that the most important part of the sj^inal cord can be reached from behind, through the gap between the atlas and axis. In this situation the cord has been divided by one stab of a knife, the instrument entering between the two bones. Chap. IX.] The Larynx and Trachea. 131 Langier gives some ingenious cases of infanticide where the lethal weapon was merely a long needle. The needle was introduced into the spinal canal between the atlas and axis, and the cord readily cut across. Wounds at the side of the neck have divided considerable portions of the brachial plexus without involvinsf other structures. The Iiyoid bone may be broken by direct violence, as from blows, or in the act of throttling. It is sometimes found broken in those who have been hanged. The fracture may involve the body of the bone_, but more usually the greater cornu is found broken off. In the NeiD York Medical Record (1882) is the report of the case of a man who felt something snap under his chin while yawning. On examination the hyoid bone was found to be fractured. The bone was also found broken in a patient who threw her head violently backwards to save herself from falling (Hamilton). The fracture is associated with great difficulty and pain in speaking, in mo^'ing the tongue, in opening the mouth, and in swallowing, symptoms that may be readily understood. The larynx and trachea. — With the laryngo- scope the following parts may be made out : The base of the tongue and glosso- epiglottic ligaments ; the superior aperture of the larynx, presenting in front the epiglottis, at the sides the aryteno-epiglottidean folds (in which are two rounded eminences corre- sponding to the cornicula and cuneiform cartilages), and at the back the arytenoid commissure of mucous membrane. Deeply down can be seen the true and false vocal cords, the ventricle, the anterior wall of the larynx, a little of the cricoid cartilage, and more or less of the anterior wall of the trachea. If the glottis be very fully dilated the openings of the two bronchi may be dimly seen. 132 Surgical Applied Anatomy. [Chap. ix. The thyroid and cricoid cartilages, and the greater part of the arytenoid, are in structure hyaline, as are the costal cartilages. Like the last-named, they are liable to become more or less ossified as life ad- vances, and when ossified are liable to be fractured by violence ; the cartilage usually so fractured is the thyroid. The rim a g^lottidis is the aperture between the true vocal cords in front and the bases of the arytenoid cartilages behind. It is the narrowest part of the interior of the larynx, and it is well to be familiar with its proportions in reference to the entrance of foreign bodies, and the introduction of instruments. In the adult male the rima measures nearly one inch (23 millimetres) from before backwards ; from side to side, at its widest part, it measures about 8 mm., and this diameter may be increased to 12 mm. in extreme dilatation. In the female and the male before puberty the antero-posterior diameter is about 17 mm., and the transverse about 4 mm. The mucous membrane of the larynx varies in thickness in different parts, and in the amount of its submucous tissue. The membrane is thickest, and the submucous tissue most abundant, in the following parts, taken in order of degree : The aryteno- epiglottidean folds, the mucous membrane of the ventricle, the false cords, and the laryngeal aspect of the epiglottis. These are the parts that become most congested and swollen in acute laryngitis ; and the serious condition known as cedema of the glottis depends mainly upon effusion into the lax submucous tissue in the aryteno-epiglottidean folds. The affection known as " clergyman's sore-throat " has an interesting anatomical basis. The mucous membrane of the larynx is well provided with mucous glands, whose function it is to keep moist the parts concerned in phonation. When an individual speaks aloud for a Chap. IX.] The Larynx and Trachea. 133 long while the lining of the larynx tends to become dry, on account of the large amount of cold air that is drawn in directly through the mouth. To still keep these parts moist the mucous glands have to exhibit increased energy, and in those who speak much in public the glands may in time become so over-worked as to inflame. It is the inflammation of these glands that constitutes the present aflection. The glands are not distributed equally over all parts of the larynx, but are most numerous in the membrane covering the arytenoid cartilages and parts immediately about them, the base of the epiglottis, and the interior of the ventricle. It is in these parts, therefore, that the changes in chronic glandular laryngitis, or dysphonia clericorum, are most marked. The entire larynx has been removed for carcino- matous disease, but the operation, although not imme- diately fatal, has not been followed by very satisfactory results. It is removed through an incision in the middle line, and has to be freed from those muscles that lie in front of it (sterno-hyoid, omo-hyoid), as well as from those that are attached to it (sterno-thyroid, thyro-hyoid, inferior constrictor and stylo-pharyngeus). The larynx is then separated from the trachea, and is dissected off from below up. The only vessels of any magnitude divided are the superior and inferior thyroid arteries and the thyroid veins. Both laryngeal nerves are cut. In separating the gullet and pharynx there is great risk of " button - holing " the former tube. Traclieotomy and laryngotomy. — The trachea is about four and a half inches in length, and from three-quarters to one inch in its extreme width. It is surrounded by an atmosphere of very lax con- nective tissue, which allows a considerable degree of mobility to the tube. The mobility of the trachea is greater in children than in adults, and 134 Surgical Applied Anatomy. [Chap. ix. adds much, to the difficulties of tracheotomy. In this procedure the windpipe is opened in the middle line by cutting two or three of its rings above, below_, or through the isthmus of the thyroid gland. Since the trachea, as it descends, lies farther from the surface, and comes in relation with more and more important structures, it is obvious that, other things being equal, the higher in the neck the operation can be done the better. The length of trachea in the neck is not so considerable as may at first appear, and, according to Holden, not more than some 7 or 8 of the tracheal rings (which number 16 to 20 in all) are usually to be found above the sternum. The distance between the cricoid cartilage and the sternal notch varies greatly, and depends upon the length of the neck, the age of the patient, and the position of the head. If 2 inches of trachea are exposed above the sternum when the head rests easily upon the spine, then in full extension of the head some f of an inch more of the windpipe will, as it were, be drawn up into the neck. According to Tillaux, the average full distance between the cricoid cartilage and the sternum is, in the adult, about 2| inches (7 cm.). The full distance in a child between three and five years is about \\ inches (4 cm.), in a child between six and seven about 2 inches (5 cm.), and in children between eight and ten years about 2;| inches (6 cm.). As may be imagined, the dimensions of the trachea on section vary greatly at different ages, and even in different individuals of the same asje. This leads to the question as to the proper diameter of tracheotomy tubes. Guersant, who has paid much attention to this matter, says that the diameter of the tubes should run from 6 mm. to 15 mm.* The tubes with a diameter of from 12 mm. to 15 mm. are for adults. * The reader may be reminded that 12 mm. = about half an inch, and 6 mm., therefore, = about a quarter of an inch. Chap. IX.] The Larynx and Trachea. 135 The tubes below 12 mm. are for children, and are divided into four sets. '"■•'■{tete'/or} S^-llMl'S'^o^m} U to i years of age. No. 2. „ 8 mm. „ 4 to 8 „ No. 3. „ 10 mm, „ 8 to 12 No. 4. „ 12 mm. „ 12 to 15 In children under eighteen njonths the diameter of the tube should be about 4 mm. In performing tracheotomy it is most impor- tant that the head be thrown as far back as possible, and that the chest be kept strictly in a line with the sternal notch, so that the relations of the middle line of the neck be preserved. Full extension of the head not only gives the surgeon increased room for the operation, but also brings the trachea nearer to the surface, and by stretching the tube renders it much less mobile. In cutting down upon the trachea in the middle line of the neck from the cricoid cartilage to the sternum the following parts are met with. Beneath the integument lie the anterior jugular veins. As a rule these veins lie some little way apart on either side of the median line, and do not communicate except by a large transverse branch which lies in the interfascial space at the upper border of the sternum. Sometimes there are many communicating branches right in front of the tracheotomy district, or the veins may form almost a plexus in front of the trachea, or there may be a single vein which will follow the middle line. Then comes the cervical fascia, enclosing the stemo-hyoid and sterno-thyroid muscles. The gap between the muscles of opposite sides is lozenge- shaped, and is such that the trachea can be exposed without dividing muscle fibres. The isthmus of the thyroid usually crosses the 2nd, 3rd, and 4th rings of the trachea. Above it a transverse communicating o 6 Surgical Applied Anatomy. [Chap. ix. branch between the superior thyroid veins is sometimes found. Over the isthmus is a venous plexus, from which the inferior thyroid veins arise, while below the isthmus these veins lie in front of the trachea together with the thyroidea ima artery (when it exists). The inferior thyroid vein may be represented by a single trunk occupying the middle line. In the infant before the age of two years the thymus extends up for a variable distance in front of the trachea. At the very root of the neck the trachea is crossed by the innominate and left carotid arteries and by the left in- nominate vein ; and lastly, abnormal branches of the superior thyroid artery may cross the upper rings of the windpipe.* The evil of wounding the thyroid isthmus is greatly exaggerated. I have frequently divided this structure in performing tracheotomy without any in- convenience resulting. Like other median raphe, the middle line of the thyroid isthmus has but a slight vascularity, and it has been shown that one side of the thyroid gland cannot be injected from the other (-i.e., by injection that would cross the isthmus). The difficulty of tracheotomy in infants depends upon the shortness of the neck, the amount of the subcutaneous fat, the depth at which the trachea lies, its small size, its great mobility, and the ease with which it can be made to collapse on pressure. To the finger, roughly introduced, the infant's trachea offers little resistance. Its mobility is such that we hear of its being held aside unknowingly by retractors, while the operator is scoring the oesophagus (Durham). In the child also the great vessels often cross the trachea higher up than in the adult, and some inconvenience may also arise from an unduly prominent thymus. In introducing * See an excellent article on the anatomy of this region by Dr. Pilcher, "Annals of Anatomy and Surgery." New York, April, 1881. Chap. IX.] The Larynx and Trachea. 137 the cannula, if the tracheal wound be missed, it is easy to thrust the instrument into the lax tissue be- neath the cervical fascia and imagine that it is within the windpipe. In laiyngotomy the air passage is opened by a trans- verse cut through the crico-thyroid membrane. The crico-thyroid space only measures about half an inch in vertical height in well-developed adult subjects, while in children it is much too small to allow of a cannula being introduced. The crico-thyroid arteries cross the space, and can hardly escape division. They are, as a rule, of very insigniticant size, and give no trouble. Occasionally, however, these vessels are large, and " cases are recorded in which serious and even fatal haemorrhage has occurred from these vessels " (Durham). In introducing the cannula it may readily slip between the crico-thyroid membrane and the mucous lining instead of entering the trachea. Foreigrii bodies often tind their way into the air passages, and have been represented by articles of food, teeth, pills, buttons, small stones, and the like. They are usually inspired during the act of respiration, and may lodge in the superior aperture of the larynx, or in the rima, or find their way into the ventricle, or lodge in the trachea, or enter a bronchus. If a foreign substance enters a bronchus it usually selects the right, that bronchus having its aperture more im- mediately under the centre of the trachea than has the left tube. Quite recently, in a dissecting-room subject, I found two threepenny pieces lying side by side, in the right bronchus, so as to entirely block the tube. The danger of inhaled foreiijn substances de- pends not so much upon the mechanical obstruction they offer, as upon the spasm of the glottis they excite by reflex initation. A body may, however, lodge in the ventricle for some time without causing much trouble, as in a case reported by Desault, where a cherry-stone 138 Surgical Applied Anatomy. [Chap. ix. lodged for two years in this cavity without much inconvenience to its host. In one strange case a bronchial gland found its way into the trachea by producing ulceration of that tube, was coughed up, and became impacted in the rima glottidis. The patient was saved from immediate suffocation by tracheotomy. The ttiyroid body. — Each lobe should measure about 2 inches in length, about 1| inches in breadth, and 1^ of an inch in thickness at its largest part. When distinctly beyond these measurements the thyroid may be considered to be enlarged. Its usual weight is between one and two ounces. It is larger in females than in males, and the right lobe is usually larger than the left. In connection with these matters it may be noted that thyroid enlargements (broncho- cele, goitre) are more common in females than in males, and in any case are more apt to be first noticed on the right side. The body being closely adherent to the trachea and larynx, it follows that it moves up and down during deglutition, and this circum- stance is of the utmost value in the diagnosis of bronchocele from other cervical tumours. The thyroid when enlarged may distort and narrow the trachea, and this is all the more likely to be the case when the enlargement occurs rapidly, since the body is held down by the sterno-hyoid, sterno-thyroid, and omo- hyoid muscles. In some cases, therefore, of dyspnoea produced by rapidly growing bronchoceles, Bonnet has proposed subcutaneous section of these muscles. Since the isthmus must bind together the enlarging lobes of a bronchocele, Sir Duncan Gibb, on the other hand, proposed to divide the isthmus in cases where dyspnoea resulted. This operation he performed several times with great relief to the patient. The thyroid body is very vascular, and is invested by a thin capsule. In removing the gland (and many Chap, ix.i The Gullet 139 enlarged thyroids have been successfully removed entire), great care should be taken not to tear through this capsule before the vessels are secured. If the capsule be torn, the gland tissue is ex- posed and is apt to bleed profusely. Since the superior thyroid arteries enter at the upper end of each lobe, and the inferior thyroid vessels at the lower end, it is essential, before the actual removal of the mass is commenced, that the vessels be secured en. masse at each of the four corners of the body. The posterior border of the thyroid body being in contact with the sheath of the great vessels, it follows that the gland when enlarged may readily receive pulsations from those vessels. It generally touches also the lower part of the pharynx, and the upper part of the gullet behind, and enlargement in this direction may, in con- nection with the interference with the movement of the larynx in deglutition, serve to explain the difficulty in swallowing often noticed in bronchocele. The sriillet commences opposite the sixth cervical vertebra, and pierces the diaphragm opposite the tenth or eleventh dorsal. It presents three curves : one is antero- posterior, and corresponds to the curve of the spinal column ; the other two are lateral. The gullet commencing at the middle line deviates slightly to the left as far as the root of the neck ; from thence, to the fifth dorsal vertebra, it gradually returns to the middle line, and finally it turns again to the left, at the same time passing forwards, to pierce the diaphragm. Its length is from 9 to 10 inches. Its transverse diameter has been carefully estimated by Dr. Mouton, by filling the gullet with plaster of Paris in situ, and then measuring the cast thus obtained. Dr. Mouton found that there were three narrow parts in the gullet, one at its com- mencement, one about 2| inches from that point, and a third where the tube passed through the diaphragm. 140 Surgical Applied Anatomy. [Chap. ix. The diameter at eacli of these points was a little over half an inch (14 mm.); the diameter elsewhere was about \ inch (17 mm. to 21 mm,). By for- cible distension the two njDj^er narrow parts could be distended to a diameter of 18 to 19 mm,, the lower part to 25 mm,, and the rest of the gullet to a diameter of nearly 1| inches (35 mm.). It follows that foreign bodies when swallowed are most apt to lodge either at the commencement of the gullet or at the spot where it passes the diaphragm. The same parts also are those most apt to show the effects of corrosives that have beeii swallowed. Among the relations of the oesophagus, the follow- ing may be noted as receiving illustration in surgical practice. The gullet is in nearly all its course in close relation with the front of the vertebral column. In the neck the trachea is immediately in front of it. In the thorax it is in close connection with the aorta, and has the vena agygos behind it and on its right- hand side. It is, moreover, partly in contact with both pleurae, but more especially with the membrane of the right side; and, lastly, the recurrent laryngeal nerve ascends between it and the trachea. {See Figs. 33 and 35,) ISTow, foreign bodies impacted in the gullet are very apt to lead to ulcerations that may open adjacent parts. Thus, in the Musee Dupuytren is a specimen showing a five-franc piece that had stuck in the gullet, and had produced an ulcer that had opened the aorta. In another instance a "smasher" swallowed a counterfeit half-crown piece. Eight months after he died of ha}morrliage. The coin had sloughed into his aorta. In another case {Lancet^ 1871), a fish-bone, lodged in the gullet opposite the fourth dorsal vertebra, had caused two perforating ulcers ; one on the right side had caused plugging of the vena azygos major, while the other on the left had made a hole in the aorta. Chap. IX.] The Gullet. 141 Less frequently impacted foreign substances have found their way into the trachea and into the posterior mediastinum. Dr. Ogle reports a case (Path. Sec. Trans., vol. iv.) where a piece of bone impacted in the gullet induced ulceration of an intervertebral disc and subsequent disease of the spinal cord. Carcinoma of the gullet, also, when it spreads, is apt to invade adjacent parts, and especially to open into the trachea or bronchi. If it spreads to the pleura, it will usully involve the right pleura, as being the membrane more in relation with the gullet. Cancer of the gullet has so spread as to invade the thyroid body, the pericardium, and the lung, and has opened up the first intercostal artery in one case, and the right subclavian in another (Butlin's "Sarcoma and Carcinoma," 1882). The operation of oesopliagotomy consists in incising the gullet for the purpose of removing an impacted foreign body. The gullet is usually reached from the left side, since it projects more on that aspect. The incision is made between the sterno- mastoid and the trachea, in the same direction as the incision for ligaturing the common carotid. The cut extends from the top of the thyroid cartilage to the sterno-clavicular joint. The omo-hyoid muscle is drawn outwards, or cut. The great vessels, larynx and thyroid gland, are drawn aside, and care must be taken not to wound these structures nor damage the thyroid vessels or the recurrent nerve. The gullet, when exposed, is opened by a vertical incision. In opsophagostomy the opening is made into the omllet throucjh a like incision in cases of stricture of the tube high up, the object being to feed the patient through the opening made, in place of per- forming gastrostomy. The risk, however, of setting up severe diffuse inflammation in the loose planes of connective tissue deep in the neck is very great, and 142 Surgical Applied Anatomy. [Chap. ix. in some twenty-six cases in whicli the operation has been akeady performed death has, in nearly all instances, supervened at the end of a few hours or days. Oreat vessels. — The course, relations^ and ab- normalities of the great cervical vessels, together with the operations whereby they may be ligatured, and the details pertaining to those procedures, are so fully given, not only in works on operative surgery, but also in the chief anatomical text-books, that nothing need be said upon the matter in this place. The bifurcation of the common carotid is a favourite locality for aneurism, being a point where some resis- tance is offered to the blood current. These tumours, also, are common at the root of the neck, where they are often due to extension of aneurismal disease from the aorta, although in many cases they have an in- dependent origin. It is in the neck that the treat- ment of aneurism by the distal ligature is most often carried out. There is no place in the body where Brasdor's operation can be carried out with the completeness with which it can be adopted in the neck. In this procedure, a main trunk is ligatured on the distal side of an aneurism, no branches inter- vening between the sac and the ligature. The cure by this measure depends upon the fact that blood does not continue to go to parts when once the need for blood in them is diminished. Thus, after amputation at the hip joint, the femoral artery, having no need to carry to the stump the amount of blood it brought to the limb, often shrinks to a vessel no larger than the radial. When an aneurism low down in the carotid artery is treated by ligature of the vessel near its bifurcation by Brasdor's method, the blood, having now, as it were, no object in entering the carotid trunk, soon ceases to fill the vessel entirely, and the artery (and in successful cases the aneurism) Chap. IX.] The Neck. 143 shrinks in consequence. Wardrop's operation, or the distal ligature of large branches for the relief of aneurism of a main trunk, is now, perhaps, quite limited as to its performance to the ligature of the carotid and subclavian arteries for innominate aneur- ism. Since in this procedure large branches come ofi between the sac and the ligature, it is not easy to fully understand how the operation acts beneficially. It is assumed to owe its success to the same principle that underlies Brasdor's operation. The right carotid and subclavian have also been ligatured for aortic aneurism with some success, and here also the reason for the good effected by the operation is difficult to appreciate. It has been pointed out that the innominate artery lies more or less directly in the axis of the ascending aorta, while the left carotid and subclavian arteries arise at an angle to that axis, and it is upon this fact that reasons have been founded for selecting the vessels of the right side (Barwell). The matter is, however, complicated by the knowledge that when vegetations are swept off the aortic valves they enter the left carotid \%T.th infinitely greater frequency than they do the right. The whole subject, indeed, requires investigation. The cervical connective tissue being lax, aneurisms in this part can grow and spread rapidly, and usually soon produce " pressure symptoms." As examples of these may be noted oedema and lividity of the face or the upper limb from pressure upon the main veins laryngeal symptoms from pressure upon the recurrent nerve or trachea, spasm of the diaphragm from pres- sure upon the phrenic nerve, damage to the sympa- thetic, and giddiness and impaired vision from anaemia of the brain. It must be remembered that the veins of the neck are under the influence of tlie respira- tory movements, and that when one of these vessels is opened air may very readily be drawn into it by 144 Surgical Applied Anatomy. [Chap. ix. the inspirator J act, just as air is drawn into the trachea. The vertebral artery has been ligatured with some benefit in cases of epilepsy. The artery is reached through an incision made along the posterior border of the sterno-mastoid muscle just above the clavicle. The "carotid tubercle" {see page 119) is then sought for, and vertically below it the artery lies in the gap between the scalenus anticus and longus colli muscles. The procedure is surrounded by considerable diffi- culties. Dr. Bright and Dr. Eamskill have stated that disease involving the vertebral artery just before it enters the skull may lead to pain at the back of the head. It is well known that the sub-occipital nerve lies in close connection with the artery over the posterior arch of the atlas, and that it gives a branch to the great occipital nerve which is distributed to the back of the head. The close connection of artery and nerve and this communicating branch may serve to explain the symptom noted. In some of Dr. Ram- skill's cases there was difficulty of articulation. This he ascribes to pressure upon the hypoglossal nerve, which is also in close relation with the vertebral ai-tery. The lympliatic g^lands in the neck are very numerous, and are arranged in the following sets: (1) Submaxillary (10 to 15), situate along the base of the jaw beneath the cervical fascia ; (2) supra- hyoid (1 or 2), situate about the middle line of the neck between the chin and the hyoid bone ; (3) super- ficial cervical (4 to 6), situate along the external jugTilar vein beneath the platysma ; (4) deep cervical, upper set (10 to 20), situate about the bifurcation of common carotid, and along the upper part of the in- ternal jugular vein ; (5) deep cervical^ lower set (10 to 16), situate about the lower part of the internal Chap. IX.] The Neck. 145 jugular vein, extending outwards into the supra- clavicular fossa, and becoming continuous with the axillary and mediastinal glands. These glands are very often enlarged and inflamed, and it is in this part of the lymphatic system that the changes in scrofula are most commonly met with. The inflammatory afTections in glands would appear to be always of a secondary nature (if we exclude some cases of inflammation excited by injury, and perhaps by exposure to severe cold), and to follow disturbances in those parts of the periphery whence they respectively receive their lymph. It may be convenient, therefore, to groujD the relations of certain glands to certain parts of the periphery. Scalp. — Posterior part = suboccipital and mas- toid glands. Frontal and parietal portions = parotid glands. Vessels from the scalp also enter the superficial cervical set of glands. Skin of face and neck = submaxillary, parotid, and superficial cervical glands. External ear = superficial cervical glands. Lower lip = submaxillary and suprahyoid glands. Buccal cavity = submaxillary glands and deep cervical glands (upper set). Gums of lower jaw = suhmsLxillsiry glands. Tongue. — Anterior portion =:: suprahyoid and sub- maxillary glands. Posterior portion = deep cervical glands (upper set). Tonsils and jmlate — deep cervical glands (upper set). Pharynx. — Upper part = parotid and retro-pha- ryngeal glands. Lower part = deep cervical glands (upper set). Larynx, orbit, and roof of mouth = deep cervical glands (upper set). Nasal fosscB = retro-pharyngeal glands, deep cervical K 146 Surgical Applied Anatomy. [Chap. ix. glands (npper set). Some lymphatics from posterior part of the fosses enter the parotid glands. * Sraiicliial listiilae. — Certain congenital fistulse are sometimes met with in the neck, which are due to partial persistence of one of the branchial clefts. These clefts are placed in the foetus between the branchial arclies. The arches are usually described as five in number. The first lays the foundation for the lower jaw. From the second are developed the incus, the styloid process, the stylo-hyoid ligament and lesser cornu of the hyoid bone. From the third is formed the body and greater cornu of the hyoid bone, while the fourth and fifth take part in the formation of the soft parts of the neck below the hyoid bone. The first cleft is between the first and second arches. " The cervical branchial fistulse appear congenitally as very fine canals opening into minute orifices in one or both sides of the fore part of the neck, and leading backwards and inwards or backwards and u})wards towards the pharynx or oesophagus " (Paget). Their length is about \\ to 21 inches, and their diameter varies from that of a bristle to that of an ordinary probe. They usually exist about the line of the third or fourth cleft, and are most often met with just above the sterno-clavicular joint. Others are found about the level of the top of the thyroid cartilage at the anterior edge of the sterno-mastoid muscle. It would appear that certain polycystic congenital tumours, occurring as one form of " hydrocele of the neck," may be de- veloped from an imperfectly closed cleft. I have elsewhere detailed the dissection of one of these tumours that appeared to be associated with a partially closed second branchial cleft (Path. Soc. Trans., 1881). * From " Scrofula, and its Gland Diseases," by the Author, 147 i3art ih CHAPTER X. THE THORAX. 1. The thoracic Avails. — The two sides of the chest are seldom symmetrical, the circumference of the right side being usually the greater, a fact that is supposed to be explained by the unequal use of the upper limbs. In Pott's disease, involving the dorsal region, when the spine is much bent forwards, the thorax becomes greatly deformed. Its antero-posterior diameter is increased, the sternum protrudes, and may even be bent by the bending of the s])ine, the ribs are crushed together, and the body may be so shortened that the lower ribs overlap the iliac crest. In pigeoo-breast deformity the sternum and cartilages are rendered protuberant, so that the antero- posterior measurement of the chest is much increased, while a deep sulcus exists on either side along the line of junction of the ribs and their cartilages. It is by the sinking in of the parietes along this line that the protuberance is produced. Shaw gives the following explanation of this deformity : " AVhen an inspira- tion is taken, a threatened vacuum is created within the chest, air rushes in by atmospheric pressure, and at the end of the inspiration the balance of pressure without the chest and within it are equalised. If in inspiration there is an impediment to the entrance of air, the atmospheric pressure upon the external wall of the chest must produce some effect, being un- balanced by a like pressure upon the inner chest wall. In children, and especially in rickety childi'en, the 148 Surgical Applied Anatomy. [Chap. x. thorax is very pliable and elastic, and if a constant impediment exists to the entrance of air, as afforded, for example, by greatly enlarged tonsils, the thoracic walls may yield in time to the unbalanced pressure brought to bear upon them at each inspiration. The weakest part of the thorax is along the costo-chondral line on either side, and it is here that the parietes yield most conspicuously in such cases, and by this yielding the deformity is produced." The sternum. — The upper edge of the sternum Cin inspiration) corresponds to the disc between the second and third dorsal vertebrae, and the sterno- xiphoid joint to the lower part of the ninth dorsal. A transverse ridge may be felt upon its anterior sur- face that corresponds to the junction of the manu- brium and gladiolus, and is in a line with the second costal cartilages. The skin over the sternal region is the part of the surface most frequently the seat of keloid. The bone is rarely fractured, being soft and spongy, and supported by the elastic . ribs and their cartilages, as by a series of springs. In the old, when the cartilages are ossified and the chest more rigid, the tendency to fracture is increased. The sternum is most often found fractured in connec- tion with injuries to the spine, although it may be broken by simple direct violence. The bone may be fractured by violent bending of the spine backwards, and by abrupt bending of it forwards. In the former instance the lesion is probably due to muscular violence, to the abdominal muscles and the sterno- mastoid pulling one against the other. In the latter instance the lesion is commonly brought about by the violent contact of the chin with the bone. In all instances the fracture is usually transverse, and most often occupies the line between the manubrium and the gladiolus. As these two parts of the bone are not entirely united until middle life, and are often Chap. X.] The Thorax. 149 not united at all, it follows that the lesion is in many- cases a dislocation rather than a fracture. The manu- brium in these injuries generally remains in situ, while the gladiolus with the ribs is displaced forwards in front of it. Malgaigne cites the case of a youth who, from constant bending at his work as a watch- maker, caused the second piece of the sternum to glide backwards behind the manubrium. Here, prob- ably, the connection between the two bones was not very substantial. From its exjwsed position and cancellous structure, the sternum is liable to many affections, such as caries and gummatous periostitis. The comparative softness also of the bone is such that it has been penetrated by a knife in homicidal wounds. The shape and position of the bone have also been altered by pressure, as seen sometimes in artisans following employments re- quiring instruments, etc., to be pressed against the chest. Certain holes may appear in the middle of the sternum, and through them mediastinal abscesses may escape, and surface abscess pass deeply into the thorax. In the case of E. Groux, the bone was separated verti- cally into two parts. The gap could be opened by muscular effort, and the heart exposed covered only by the soft parts. The sternum has been trephined for mediastinal abscess, and for paracentesis in peri- cardial effusion, and it has been proposed also to ligature the innominate artery through a trephine hole in the upper part of the bone. The ribs are placed so obliquely that the anterior end of one rib is on a level with the posterior end of ] a rib some way below it in numerical order. Thus * the first rib in front corresponds to the fourth rib behind, the second to the sixth, the third to the seventh, the fourth to the eighth, the fifth to the ninth, the sixth to the tenth, and the seventh to the eleventh. 15c Surgical Applied Anatomy. [Chap. x. If a horizontal line be drawn round the body at the level of the inferior angle of the scapula, while the arms are at the side, the line would cut the sternum in front between the attachments of the fourth and fifth ribs, would cut the fifth rib at the nipple line, and the ninth rib at the vertebral column. The second rib is indicated by the transverse ridge on the sternum already alluded to. The lower border of the pectoralis major leads to the fifth rib, and the first visible serration of the serratus magnus corresponds to the sixth. The longest rib is the seventh, the shortest the first. In breadth the bones decrease from the first to the twelfth. The most oblique rib is the ninth. The ribs are elastic and much curved, and being attached by many ligaments behind to the column, and in front to the yielding cartilages, resist injuries tending to produce fracture with the qualities possessed by a spring. A rib may be fractured by indirect violence, as by a wheel passing over the body when lying prostrate on the back. In such a case the force tends to approximate the two ends of the bone, and to increase its curve. When it breaks, therefore, it breaks at the summit of its principal curve, i.e., about the centre of the bone. The fragments fracture outwards, and the pleura stands no risk of being penetrated. When the rib is broken by direct violence, the lesion occurs at the spot encountered by the force, the bone fractures inwards, the curve of the rib tends to be diminished rather than increased, and there is much risk of the fragments lacerating the pleura. Those most often broken are the sixth, seventh, and eighth, they being under ordinary circumstances the most exposed. The rib least frequently fractured is the first, which lies under cover of the clavicle. Fractures are more common in the elderly than in children, owing to the ossification of the cartilages Chap, x.i The Thorax. 151 that takes place in advancing life. When a rib is fractured, no shortening occurs, the bone being fixed both in front and behind, while vertical displacement is prevented by the attachments of the intercostal muscles. Thus no obvious deformity is produced unless a number of consecutive ribs are the subjects of frac- ture. These bones have been broken by muscular violence, as during coughing, and in violent expulsive efforts such as are incident to labour. In such in- stances the ribs are probably weakened by atrophy or disease. In many instances of gun-shot wound the curve of the rib has saved the patient's life. In such cases the bullet has entered behind near the dorsal spine, has been conducted round the chest, along the curve of a rib beneath the skin, and has escaped again near the sternum. This property, however, of the ribs for turning bullets refers rather to the days of round bullets, and not to modern conical projectiles. In rickets changes take j^lace at the point of junction of the ribs and cartilages leading to bony elevations, which produce, when the ribs on both sides are affected, the condition known as the " rickety rosary." The intercostal spaces are wider in front than behind, and between the upper than the lower ribs. The widest of the spaces is the third, then the second, then the first. The narrowest spaces are the last four. The first five spaces are wide enough to admit the whole breadth of the index fins^er. The spaces are widened in inspiration, narrowed in expira- tion, and can be increased in width by bending the body over to the opposite side. Paracentesis is usually performed in the sixth or seventh space, at a point midway between the sternum and the spine, or midway between the anterior and posterior axillary lines. If a lower 152 Surgical Applied Anatomy. [Chap. x. space be selected there is great danger of wounding tlie diaphragm, especially upon the right side. The trochar should be entered during inspiration, the space being widened thereby, and should be kept as near as possible to the lower border of the space, so as to avoid the intercostal vessels. Tapping of the chest through any space posterior to the angles of the ribs is not practicable, owing to the thick covering of muscles upon the thoracic wall in this place, and the fact that the intercostal artery, having a more horizontal course than the corresponding ribs, crosses the middle of this part of the space obliquely. Beyond the angle the intercostal vessels lie in a groove on the inferior border of the rib forming the upper boundary of the space. The vein lies immediately above the artery, and the nerve immediately below it. In the upper four or five spaces, however, the nerve is at first higher than the artery. Giving to the protection it derives from the ribs and the intercostal muscles, it happens that the inter- costal artery is seldom wounded, and when wounded it will be understood that considerable difficulty is experienced in securing the vessel without doing damage to the pleura and adjacent parts. Pus may readily be conducted along the loose tissue between the two layers of intercostal muscles. Thus, in suppuration following upon disease of the transverse processes or bodies of the vertebrae, or of the posterior parts of the ribs, the pus may be conducted along the intercostal spaces to the sternum, and may thus present at a considerable distance from the real seat o*f the disease. The internal mammary artery runs parallel to the border of the sternum, and about half an inch from it. It may give rise to rapidly fatal haemorrhage if wounded. The vessel may readily be secured in the first three intercostal spaces, and with some difficulty Chap. X.] The Thorax. 153 in the fourth or fifth space. It is most easily reached througli the second space, and cannot be secured through any space below the fifth. The female breast extends from the third to the fifth rib. It is supported by the superficial pectoral fascia, which divides into two layers to enclose it. The organ is made up of an accumulation of racemose glands, which open into ducts discharging at the nipple. In cases where during lactation the acini are engorged with milk, the outlines of the several lobules and lobes of the breast are rendered very distinct. The size of the breast depends usually rather upon a deposit of fat collected about the organ and distributed among its lobules than upon a development of true gland tissue. A considerable and rapid development of the mammary gland tissue takes place at puberty, and the breast remains in its most perfect anatomical condition during the child- bearing period of life. After the cessation of men- struation, the glandular tissue atrophies, although the ducts always persist. The breast is thinner at the periphery than at the centre, and is thinnest about a line extending from the nipple to the sterno-clavicular joint. Abscesses situated beneath the breast not un- frequently make their way through the gland at some point along this line. The base of the gland is flat, and is separated from the pectoral muscle by much loose connective tissue. It is in this tissue that the sub- mammary abscess forms. There is sometimes a kind of bursa between the breast and the muscle which has been found to form a definite hygroma or bursal cyst (Velpeau). Although the gland is but loosely con- nected with the pectoralis major, yet it moves a little with that muscle, and the position of the breast can be slightly afiected by the movement of the arm. It is imjjortant, therefore, that the arm should be kept at rest in inflammatory afiections of the oi'gan. 154 Surgical Applied Anatomy. [Chap. x. In cancer, the gland and the muscle may become intimately adherent. The nipple is situated over the fourth interspace, about three-quarters of an inch from the junction of the ribs with their cartilages, and some four inches from the middle line. It contains muscular fibres, by means of which it can be rendered prominent on stimulation. The skin about the nipple is very thin and sensitive, and is often the seat of painful fissures and excoriations. When any contracting growth, such as scirrhus, drags upon the ducts of the gland, the nipple becomes retracted. Abscesses of the breast should be opened by in- cisions radiating from the nipple, so as to avoid un- necessary damage to the mammary ducts. The breast is supplied by the anterior cutaneous branches of the second, third, fourth, and fifth inter- costal nerves, and by the lateral branches of the last three of those nerves. The connections of these trunks serve to explain the difiusion of the pain that is sometimes observed in painful afiections of the gland. Thus iii abscess of the breast pain is often felt round the side of the thorax to the back, foUowinfi: the trunks of the above-named intercostal nerves; or it is distributed over the scapula by the cutaneous branches of the posterior divisions of such dorsal nerves as correspond to the intercostal trunks that supply the breast ; or it runs down the arm along the intercosto-humeral nerve (a branch of the second intercostal), or shoots up the neck, probably, along the supra-clavicular branch from the cervical plexus, which communicates with the same intercostal trunk. The gland is supplied by the following arteries, which are divided in excision of the organ : the second, third, fourth, and fifth intercostal branches of the internal mammary artery, some few branches from the corresponding intercostal vessels, the long Chap. X.1 The Thorax, 155 thoKicic artery, and the external mammary. The majority of the lymphatics from the breast proceed to the axilla. Some few follow the mammary branches of the internal mammary artery, and enter the anterior mediastinal glands, which are consequently often found enlarged in cancer of the organ. As the chief blood- supply of the breast comes from the axilla, and as the main lymph vessels pro- ceed to that region, it follows that malignant growths of the gland tend to spread towards the axilla rather than towards the middle line. 2. The thoracic i-iscera. The lung. — The apex of the lung rises in the neck fi'om one to one and a half inches above the clavicle. The anterior ed^fes of the two lunfjs lie behind the sterno-clavicular articulations, pass obliquely behind the manubrium, and meet in the middle line at the junction of the manubrium with the gladiolus. The edge of the right lung then continues vertically down- wards behind the middle line of the sternum to the sixth chondro-sternal articulation, where it slopes ofi' along the line of the sixth rib. The edge of the left lung keeps close to that of the right as far as the fourth chondro-sternal articulation, where it turns off to the left, following a line drawn from the fourth cartilage to the apex of the heart. The lower border of the lung corresponds to a slightly convex line drawn round the chest from the sixth chondro-sternal articulation in front to the tenth dorsal spine behind. In the mammary line this line would correspond to the sixth rib, opposite the posterior fold of the axilla with the eighth rib, and in a line continued vertically down- wards from the inferior angle of the scapula with the tenth rib. The pleura extends further down than the lung, reaching in front to the level of the seventh chondro-sternal union, behind to the eleventh dorsal spine, and at the sides to a point some two and a half 156 Surgical Applied Anatomy. [Chap. x. inches above the lower margin of the thorax. Thus it will be seen that the pleura and diaphragm may be wounded in many places without the lungs being involved. In penetrating wounds involving the pleura, air may enter the pleural cavity, producing pneumo- thorax, and this air may be subsequently pressed by the respiratory movements into the subcutaneous tissues through the wound in the parietal pleura, and lead to surgical emphysema. The two layers of the pleura are so intimately in contact with one another in the normal thorax that it is questionable whether the parietal pleura can be wounded without injury to the visceral layer. In wounds of the lung without external wound, as when that organ is torn by a fractured rib, the air escapes from the lung into the pleura, and may thence pass into the subcutaneous tissues through the pleural wound, thus producing both pneumo-thorax and emphysema. It is well to note that emphysema may occur about certain non-penetrating wounds of the thorax when they are of a valvular nature. In such cases the air is drawn into the subcutaneous tissues during one respiratory movement, and is forced by another into the cellular tissue, the valvular nature of the wound preventing its escape externally. When the pleural " cavity " is opened, the lungs become more or less collapsed ; yet a few cases have been recorded where the lung has protruded at the time of the acci- dent through the wound in the parietes. In such in- stances the glottis must have been closed, and the lung fully distended at the time of the injury ; and it must be further assumed that the viscus was practically pro- truded before air could enter the pleural space. It is noticeable that these recent hernise are most common at the anterior part of the chest where the lungs are the most movable, and the injuries that bring them Chap, x.i The Thorax. 157 about are often associated with violent respiratory efforts at the time of the accident. In wounds of the king the blood may escape in three directions : into the tissue of the organ (pulmonary apoplexy), into the bronchi (causing haemoptysis), and into the pleura (causing hsemothorax). In some instances the lung has been ruptured without wound and without frac- ture of the ribs. These cases are difficult to interpret, and probably the best explanation suggested is that put forward by M. Gosselin. This surgeon believes that at the time of the injury the lungs are suddenly filled and distended with air by a full inspiration, and that the air, prevented from escaping by occlusion of the larynx, thus becomes pent up in the pulmonary tissue, and the lung not being able to recede from the superincumbent pressure, its structure necessarily gives way. Owing to the fineness of its capillaries, and to the fact that all venous blood returned to the heart must pass through the lungs before it can reach other parts of the body, it follows that pyaemic and other secondary deposits are more commonly met with in the lung than in any other of the viscera. The trachea divides opposite the junction of the manubrium and gladiolus in front, and the interval between the third and fourth dorsal spines behind (Fig. 33). Certain foreign substances that have been drawn into the air passages have shown a remarkable facility for escaping through the parietes. Thus Mr. Godlee records the case of a child, from an abscess in whose back a head of rye-grass escaped, that had found its way into the air passages forty-three days previously. The heart. — The relations of the heart to the surface are as follows. Its upper limit corresponds to a horizontal line crossing the sternum about the upper border of the third cartilages. Its right border 158 Surgical Applied Anatomy. [Chap. x. to a curved line arching from the third right cartilage at the sternum to the seventh right chondro-sternal articulation, and reaching about \^ inches from the middle line. Its lower border follows a line from the Fig. 16.— Diagram to show the relations of the Heart to the Surface. ( After Elidinger.) a. Left innominate vein ; 6, right innominate vein ; c, superior vena cava ; d, right auricle ; e, inferior vena cava ; /, aorta ; g, pulmonary artery ; h, right ven- tricle ; i, left ventricle ; j, left auricle. seventh right chondro-sternal articulation to the apex. Its apex is opposite the fifth interspace, 3-| inches to the left of the middle line. Its left border is repre- sented by an arched line drawn from the apex to the third left cartilage at the sternum. The orifice of the pulmonary artery is behind the 'Upper edge of the third left cartilage close to the Chap. X.] The Thorax. 159 sternum. The vessel proceeds upwards under cover of the second left cartilage. The aortic orifice is behind the left border of the sternum close to the lower edge of the third cartilage. The trunk ascends behind the second cartilage of the right side, and would be wounded by a stab through that cartilage close to the sternum. The concavity of the aortic arch corre- sponds to the point between the first and second pieces of the sternum. The auriculo-ventricular orifices are behind the sternum, the right being opposite the fourth spaces, and the left on a level with the fourth carti- lages. The innominate and left carotid arteries come oft' at a spot corresponding to the middle of the manu- brium, and run behind the right and left sterno-cla- vicular joints respectively. The superior vena cava would be wounded by a knife entering either the fii'st or the second right interspace close to the sternum. The left innominate vein lies transversely just below the upper border of that bone. The right auricle would be wounded in stabs passing through the sternal ends of the third, fourth, and fifth cartilages on the right side, or through the corresponding intercostal spaces if the knife be kept fairly near to the sternum. {See Fig. 16, which shows the relations of the heart and great vessels as given by Eiidinger, and which differ somewhat from the above account.) A circle with a diameter of two inches, and with its centre midway between the nipple and the end of the gladiolus, would approximately define that part of the heart which lies immediately behind the chest wall^ and is uncovered by lung or pleura (Latham). Wounds of the heart most frequently involve the right ventricle, that segment of the heart being the part most exposed anteriorly. Next in frequency is the left ventricle wounded, and then the right auricle. Other things being equal, a wound of the ventricle is i6o Surgical Applied Anatomy. [Chap. x. less rapidly fatal than is a wound of the auricle, owing to the thickness of the ventricular wall, and to its capacity for contracting and preventing the escape of blood. Death in cases of wound of the heart would appear in a great number of cases to be due to an impression upon the nervous centres rather than upon actual haemorrhage. Many instances have been recorded to show that the heart may be very tolerant of foreign bodies in its substance. Thus a man lived for twenty days with a skewer traversing the heart from side to side (Ferrus). In another case a lunatic pushed an iron rod, over six inches in length, into his chest, until it disappeared from view, although it could be felt beneath the skin receiving pulsation from the heart. He died a year following, and the metal was found to have pierced not only the lungs, but also the ventricular cavities (Tillaux). A profos of chest wounds, Yelpeau cites the case of a man in whose thorax was found a part of a foil that entirely transfixed the chest from ribs to spine, and that had been introduced fifteen years before death. In the museum of the Royal College of Surgeons is the shaft of a cart that had been forced through the ribs on the left side, had passed entirely through the chest, and had come out through the ribs on the right side. The patient had lived ten years. Paracentesis of the pericardium has been performed through the fourth or fifth spaces on the left side close to the sternum, care being taken to avoid the internal mammary artery. The operation has also been performed through a trephine hole made in the middle line of the sternum. The mediastiiBa. — Abscess in the anterior mediastinum may have developed in situ, or may have spread down from the neck. In like manner posterior mediastinal abscesses may arise from diseases of the adjacent spine, or lymphatic glands, or may be Chap. X.J The Thorax. i6i due to the spreading downwards of a retro-])haryngeal or retro-CESophageal collection of matter. The azygos veins, commencing as they do below in the lumbar veins, and having more or less direct communications with the common iliac, renal, and other tributaries to the vena cava, are able to a great extent to carry on the venous circulation in cases of obstruction of the main trunk. These veins are apt to be pressed upon by tumours (such as enlarged gland masses) developed in the posterior mediastinum, and to produce in consequence some oedema of the chest walls by engorgement of those intercostal veins that they receive. Tumours growing in the posterior mediastinum may cause trouble by pressing upon the trachea or gullet, or by disturbing the vagus nerve or the cord of the sym- [)athetic (Figs. 33 and 35). l62 part Mh The Upper Extremitf. CHAPTER XL the region of the shoulder. A STUDY of the region of the shoulder comprises the clavicle, the scapula, the upper end of the humerus, and the soft parts that surround them, together with the shoulder joint and axilla. Surface anatomy. — The clavicle, acromion pro- cess, and scapular spine are all subcutaneous, and can be readily felt. In the upright position, when the arm hangs by the side, the clavicle is, as a rule, not quite horizontal. In well-developed subjects it inclines a little upwards at its outer end.* In the recumbent j)osture, the weight of the limb being taken off, the outer end rises still higher above the sternal extremity. The degree of the elevation can be best estimated by a study of frozen sections. Thus, in making horizontal sections of the body, layer by layer, from above down- wards, Braune found that by the time the sterno- clavicular articulation was reached, the head of the liumerus would be cut across in the lateral part of the section (Fig. 17). The deltoid tubercle of the clavicle may, if large, be felt through the skin, and be mistaken for an exostosis. The acromio-clavicular joint lies in the plane of a vertical line passing up the middle of the * In some wonrion, in the feeble, and in some narrow-shoul- dered men, the clavicle may be horizontal, or its outer end may incline downwards. Chap. XI.] Region of the Shoulder. 163 front of the arm. A prominence is sometimes felt about this joint in place of the level surface that it should present. This is due to an enlargement of the end of the clavicle, or to a thickening of the fibro- cartilage sometimes found in the joint. In many cases it has appeared to me to be due to a trifling luxation upwards of the clavicle depending upon some stretching of the ligaments. It is certain that the dry bone seldom shows such an enlargement as to account for this very common prominence at the acromial articulation. The sternal end of the clavicle is also, in muscular subjects, often large and unduly prominent, and sufficiently conspicuous to suggest a lesion of the bone or joint when none exists. The roundness and prominence of the point of the shoulder depend upon the development of the deltoid and the position of the upper end of the humerus. The deltoid hangs like a curtain from the shoulder girdle, and is bulged out, as it were, by the bone that it covers. If the head of the humerus, there- fore, be diminished in bulk, as in some impacted fractures about the anatomical neck, or be removed from the glenoid cavity, as in dislocations, the deltoid becomes more or less flattened, and the acro- mion proportionately prominent. The part of the humerus felt beneath the deltoid is not the head, but the tuberosities, the greater tuberosity externally, the lesser in front. A considerable portion of the head of the bone can be felt by the fingers placed high up in the axilla, the arm being forcibly abducted so as to brins: the head in contact with the lower part of the capsule. The head of the humerus faces very much in the direction of the internal condyle. As this relation, of course, holds good in every position of the bone, it is of value in examining injuries about the shoulder, and in reducing disloca- tions by manipulation, the condyle being used as 164 Surgical Applied Anatomy. [Chap. xi. an index to the position of the upper end of the bone. In thin subjects the outline and bordei^s of the scapula can be more or less distinctly made out, but in fat and muscular subjects all parts of the bone, except the spine and acromion, are difficult of access in the ordinary positions of the limb. To bring out the superior angle and vertebral border of the bone, the hand of the subject should be carried as far as pos- sible over the opposite shoulder. To bring out the inferior angle and axillary border, the fore-arm should be placed behind the back. The angle formed at the point of junction of the spine of the scapula and the acromion, is the best point from which to take measurement of the arm, the tape being carried down to the external condyle of the humerus. When the arm hangs from the side with the palm of the hand directed forwards, the acromion, external condyle, and styloid process of the radius, all lie in the same line. The groove between the pectoralis major and deltoid muscles is usually to be made out; In it run the cephalic vein and a large branch of the ac. romio- thoracic artery. Near the groove, and a little below the clavicle, the coracoid process may be felt. The process, however, does not actually present in the interval between the two muscles, but is covered by the innermost fibres of the deltoid. The position of the coraco-acromial ligament may be defined, and a knife, thrust through the middle of itj should strike the biceps tendon and open the shoulder joint. When the arm hangs at the side with the palm forwards, the bicipital groove may possibly be defined. It looks directly forwards. Just below the clavicle is a depression, the sub- clavicular fossa, which varies considerably in depth in different subjects. It is obliterated in subcoracoid dislocations of the humerus, in fractures of tlie clavicle Chap. XI.] Region of the Shoulder. 165 with displacement, by many axillary growths, and by some inflammations of the upper part of the thoracic wall. In subclavicular, or intracoracoid dislocation, the fossa is replaced by an eminence. In this region, at a spot to the inner side of the coracoid process, and corresponding nearly to the middle of the clavicle, the pulsations of the axillary artery can be felt on deep pressure, and the vessel be compressed against the second rib. Just below the clavicle the interspace between the sternal and clavicular portions of the pectoralis major can often be made out. The anterior and posterior borders of the axilla are very distinct. The anterior border formed by the lower edge of the pectoralis major follows the line of the fifth rib. The depression of the armpit varies, other things being equal, with the position of the upper limb. It is most deep when the arm is raised from the side at about an angle of 45°, and when the muscles forming the borders of the space are in a state of contraction. As the arm is raised above the horizontal line the depression becomes shallower, the head of the bone projects into the space and more or less obliterates it, while the width of the fossa is encroached upon by the approximation of the anterior and posterior folds. The coraco-brachialis muscle itself forms a distinct projection along the humeral side of the axilla when the arm is raised to a right angle with the body. If the arm be brought nearly close to the side, the surgeon's hand can be thrust well up into the axilla, and the thoracic wall explored as high up as the third rib. The axillary glands cannot be felt when they are in a noiTual condition. The direction of the axillary artery, when the arm is i*aised from the side, is i-epresented by a line drawn from about the middle of the clavicle to the humerus at the inner side of the coraco-brachialis. A line 1 66 Surgical Applied Anatomy. [Chap. xi. drawn from the third rib near its cartilage to the tip of the coracoid process indicates the upper border of the pectoralis minor, and the spot where this line crosses the line of the axillary arterj points out the position of the acromio- thoracic artery. A line drawn from the fifth rib near its cartilage to the tip of the coracoid process indicates the lower border of the pectoralis minor, and the position of the long thoracic artery which runs along that border. The line of the subscapular artery corresponds to the lower border of the subscapularis muscle along which it runs, but the position of this border can only be approximately indicated on the living or undissected subject. The circumflex nerve and posterior circumflex artery cross the humerus in a horizontal line that is about a finger's breadth above the centre of the vertical axis of the deltoid muscle. This point is of importance in cases of supposed contusion of the nerve. The dorsalis scapulse artery crosses the axillary border of the scapula at a point corresponding to the centre of the vertical axis of the deltoid muscle. These various indications of the positions of the main branches of the axillary artery are made while the arm hangs in its natural position at the side. The clavicle. — The skin over the clavicle is loosely attached, and is easily displaced about the bone. This circumstance may serve to explain why the skin so often escapes actual wound in contusions of the clavicular region, and in part explains the infrequency of penetration of the integument in fractures of the clavicle. The position of the supra- clavicular nerves in front of the bone renders them very liable to contusion, and accounts for the unusual amount of pain that is said to sometimes follow blows over the collar bone. Tillaux believes that the severe pain that in rare cases persists after fracture of the clavicle is due to the implication of these nerves Chap. XL] The Clavicle, 167 in the callus formed. The three nerves that cross the clavicle are branches of the third and fourth cervical nerves, and it is well to note that pain over the collar bone is sometimes a marked feature in disease of the upper cervical spine. This symptom is then due to irritation of these nerves at their points of exit from the spinal canal. Beneath the clavicle the great vessels and the gi'eat nerve-cords lie upon the lirst rib. The vein is the most internal, and occupies the acute angle between the collar bone and the first rib. It will be seen that groAvths from the bone may readily press upon these important sti'uctures, and that the vein, from its position, as well as from the slighter resis- tance that it otFers, is likely to be the tirst to be compressed. These structures have also been wounded by fragments of bone in fracture of the clavicle. Fortu- nately, between the clavicle and these large nerves and vessels the subclavius muscle is interposed. This muscle is closely attached to the under surface of the bone, is enveloped in a dense fascia, and forms one of the chief protections to the vessels in cases of fracture. This interposing pad of muscle is also of great service in resection operations, as can be well understood. Braune states that by pressing the clavicle against the first rib in the dead body a stream of injection in the thoracic duct can, in some cases, be entirely arrested. Behind the clavicle the following structures may be noted : The brachio-cephalic, subclavian, and external jugular veins, the subclavian, suprascapular, and in- ternal mammary arteries, the cords of the brachial plexus, the phrenic nerve and nerve of Bell, the thoracic duct, the omo-hyoid, scalene, sterno-hyoid and sterno- thyroid muscles, the ap^x of the lung. The sternal end of the bone is not far removed from the innominate, or left carotid artery, the vagus and recurrent nerves, the trachea, and the oesophagus. i68 Surgical Applied Anatomy. [Chap. xi. These relations of the clavicle are given to show the dangers in the way of partial or complete resections of the bone. The difficulties and risks of the operation increase as one progresses from the k Is Fig, 17.— Horizontal Section of the Body just below the Upper Border of the Manubrium (BratJie). a. Manubrium ; b, head of humerus ; c, clavicle ; d, first rib : e, second rib ; /, third dorsal vertebra; 3, spine of second dorsal; h. pectoralis major; i, deltoid; J, infraspinatus ; k, subs'-apularis : I, coraco-brachialis and biceps ; m, pec- toralis minor ; w, sen-atus magnus ; 0, intercostals ; p, semispinalis and multifldus spinae ; q, biventer cervicis and complexus; r, longissimus dorsi ; s, splenius colli ; t, rhomTjoideus ; u, trapezius ; v, sterno-thyroid ; w, sterno- hyoid ; T, thymus ; l, lung ; 1, left innominate vein ; 2, left carotid artery ; 3, left subclavian artery : 4, vertebral artery ; 5, left subclavian vein ; 6, cephalic vein ; 7, phrenic nerve ; 8, vagus ; 9, transverse scapular artery. acromial to the sternal end. Resection of the acromial third of the bone is comparatively easy, but resection of the sternal portion is most difficult and dangerous. The entire clavicle has been removed with success, and the operation has been followed by less impair- ment of the arm movements than would be imagined. The clavicle forms the sole direct bony connection between the iipper limb and the trunk, and in severe Chap. XL] The Clavicle. 169 accidents, this connection being broken through, it is possible for the extremity to be torn off entire. Thus Billroth reports the case of a boy aged fourteen, whose right arm, with the scapula and clavicle, was so torn from the trunk by a machine accident, that it was only attached by a strip of skin two inches wide. Other like cases of avulsion of the limb have been reported. Fractures of clavicle. — The clavicle is more frequently broken than is any other single bone in the body. This frequency is explained by the fact that the bone is very superficial, is in a part exposed to injury, is slender and contains much compact tissue, is ossified at a very early period of life, and above all receives a large part of all shocks communi- cated to the upper extremity. The common fracture, that due to indirect violence, is oblique, and very constant in its position, viz., at the outer end of the middle third of the bone. ThvO bone breaks at this spot for the following reasons. It is here that the cla^acle is the most slender ; it is here that the two curves of the bone meet ; it is here that a very fixed part of the bone, viz., the outer third, joins with a more movable portion. The clisj^lacement that occurs is as follows. The inner fragment remains unchanged in position, or, its outer end is dra^\^l a little upwards by the sterno-mastoid. It will be seen that any action of this muscle would be resisted by the pectoralis major, and the rhomboid ligament. The outer fragment undergoes a threefold displace- ment. (1) It is carried directly doicnivards. This is effected mainly by the weight of the limb aided by the pectoralis minor, the lower fibres of the pectoralis major, and the latissimus dorsi. (2) It is carried directly imcards by the muscles that pass from the trunk to the shoulder, viz., the trapezius, the levator anguli scapulre, the rhomboids, the latissimus dorsi, and especially by the pectorals. To these may be added 1 70 Surgical Applied Aivatomv. [Chap. xi. the subclavius. (3) The fragment is rotated in such a way that the outer end projects forwards and the inner end back. This rotation is brought about mainly by the two pectorals assisted prominently by the serratus magnus. The normal action of this lattei" muscle is to carry the scapula forwards, and the clavicle, acting as a kind of outrigger to keep the upper limb at a proper distance from the trunk, moves forwards at the same time and keeps the scapula direct. When this outrigger is broken the serratus can no longer carry the scapula directly forwards. The bone tends to turn towards the trunk, and the point of the shoulder is therefore seen to move inwards as well as forwards. The fragments in this fracture must consequently overlap, and as the displacement is difficult to remedy, it follows that in no bone save the femur is shortening so uniformly left as after an oblique fracture of the clavicle. The degree of shortening very seldom exceeds one inch. The deformity associated with this fracture is well remedied when the patient assumes the recumbent position. In this posture, the weight of the limb being taken oft', the downward displacement is at once remedied. The point of the shoulder falling back also tends to relieve in part the inward displace- ment, and the rotation of the outer fragment forwards. It is through the scapula, however, that these two latter displacements are in the main removed. In the recumbent posture the scapula is pressed closely against the thorax, with the result that its outer extremity (and with it, of course, the outer fragment of the clavicle) is dragged outwards and backwards. Some surgeons,^ recognising this important action of the scapula in remedying the displacement in these cases; strap the scapula firmly against the trunk, while at the same time they elevate the arm. Fractures due to direct violence are usually Chap. XL] The Clavicle. 171 transverse, and may be at any part of the bone. When about the middle third they present Ww, displacement just described. When the fracture is between the conoid and trapezoid ligaments no dis- placement is possible. When beyond these ligaments the outer end of the outer fragment is carried forwards by the pectorals and serratus, and its inner end is a little drawn up by the trapezius. In this fracture there is no general displacement downwards of the outer fragment, since it cannot move in that direction unless the scapula go with it, and the scapula remains fixed by the coraco-clavicular ligaments to the inner fragment of the clavicle. The clavicle may be broken by rtiuscular violence alone. Polaillon, from a careful analysis of the reported cases, concludes that the muscles that break the bone are the deltoid and clavicular part of the great pectoral. In no case does the fracture appear to have been produced by the sterno-mastoid muscle. The commonest movements producing fracture appear to be violent movements of the limb forwards and inwards, or upwards. These fractures are usually about the middle of the bone, and show no displacement other than that of both fragments forwards, i.e., in the direction of the fibres of the two muscles first named. The clavicle is more frequently the seat of green -stick fracture than is any other bone in the body. Indeed, one half of the cases of broken collar bone occur before the age of five years. This is explained by the fact that the bone is ossified at a very early period, and is in a breakable condi- tion at a time when most of the other long bones still present much unossitied cartilage in their parts. Moreover, the periosteum of the clavicle is unduly thick, and not very closely attached to the bone, cir- cumstances that greatly favour subperiosteal fracture. A reference to the relations of the bone will 172 Surgical Applied Anatohiy. [Chap. xi. show that important structures may he wounded in severe fractures associated with much displacement and with sharp fragments. Several cases are reported of paralysis of the upper limb (as a rule incomplete) following upon fracture of this bone. In some cases this symptom was due to actual compression, or tearing of some of the great nerve-cords by the displaced fragments. In other cases the nerve in- jury, while due to the original accident, was yet independent of the broken clavicle. Cases are reported of wound of the subclavian artery, of the subclavian vein, of the internal jugular vein, and of the acromio- thoracic artery. In several instances the fracture has been associated with wound of the lung, with or with- out a fracture of the upper ribs. The clayicle begins to ossify before any bone in the body. At birth the entire shaft is bony, the two ends being still cartilaginous. The bone has one epiphysis for its sternal end that appears between the eighteenth and twentieth year, and joins the shaft 9;bout twenty-five. It is a mere shell, is closely surrounded by the ligaments of the sternal joint, and cannot, therefore, be well separated by accident.* Sterno-claviciilar joint.— Although this is the only articulation that directly connects the upper limb with the trunk, yet it is possessed of such considerable strength that luxation at the joint is comparatively rare. The amount of movement in the joint depends to a great extent upon the lack of adaptability between the facet on the sternum and the sternal end of the clavicle. The disproportion between these parts is maintained by the inter- articular cartilage, which reproduces only the outline * Mr. Heath [Lancet, Nov. 18, 1882) reports a case which is probably unique. It concerns a lad, aged 14, who, when in the act of bowling at cricket, tore the clavicle away from its epiphyseal cartilage, which remained in siiu. The muscle producing the accident; w^s a^jparently the pectoralis major. Chap. XL] StERNO-ClAVICULAR /OINT. 1 73 of the clavicular surface. Extensive muscular exercise appears to increase the dissimilarity between the two joint surfaces by producing enlargement of the sternal end of the collar bone. The facet on the sternum looks upwards, outwards, and a little backwards. This obliquity has important relations to respiration, for " by this backward slope of the facet the sternum is able to advance a little upon the end of the clavicle during its elevation in inspiration " (Henry Morris). The cavity of the joint is V-shaped, since the clavicle only touches the socket at its inferior angle when the arm hangs by the side. When the arm is elevated, however, the two bones are brought in more imme- diate contact, and the joint cavity becomes a mere slit. Thus, in disease of this articulation it will be found that of all movements of the joint the movement of the limb upwards is the most constant in producing pain. The movements permitted at this joint are limited, owdng to the anterior and posterior sterno- clavicular ligaments being moderately tense in all positions of the clavicle. Movement forwards of the clavicle on the sternum is checked by the posterior ligament, and resisted by the anterior ligament. This latter ligament is more lax and less sub- stantial than is the posterior band, and would be comparatively weak were it not strengthened by the tendon of the sterno-mastoid. Its weakness serves in part to explain the frequency of the dislocation forwards. Movement of the clavicle hackwards on the sternum is checked by the anterior ligament, while the passage of the head of the bone is resisted by the powerful posterior band. The movement is also opposed by the rhomboid ligament. To produce, therefore, a dislocation backwards considerable force must be used. Movement of the clavicle upiuards on the sternum is checked by the rhomboid ligament, tho interclavicular ligament, the interarticular cartilage, 174 Surgical Applied Anatomy. [Chap. xi. and in a less direct manner by the two remaining ligaments of the joint. Thus it happens that dis- location upwards is the least common of the luxations at this articulation. Disease of tlie sterno-clavicular joint. — This articulation is really divided into two joints by the interarticular cartilage, each being provided with a distinct synovial membrane. These joints are liable to the ordinary maladies of joints, and it would appear that the disease may commence in, and be for some time limited to, one only of the synovial sacs. In time the whole articulation usually becomes involved, but even in advanced cases the mischief is sometimes restricted to the synovial cavity on one side of the cartilage. According to some authors, this joint is more frequently involved in pyaemia than is any other. When effusion has taken place into the sterno-clavioular joint, and especially after suppuration has ensued, the swelling usually makes itself evident in front, owing to the fact that the anterior sterno-clavicular ligament is the thinnest and least resisting of the ligamentous structures about the articulation. !For the same reason the pus usually escapes from the anterior surface, when it discharges itself spontaneously. It may, however, make an opening for escape through the posterior ligament, and under these circumstances has found its way into the mediastinum. The relations of this joint to the great vessels at the root of the neck should be borne in mind. In one case reported by Hilton a large abscess formed in the articulation, and the collection, receiving pulsations from the subjacent artery (the innominate or right subclavian), was supposed at one time to be an aneurism. It is remarkable that disease of this joint never leads to anchylosis. This cir- cumstance may l)e explained (1) by the constant slight movement in the part which prevents the Chap. XI.] Sterno-Clavicular Joint. 175 diseased structures from being kept at rest, (2) by the occasional persistence of the interarticular cartilage, and (3) by the utter lack of adaptability of the two bony surfaces involved. Diiiilocations of the stcriio-claviculnr joint. — The clavicle may be dislocated from the sternum in one of three directions, which, given in order of fre- quency, are : (1) forwards, (2) backwards, (3) upwards. The relative frequency of these dislocations can l^e understood from what has been already said as to the action of the ligaments in restricting: movements. The displacement forwards involves entire rupture of the capsule, and more or less damage to the rhomboid ligament. The head of the bone carry- ing with it the sterno-mastoid, rests on the front of the manubrium. The dislocation backwards may be due to direct or indirect violence, and has occurred spontaneously in connection with the chest deformity in Pott's disease. The capsule is entirely torn, as is also the rhomboid ligament. The head is found in the connective tissue behind the stemo-hyoid and sterno- thyroid muscles. In this position it may cause severe dyspnoea, or dysphagia, by pressure upon the trachea or gullet. It may so compress the subclavian artery as to arrest the pulse at the wrist, or so occlude the brachio-cephalic vein as to produce semi-coma (Fig. 17). In one case the head of the bone had to be excised to relieve a troublesome dysphagia. In the luxation upv:ards^ due usually to indirect violence, the head rests on the upper border of the sternum between the sterno-mastoid and sterno- hyoid muscles. It involves more or less complete tearing of all the ligaments of the joint, together with avulsion of the interarticular fibro-cartilage. The non-adaptability of the joint surfaces in this part serves to explain the ease with which these luxations are usually reduced, and the difficulty 176 Surgical Applied Anatomy. [Chap. xi. of retaining the clavicle in position after it is re- placed. Acromio-claviciilar joint. — This articulation is shallow, and the outlines of the two bones that enter into its formation are such that no obstacle is offered to the displacement of the clavicle from the acromion. The joint, indeed, depends for its strength almost entirely upon its ligaments. The plane of the joint would be represented by a line drawn from above downwards and inwards between the two bones. This inclination of the joint surfaces serves to explain the fact that the usual luxation of this part takes the form of a displacement of the clavicle upwards on to the acromion. The capsule that surrounds the joint is lax and feebloj and it is partly from its comparative thinness that effusion into this joint, when it is the seat of disease, makes itself so soon visible. The joint, however, depends mainly for its strength upon the powerful conoid and trapezoid ligaments. As the movements permitted in this joint may be impaired by accident or disease, it is well to note the part the articulation takes in the move- ments of the extremity. The scapula (and with it, of course, the arm), as it glides forwards and back- wards upon the thorax, moves in the arc of a circle whose centre is at the sterno-clavicular joint, and whose radius is the clavicle. As the bone moves forwards it is important, for reasons to be imme- diately given, that the glenoid cavity should also be directed obliquely forwards. This latter desirable condition is brought about by means of the acromio- clavicular joint. Without this joint the whole scapula as it passed forwards with the otiter end of the clavicle would precisely follow the line of the circle above mentioned, and the glenoid cavity would look in an increasingly inward direction. It is essential that the surface of the glenoid cavity Chap. XL] Ac ROM 10- ClA VICULAR JoINT. 1 7 7 should be maintained as far as possible at right angles to the long axis of the humerus. When these relations are satisfied, the humerus has the support behind of a stout surface of bone, and it is partly to obtain the value of this support that the boxer strikes out from the side, i.e., with his humerus well backed up by the scapula. If there were no acromio-clavicular joint the glenoid fossa would offer little support to the humerus when the limb was stretched forwards, and a blow given with the limb in that position, or a fall upon the hand under like conditions, would tend to throw the humerus against the capsule of the shoulder joint, and so produce dislocation. Normally, therefore, as the scajHila and arm advance, the angle between the posterior border of the acromion and the adjacent portion of the clavicle becomes more and more acute, and the glenoid fossa is maintained with a sufficiently forward direction to give substantial support to the humerus.* It will thus be seen that rigidity of this little joint may be a cause of insecurity in the articu- lation of the shoulder, and of weakness in certain movements in the limb. Dislocations of the acromio-clavicular joint. — The clavicle may be displaced ttpwards on to the acromion or downwards beneath it. Pol- laillon has collected thirty-eight cases of the former luxation, and six only of the latter. This dis- proportion is, in the main, explained by the direc- tion of the articulating surfaces of the joint. Both luxations are usually due to direct violence. The dislocation upwards is very commonly only par- tial, and is associated only with stretching and some irifling rupture of ligaments. In the complete form, where the end of the clavicle rests entirely upon the * For an excellent account of the mechanism of these joints see Mon'is's "Anatomy of the Joints," p. 202, et seq. 1879. M 178 Surgical Applied Anatomy. [Chap. xi. acromion, there is rupture, not only of the capsule, but also to a greater or less extent of the coraco-clavicular ligaments. In the complete dislocation downwards, also, there is a rupture of the capsule, with extensive tearing of the conoid and trapezoid ligaments. These luxations are usually easily reduced, but it will be understood, from the direction of the articular surfaces, that in the displacement upwards it is very difficult to retain the clavicle in situ when once reduced. Scapula. — At the posterior aspect of the bone the muscles immediately above and below the spine are somewhat precisely bound down by the deep fascia. Thus, the supraspinatus muscle is enclosed in a fascia, that, being attached to the bone all round the origin of the muscle, forms a cavity open only towards the insertion of the muscle. The infraspinatus and teres minor muscles are also enclosed in a distinct, but much denser, fascia that is attached to the bone beyond these muscles, and blends in front with the deltoid sheath so as to form a second enclosed space. The arrangement of these fasciae serves to explain the trifling amount of ecchymosis that usually follows upon fractures of the scapular blade. The extravasation of blood about the fracture is bound down by the fasciae over these muscles, and is unable, therefore, to reach the surface. Thus also pus, in the supra- and infraspinous fossae, tends to be pent up, and to come forward in the one case at the insertion of the subscapular muscle, and in the other instance about the insertion of the teres minor. Owing to the rigidity of the fascia over the infraspinatus and teres minor muscles, it happens that dense tumours growing from this fascia may readily be mistaken for growths from the bone itself. The inferior angle of the scapula is crossed by a part of the latissimus dorsi, and by means of this muscle is retained in contact with the thorax. In certain Chap. XL] The Scapula. 179 injuries tlie angle may slij) from beneath the muscle and appear as a marked projection. This lesion is pro- ductive of some loss of power in the limb. In many- cases where this accident is supposed to have occurred, it is probable that the symptoms present are due rather to paralysis of the nerve of Bell. Fractures of the scapula, and especially of the body of the bone, are not common, owing to the mobility of the part and the thick muscles that cover in and protect its thinner portions. It rests also upon a soft muscular pad, and derives, no doubt, additional security from the elasticity of the ribs. The most common lesion is a fracture of the acromion i^rocess. This is often but a separation of the epiphysis. There are two, sometimes three, epiphy- seal centres for the acromion. Ossification appears in them about puberty, and the entire epiphysis joins with the rest of the bone from the twenty-second to the twenty-fifth year. Several cases of supposed fracture of the acromion united by fibrous tissue are probably but instances of an imperfectly-united epiphysis, and may have been independent of injury. In fractures of the l)rocess much displacement is quite uncommon, owing to the dense fibrous covering the bone derives from the two muscles attached to it. This dense periosteum also explains the circumstance that many fractures are incomplete and crepitus often absent. When the fracture is in front of the clavicular joint, displace- ment of the arm is impossible. When it involves the joint, a dislocation of the collar-bone is common. When behind the joint, the arm, having lost its support from the thorax, is displaced in somewhat the same way as obtains in the common fracture of the clavicle. The coracoid process may present a genuine fracture, or may be separated as an epi2:>hysis. As an epiphysis, it joins the main bone about the age of seventeen. In spite of the powerful muscles attached I So Surgical Applied Anatomy. [Chap. xi. to it, the displacement is usually slight, inasmuch as the coraco - clavicular ligaments are seldom torn. These ligaments, it may be noted, are attached to the base of the process. In some few cases the process has been torn off by muscular violence. Among the more usual fractures of the body of the scapula is a transverse or oblique fracture of its blade below the spine. Owing to the infraspinatus, sub- scapularis, and other muscles being attached to both fragments, none but a trifling displacement is usual. A fracture may occur through the surgical nech. The surgical neck is represented by a narrowed part of the bone behind the glenoid fossa, and in the line of the suprascapular notch. The smaller frag- ment will, therefore, include the coracoid process, the larger, the acromion. The amount of deformity in these cases depends upon whether the coraco- clavicular and acromio-clavicular ligaments are entire or torn. If they be torn, the small fragments and the entire limb are displaced downwards, and the injury somewhat resembles a subglenoid dislocation. From this, however, it is distinguished by the crepitus, by the ease with which the deformity is removed and the equal ease with which it returns, by the position of the head of the humerus in regard to the glenoid fossa, and by the conspicuous fact that the coracoid process is displaced downwards with the limb. Tumours of various kinds grow from the scapula and mainly from the spongv parts of the bone, viz., the spine, the neck, the inferior angle. The bone may be removed entire, with or without amputa- tion of the upper limb. The main vessels to be noted in connection with this operation are the supra- scapular at the superior border of the bone, the posterior scapular about the vertebral border, the subscapular running along the lower border of the Chap. XL] TiiK Axilla. i8i subscapularis musclo, the dorsalis scapula? crossing the axillary edge of the bone, and the acromial branches of the acroniio-thoracic artery. The axilla. — The axilla may be regarded sur- gically as a i)assage between the neck and the upper limb. Axillary tumours and abscesses may spread uj) into the neck, and in like manner cervical growths and purulent collections may extend to the arm-pit. The skin forming the base of the axilla is pro- "" vided with many short hairs and with numerous sebaceous and sudoriferous glands. In this in- tegument small su- A- perficial abscesses are often met with, that arise usually from suppuration of these glandular structures, and that are brought about by the friction of the skin against the Fig. 18.-Vertical Section through the Axilla , , . ^^^ . and Shonlder-jomt (Eudmger). clothing. Owing to ,^ g^^j,,,,, . 2, hun^orus; .. clavicle ; 4, acromion : «, trapezius; 6, supraspinatiis ; c, subacromial bursa and deltoid; d, circumflex artery and nerve ; e,latissinnisdorsi ; /, coraco-bracbialis and biceps; g, subscapularis; h, serratus to become chafed magnus ; i, axillary artery : j, axillary vein. and inflamed under friction, the axilla is not a good locality to select for the use of the mercurial inunction as applied in syphilis. Beneath the skin and superficial fasciae is the axillary fascia, and beyond this dense membrane is the axillary space. The connective tissue with the tendency of the axillary integument 1 82 Surgical Applied Anatomv. [Chap. xi. which the axillary space is mainly occupied is very loose, and, while this laxity favours greatly the free movement of the arm, it at the same time permits of the formation of large purulent collections and im- mense extravasations of blood. It is important to remember the disposition of the fasciae about this region. There are three layers principally concerned. (1) The deep pectoral fascia that covers in and encloses the pectoralis major. (2) The clavi-pectoral fascia that, adherent above to the clavicle, fills in the space between that bone and the pectoralis minor, then splits to invest this muscle, and joins the deep pectoral layer at the anterior fold of the axilla to form with it the axillary fascia. The upper part of this fascia is generally known as the costo-coracoid membrane. The whole membrane is sometimes known also as " the suspensory ligament of the axilla," since it draws up the axillary fascia towards the clavicle, and is mainly instrumental in producing the " hollow " of the armpit. (3) The axillary fascia, that is formed by the union of the two preceding fasciae, and stretches across the base of the axilla from its anterior to its posterior fold. Atoscess about the axillary reg^ion may be considered (1) when it is beneath the pectoralis major, or between the two pectoral muscles, and (2) when it is beneath the pectoralis minor and clavi-pectoral fascia, and therefore in the axillary space. (1) An abscess in this situation is placed between the deep pectoral and the clavi-pectoral fasciae, the latter separating it from the axillary space. Such an abscess under- mines the great pectoral, and tends to present either at the anterior margin of the axilla, or in the groove between the great pectoral and deltoid muscles, being guided thither by the attachment of the fasciae. (2) A purulent collection in the axilla may soon fill that sjDace and distend it entirely. Its progress Chap. XI.] The Axilla. 183 towards the skin is arrested by the axillary fascia, its progress backwards by the serratus magnus muscle, which, by its attachment to the scapula, hermetically closes tlie axillary space behind. In front the advance of tlie abscess is prevented by the pectoral muscles and clavi-pectoral fascia, while on the inner side is the unyielding thorax, and on the outer side the upper limb. The abscess, therefore, as it fills the axilla pushes forwards the pectoralis major, more or less obliterates the hollow of the armpit, thrusts back the scapula, and widens the angle between the serratus magnus and the subscapulars muscles. There is a great tendency, therefore, for um-elieved abscesses to extend upwards into the neck, that being the direction in which the least amount of resistance is encountered. From the neck the purulent collection may extend into the mediastinum. In one case an axillary abscess, set up by shoulder-joint disease, perforated the first intercostal space, and set up fatal pleurisy. In opening an axillary abscess, and, indeed, in most incisions into this space, the knife should be entered at the centre of the floor of the axilla, i.e., midway between the anterior and posterior margins, and near to the inner or thoracic side of the space. The vessels most likely to be damaged by an indiscreet incision are the subscapular, running along the lower border of the subscapularis muscle ; the long thoracic, following the lower border of the small pectoral ; and the main vessels lying close to the humerus. The knife, if properly entered, should be midway between the two tirst-named vessels, and quite away from the main trunks. There is an ai-tery (the external mammary) that sometimes comes off as the lowest branch of the axillary trunk, and crosses the middle of the axilla, to be distributed to the thorax below the lone: thoracic. This vessel would p.'obably be wounded in the incision above named. 184 Surgical Applied Anatomy. [Chap. xi. The artery is, however, very inconstant, is small, and is not far below the surface. It is usually met with in female subjects. I^ympliatic g-lsiuds. — The axillary glands are numerous, and of much surgical importance. They may be arranged in three sets. (1) The greater number are placed along the axillary vessels, and reach up into the neck along those vessels so as to form a chain continuous with the cervical glands. They receive mainly the lymphatics of the upper limb, and are enlarged in inflammatory and other affections of that part. (2) Other glands lie upon the serratus magnus muscle on the thoracic side of the axilla, and just behind the lower border of the pectoral muscles. They receive the lymphatics from the front of the chest, the principal lymph vessels of the breast, and the superficial lymphatics of the abdomen as low down as the umbilicus. Their eff'erent vessels for the most part pass on to join the chief axillary glands. These glands will be the first to be enlarged in certain breast affections, and after blistering and other superficial inflammations, etc., of the chest and upper abdomen. Paulet has seen them afiected in inflammation of the hand. (3) The remaining glands are situated at the back of the axilla, along the subscapular vessels. They are joined by the lymphatics from the back. It may here be convenient to note that one or two glands are commonly found in the groove between the deltoid and pectoralis major muscles. They receive some vessels from the outer side of the arm and a part of the shoulder. The superficial lymphatics over the upper pai-t of the deltoid go to the cervical glands (Tillaux), over the lower half to the axilla. The lymphatics from the supraspinous fossa follow the suprascapular artery, and join the lowest cervical glands. The superficial lymphatics of Chap. XI.] The Axilla. 185 the back that converge to the axilla are derived from the neck over the trapezius muscle, and from the whole dorsal and lumbar regions as far down as the iliac crest. The removal of axillary glands is an operation frequently undertaken. It will be understood from their position that these bodies, when diseased, are very apt to become adherent to the axillary vessels, and especially to the vein. The latter vessel has frequently been wounded during the removal of gland tumours, and in one case at least the artery was accidentally cut (Holmes). The axillary vessels. — The axillary vein is formed by the union of the basilic with the two vense comites of the brachial artery. This union commonly takes place at the lower border of the subscapular muscle, and the vein is therefore shorter than the artery. Sometimes the vein does not exist as a single trunk until just below the clavicle. This condition, when it exists, is very unfavourable to operations upon the artery, as many transverse branches cross that vessel to unite the veins that lie on either side of it. The axillary vein, being comparatively near the heart, is readily influenced as regards its contained blood by the inspiratory movement. Thus it happens that in many instances of wound of the vessel, or of its larger tributaries, air has been drawn into the venous canal and death has ensued. The entrance of air into the main vein is perhaps aided by the circumstance that the costo-coracoid membrane (upper part of clavi-pectoral fascia) is adherent to the vessel, and thus tends to maintain it in a patent condition when wounded. This connection with the fascia is supposed by some to in part ac- count for the furious bleeding that occurs from this vein when it is divided. The vein is more often wounded than is the artery, it 1 86 Surgical Applied Anatomy. [Chap. xi. being larger, more superficial, and so placed as to more or less overlap the arterial trunk. On the other hand, in injury to the vessels by traction, as, for example, in reducing dislocations, the artery suffers more frequently than the vein. In all positions of the upper limb the artery keeps to the outer angle of the axillary space. The relation of the vein, however, to the first part of the axillary artery, the part above the pectoralis minor, is modified by the position of the limb. Thus, when the arm hangs by the side the vein is to the inner side of the artery, and a little in front of it, but when the limb is at a right angle with the trunk the vein is drawn so far in front of the artery as to almost entirely conceal that vessel. Aneurism is very frequent in the axillary artery, a fact to be explained by the nearness of the vessel to the heart, by the abrupt curve it presents, by its suscepti- bility to frequent and extensive movements, and by its liability to share in the many lesions of the upper limb. In violent and extreme movements of the limb the artery may be more or less torn, especially if its walls are already diseased. In ligaturing the first part of the axillary artery it is well to note that the pectoralis major has some- times a cellular interval between two planes of muscle fibre, and this may be mistaken for the space beneath it (Heath). If the pectoralis minor has an origin from the second rib, it may more or less entirely cover the artery and require division. The cord of the brachial plexus nearest to the artery may be mistaken for that vessel, or easily included in a ligature intended for it. A ready guide to the axillary vessels in this operation is to follow the cephalic vein. In applying a ligature to the third part of the artery, it should be borne in mind that a muscular slip sometimes crosses the vessels obliquely, passing Chap. XL] The Deltoid. 187 from the latissimus dorsi to join the pectoralis major, coraco-brachialis, or biceps muscles. Tliis slip may give rise to confusion during the operation, and may be mistaken for the coraco-brachialis. The 5i.xillary nerves. — Any of the axillary nerves may be injured by a wound, the median being tlie most frequently damaged, and the musculo- spiral the least frequently. The comparative im- munity of the latter is explained by its deep position, its situation at the inner and posterior aspect of the limb, and its large size. The nerves are very seldom torn by a traction on the limb short of more or less complete avulsion. Indeed, if forcibly stretched, they ai-e disposed rather to become torn away from their attachments to the spinal cord than to give way in the axilla. Thus, Flaubert records a case where the last four cervical nerves were torn away from the cord during a violent attempt to reduce a dislocated shoulder. The deltoid reg'ion. — This region, comprising as it does the " point " of the shoulder, is limited in all parts by the deltoid muscle. The deltoid covers the upper end of the humerus and the shoulder joint. Between the joint and the surface, therefore, are only the skin and superficial fascia, the deltoid in its sheath, and some loose connective tissue (the subdeltoid tissue) in which is found the great subacromial bursa. This subdeltoid tissue sometimes assumes the form of a distinct thick membrane, and may have an important influence upon the locali- sation of purulent collections proceeding from the joint. The fatty tissue over the deltoid is a favourite seat for lipomata, and it is in this situation that the tendency of these growths to change their position is sometimes seen. Thus, Erichsen records a case where the tumour slid downwards from the shoulder to the breast. 1 88 Surgical Applied Anatomy. [Chap. xi. Emerging from the interval between the two teres muscles, and winding horizontally round the shaft of the humerus, quite close to the bone, and about the line of the surgical neck, are the circumflex nerve and posterior circumflex arterj. This nerve affords an example of an arrangement pointed out by Mr. Hilton, viz., that a principal nerve to a joint not only supplies the articular surfaces, but also some of the main muscles that move that joint and the skin over those muscles. This nerve supplies the shoulder joint, the deltoid and teres minor muscles, and the skin over the lower two-thirds of the shoulder and upper part of the triceps. "The object of such a distribution of nerves to the muscular and articular structures of a joint, in accurate association, is to ensure mechanical and physiological consent between the external muscular or moving force and the vital endurance of the parts moved, viz., of the joints, thus securing in health the true balance of force and friction until deterioration occurs" (Hilton). This nerve is frequently damaged in injuries to the shoulder. It may be severely bruised by a simple contusion of the part, and this bruising may be followed by paralysis of the deltoid. It would appear, however, that damage to the circumflex is much less frequent after contusions of the shoulder than was formerly maintained. It will also be readily understood that the nerve is often torn in fractures of the surgical neck of the humerus, in dislocations of that bone (especially the luxation backwards), and in violent attempts at reducing such dislocations. The nerve, from its position, is very apt to be seriously pressed upon by growths springing from the upper end of the humerus. From its con- nection with the joint, it follows that in chronic inflammation of that part the inflammation may extend along the nerve, producing a neuritis that may lead to paralysis of the deltoid (Erb). Chap. XI.] The Shoulder-Joint. 189 The slioiilder-joiiit. — From one surgical point of view, joints may be divided into (1) those that depend for their strength mainly upon ligaments ; (2) those that are mechanically strong, and that derive their stability to a gi'eat extent from the arrangement of their component bones ; and (3) those that rely for their support principally upon muscles. As an example of the first kind may be cited the sterno-clavicular joint, of the second form the elbow- joint, and of the third the shoulder-joint. The articu- lation the least prone to dislocation is the one that derives its strength from tough unyielding ligaments, while the one most often luxated belongs to the third variety, its strength being gi-eatly dependent upon muscles that may be taken by surprise, and that may themselves, from disordered action, prove sources of weakness. These are, of course, not the only features in the etiology of dislocation. A great deal depends upon the amount of movement permitted in a given joint, and the degree of leverage that can be brought to bear upon its parts. The arch formed by the coracoid and acromion processes and the ligament between them forms an essential support to the head of the humerus, and is an important constituent of the articulation. With this arch the humeral head is in immediate relation, although not in actual contact (Fig. 18). In paralysis of the deltoid the head may be separated by some distance from the coracoid process, and Nannoni records the case of a child with old standing paralysis of the deltoid, between whose humeral head and acro- mial vault four fingers could be lodged. It is well to note that at least two-thirds of the head of the bone are not in contact with the glenoid cavity when the arm hangs by the side, and Anger points out that in this position three-fourths of the circumference of the humeral head are in front of a vertical line drawn 190 SuRGicAi. Applied Anatomy. [Chap. xi. from the anterior border of the acromion process. In this posture, also, the head is wholly to the outer side of the coracoid process. The margin of the glenoid cavity is more prominent on the inner than on the outer side, while the strongest part of the margin and the broadest part of the fossa are below. This is sig- nificant, since it points to an attempt to strengthen a part of the joint that practice shows to be the weakest in the articulation, viz., the lower and inner portion of the capsule. It is at this place that the head of the bone leaves the joint in dislocation of the shoulder. The capsule of the shoulder-joint is very lax, and would lodge a bone-head twice as large as that of the humerus. According to Henry Morris, no one part of the capsule is constantly thicker than the rest, as is the case in the hip-joint. The inner surface of the capsule looks into the axilla, and is there free between the two tuberosities, between the lesser one in front and the posterior part of the greater process behind. It is between these two projections that the humeral head can be felt through the axilla. Of the bursse about the joint, the subacromial bursa is the one most frequently the seat of disease, and this sac, when distended with fluid, may be mis- taken for the results of chronic inflammation of the joint (Fig. 18). Experiment shows that the walls of this bursa may be actually torn in twists of the arm, especially when either flexed or extended (JSTancrede). When the sac is distended most pain is elicited in the position of abduction, for in this posture the bursal walls are normally folded up, so as to form a sort of collar in advance of the greater tuberosity. When the walls are thickened and distended by inflammation, abduc- tion must press the bursa very forcibly under the acromion, and so cause pain. In elderly people the sac sometimes communicates with the joint. Chap. XI.] The Shoulder-Joint. 19 j The biceps tendon strengthens the upper part of the joint, keeps the humerus against the gh^noid cavity in the various positions of the limb, and pre- vents the head of the bone from being pulled too closely upwards under the acromion. The tendon may be ruptured, and in such a case, in addition to the general weakening of the limb and the peculiar projection formed by the contraction of the muscle, the head of the humerus is usually drawn upwards and forwards until arrested by the coraco-acromial arch. Thus, a kind of slight false dislocation may be produced. In certain violent wrenches of the limb the tendon may slip from its groove and be displaced to one or other side, usually to the inner side. In these cases also the head is drawn up under the acromion, and is prominent in front, while abduction is rendered less free than is normal owing to the great tuberosity being sooner brought in contact with the acromion. Joiut disease. — This articulation is liable to all forms of joint disease. The capsule, as just stated, is very lax, but the humerus is kept in contact with the glenoid cavity by atmospheric pressure. In joint disease, however, the effusion may effect a considerable separation of the two bones. Braune, having pierced the glenoid cavity through the supraspinous fossa, injected tallow at considerable pressure into the joint. When fully distended the humerus was found to be separated from the scapula by more than half an inch, and this may serve to explain the lengthening of the limb often noted in joint disease of this part with much effusion. When the greatest degree of disten- sion of the capsule was reached the humerus became slightly extended and rotated in. It is significant that in shoulder-joint disease it is common for the arm to be found close to the side, the elbow carried a little back (extension), and the limb rotated inwards. This 192 Surgical Applied Anatomy. [Chap. xi. position may also be due to the rigid contraction of the muscles about the joint that is usually observed. When such contractions exist it may be iliferred that the powerful latissimus dorsi has a little advantage over its opponents, and may be answerable for the rota- tion in and slight projection backwards of the arm. There may be three diverticula from the synovial membrane: (1) One that runs some way down the bicipital groove with the tendon ; (2) a cul-de-sac beneath the subscapularis, formed by a communication between the synovial cavity and the bursa under that muscle ; and (3) a cul-de-sac of like nature beneath the infraspinatus muscle. The first-named is constant ; the second is frequently present ; the third is rare. When the joint is filled with efiusion, the capsule is evenly distended and the shoulder evenly rounded. Special projections usually occur at the seats of the diverticula. Thus a swelling often appears early in the course of a synovitis in the groove between the pectoralis major and the deltoid muscles, and this swelling may appear bilobed, being cut in two by the unyielding biceps tendon (Paulet). Fluctuation can best be felt by examining the uncovered part of the capsule in the axilla beyond the subscapular muscle. When the joint suppurates pus usually escapes at one of the cul-de-sacs just mentioned, most often through the one that follows the biceps tendon. Pus may thus extend for some way along the bicipital groove. Pus escaping through the subscapular cul-de-sac is apt to spread between the muscle and the venter of tho scapula, and to present at the lower and back part of the axilla. Purulent collections beneath the deltoid are nearly always conducted towards the anterior aspect of the limb, being unable to proceed backwards owinjj to the denseness of the fascia coverinsj in the deltoid and infraspinous muscles. In one recorded case, pus that had escaped from the shoulder-joint Chap. XL] The Shoulder-Joint. 193 followed the course of the miisculo-spiral nerve, and opened on the outer side of the elbow. The various forms of anchylosis are common at the shoulder-joint, and to afibrd a freer range of move- ment to the limb in the more intractable of these cases, Tillaux proposes to divide the clavicle. Dislocations. — Dislocations at this joint are more common than at any other joint in the body. This is explained by the shallowness of the glenoid fossa, the large size and globular shape of the head of the humerus, the extensive movements of the arm, the long leverage it affords, and the dependence of the articulation for its strength mainly upon muscles. The upper limb and shoulder are also peculiarly ex- posed to injury. The principal forms of luxation of the humerus at the shoulder are : 1. Subcoracoid^ forwards and a little downwards ; the usual form. 2. Subglenoid, do^^^lwards and a little forw^ards ; rare. 3. Subsjmious, backwards ; rare. In all complete dislocations, the head of the bone leaves the joint cavity through a rent in the capsule. In so-called " false luxations " the capsule is not torn. For example, in the cadaver, if the deltoid be divided the humeral head can be displaced under the coracoid process without rupture of the capsule, ai;d the same thing may occur during life, in cases where the muscle has long been paralysed. In all cases of dislocation at this joint the primary displacement is always downwards into the axilla. It is well kno^\^l that dislocations at the shoulder are usually due to violence applied to the limb while the arm is abducted, or to severe direct violence forcing the bone downwards. Now when the limb is abducted the head of the humerus projects below the glenoid fossa, and rests upon the inferior and least protected part of the capsule. The fibres of this N 194 Surgical Applied Anatomy. [Chap. xi. portion of the capsule being tightly stretched in this position, it requires no extraordinary force to tear the ligament and drive the bone into the axilla. Thus it happens that in luxations at this joint the rent in the capsule is at its inferior and inner aspect. The head of the bone being thus driven downwards into the axilla, may, for certain reasons, remain there (subglenoid form), or more usually it will be drawn forwards and inwards by the powerful pectoralis major, aided by other muscles whose action is now less resisted (subcoracoid form) ; and lastly, the direc- tion of the violence being applied markedly from in front, the head of the bone may be thrust backwards under the acromion or spinous processes (subspinous form). The overwhelming frequency of the subcora- coid variety is explained by the greater advantage at which those muscles act that draw the bone forwards, in comparison with those that would draw it back- wards, and by the very trifling opposition offered to the passage of the head forwards when compared with the substantial obstacles in the way of its passage back- wards under the scapular spine. Fesitures comiiioii to a^H dislocations at the shoulder. — As the roundness of the deltoid depends to a great extent upon the presence beneath it of the humeral head, and as in all these luxations (save perhaps in the slighter grades of the subspinous form) the head is removed practically from its connection with the deltoid, that muscle is always more or less flattened. This flattening is augmented by the stretching of the muscle, which in some degree is constantly present. Stretching of the deltoid in- volves abduction of the arm, and this symptom is fairly constant in all the luxations. The biceps being also more or less unduly tense, the elbow is found flexed and the fore-arm supinated. In every form there is some increase in the vertical circumference of Chap. XL] The Shoulder-Joint. 195 the axilla, since the head, having left the glenoid fossa, must occupy some, part comprised within that cir- cumference. Again, Dr. Dugas has pointed out that *' if the lingers of the injured limb can be placed by the patient, or by the surgeon, upon the sound shoulder while the elbow touches the thorax (a con- dition that obtains in the normal condition of the joint), there can be no dislocation ; and if this cannot be done there must be one, for no other injury than a dislocation can induce this physical impossi- bility." This depends upon the fact that in con- sequence of the rotundity of the thorax it is impossible for both ends of the humerus to touch it at the same time, and in luxation at the shoulder the upper end of the bone is practically touching the trunk. Lastly, from the position of the great vessels and nerves it will be seen that in the subcoracoid and subglenoid luxations the head of the bone may press injuriously upon those structures. Thus may result oedema of the limb from pressure on the veins, and severe pain- or loss of muscular power from pressure on the nerves. The artery is iTSually saved by its greater elasticity ; but Berard reports a case of displacement forwards where the axillary artery was so compressed by the humeral head as to induce gangrene of the limb. The close connection of the circumflex nerve with the humerus renders it very liable to injury, especi- ally in the subglenoid and subspinous forms of dis- location. Special anatomy of each form. — 1. Sub- coracoid.— The articular head of the humerus lies on the anterior surface of the neck of the scapula, and the anatomical neck rests on the anterior lip of the glenoid fossa. The head is thus placed immediately below the coracoid process, and is in front of^ internal to, and a little below, its normal site. The great tuberosity 196 Surgical Applied Anatomy. [Chap. xi. faces the empty glenoid cavity (Fig. 19). The sub- scapularis muscle is stretched over the head of the humerus, and is usually in some part torn. The supra- sjDinatus, infraspinatus, and teres minor are stretched torn, or the or great tuberosity may even be wrenched off. The c o r a c o - brachialis and short head of the biceps are tense, and are immediately in front of the head of the humerus instead of to its inner side. The long tendon of the biceps is deflected downwards and outwards. It is sometimes, al- though rarely, torn from its groove. The del- toid is put upon the stretch. The prominence formed by the humeral head in the front of the axilla depends to some degree upon the amount of rotation. If the bone be rotated out the projec- tion is most distinct ; but if rotated in, its head sinks into the axilla and is brought more in contact with the scapula than with the skin. The head of the bone being always carried a little downwards some lengthening must in all cases really exist ; but with the ordinary method of measuring the limb this lengthening may be replaced by a normal measure- ment, or even by apparent shortening, if the head of Fig. 19. — Subcoracoid Dislocation of the Humerus. Chap. XI.] The Shoulder-Joint. 197 the bone be carried a good deal forwards and inwards, and the limb be abducted. When the head has left the glenoid cavity abduction tends to bring the external condyle nearer to the acromion, and these are the two points between which the measurement is usually taken. Thus the apparent length of the arm depends mainly ui)on the degree of abduction of the humerus, or the obliquity of the axis of the bone. 2. Siibg-lciioid, — The head is below, and a little in front of and internal to, its normal position. It cannot go directly downwards, owing to the situa- tion of the long head of the triceps, but escapes in the interval between that muscle and the subscapularis. The articular head rests on the anterior aspect of the triangular surface just below the glenoid fossa that gives origin to the triceps. The upper border of the great tuberosity is in close relation with the lower margin of the joint. It is generally stated, on the authority of Malle, that the circumstance which pre- vents the head of the bone from being drawn upwards is the entirety of the anterior part of the capsule, the rent being in the lower part only of that ligament. The subscapularis muscle is mucli stretched or torn, and the head usually lies beneath its tendon, and upon some fibres of the disturbed muscle. The supra- spinatus will be torn. The infraspinatus will be stretched or torn, and the two teres muscles will not be much affected unless there be considerable abduc- tion of the arm. The coraco-brachialis and biceps will be stretched, but owing to the amount of abduction usually present the biceps tendon is but little deflected from a straight line. The deltoid is greatly stretched, and its tension serves to produce the extreme flatten- ing of the shoulder, and the great abduction common in this injury. Some lengthening is seldom absent, although it is always modified by the abduction that exists. 198 Surgical Applied Anatomy. [Chap. xi. 3. Subspinous. — The head usually rests on the posterior surface of the neck of the scapula, the groove of the anatomical neck of the humerus corre- sponding to the posterior lip of the glenoid fossa. The head is thus placed beneath the acromion ; but it may be displaced still farther back, and may rest on the dorsum scapulae, and beneath the scapular spine (Fig. 20). The sub- scapularis tendon is drawn right across the glenoid fossa, and is o^ten torn from it.-^ attachment. The head pushes back the hinder part of the deltoid, the infraspinatus^ and teres minor muscles. These latter cover the bone, and are stretched over it. The supraspinatus is tense, as is also the biceps, while the teres major and latissimus dorsi are relaxed. The great pectoral is rendered unduly tense, and this serves in part to explain the rotation inwards of the humerus, and the adduction forwards, that are usually observed, those movements being more or less un- opposed. The circumflex nerve is often torn. In reducing dislocations, especially such as are of long standing, serious damage may be inflicted on the axillary structures. The axillary artery sufl^'ers most frequently, the vein rarely, and the nerves still less often. The artery, being placed externally, is apt to contract adhesions to the soft parts covering the head Fifr. 20. -Subspinous Dislocation of Humerus. Chap, XI.] Upper End of Humerus. 199 of tlie displaced bone, and to be, therefore, torn when those parts are disturbed. Fractures of the upper cnf thp nlna minimi digiti ; n, extensor com- ^^S, ana HI iront Ol Llie Ullid, the flexor profundus, the latter cut much the longer. Quite close to the radius, and for the mos fc part behind it, would be the lowest part of the small supinator, while behind the ulna would be the cut fibres of the upper end of the extensor ossis. On the face of the posterior flap would be seen from without inwards the extensor carpi radialis longior and brevior, the extensor communis, the ex- tensor of the little finger, and the extensor carpi ulnaris. The radial artery will run the whole length of the anterior flap, and be cut near its outer border to the inner side of the supinator longus. The ulnar artery will be cut shorter, will be in front of the bone, and between the flexor sublimis and flexor profundus. The anterior interosseous vessels will be divided im- mediately in front of the interosseous membrane. munis digitorum ; o, extensor se- cundi interuodii poUicis ; p, exten- sor primi internodii pollicis ; q, extensor carpi radialis brevior ; r, extensor cai-pi radialis longior, with, in front of it, the extensor ossis metacarpi pollicis ; 1, radial vessels ; 2, ulnar vessels ; 3, median nerve. Chap. XV.] The Wrist and Hand. 235 The posterior interosseous vessels will be cut long, and will be found between the superficial and deep muscles. Fig. 25 shows the relation of the parts as they would be cut in a circular amputation of the limb through the lower third. CHAPTER XV. THE WRIST AND HAND. Surface smatomy. — The following structures can be made out about the wrist : Commencing at the outer side, the lower extremity and styloid process of the radius can be well defined. The bone is here superficial in front and behind. The styloid process lies more anteriorly than does the corresponding process of the ulna, and also descends about half an inch lower down the limb. The outer surface of the radius at the wrist is crossed by the tendons of the extensor ossis metacarpi and extensor primi inter- nodii pollicis. These are very distinct when the thumb is abducted, ^nd the slit-like interval between che two can be felt. About the centre of the front of the wrist is the palmaris longus tendon, which is usually the most conspicuous of tlie tendons on this aspect of the joint. It is rendered most prominent when the wrist is a little flexed, the fingers and thumbs ex- tended, and the thenar and hypothenar eminences as much approximated as possible. A little to its outer side is the larger but less prominent tendon of the flexor carpi radialis. In the narrow groove between these two tendons lies the median nerve, and on the radial side of the flexor carpi radialis is the radial 236 Surgical Applied Anatomy. [Chap. xv. artery.* Towards the inner border of the wrist the flexor carpi ulnaris tendon is evident, descending to the pisiform bone. It is rendered most distinct when the wrist is slightly flexed, and the little finger pressed forcibly into the palm. In the hollow which this posture produces between the last-named tendon and the palmaris longus lie the flexor sublimis tendons, and just to the radial side of the flexor carpi ulnaris the pulsations of the ulnar artery can be felt. Beneath the thin skin in front of the wrist a part of the plexus of veins can be seen that end in the median and anterior ulnar trunks. At the back of the wrist the following tendons can be readily distinguished from without inwards : the extensor secundi internodii, the extensor communis, and the extensor carpi ulnaris. Of these, the most prominent is the first-named. It is rendered most distinct when the thumb is forcibly abducted and extended. The tendon leads up to a small but promi- nent bony elevation on the back of the radius that marks the outer border of the osseous groove for its reception. This tendon, when it reaches the radius, points to the centre of the posterior surface of that bone, and indicates also roughly the position of the interval between the scaphoid and semilunar bones. The lower end of the ulna is very distinct. ^Vhen the hand is supine, its styloid process is exposed at the inner and posterior aspect of the wrist to the inner side of the extensor carpi ulnaris. In prona- tion, however, the process is rendered less distinct, while the head projects prominently on the posterior part of the wrist, and is found to lie between the tendons of the extensor carpi ulnaris and extensor minimi digiti. * Sometimes the superficlalis volas arises higher and is larger than usual. It then runs by the side of the radial in front of the wrist, and, giving additional volume to the pulse, has been the foundation of the so-called "double pulse." Chap, xv.j The Wrist and Hand. 237 The wrist joint— ^The tip of the styloid process of the ulna corresponds to the line of the wrist joint, and a knife entered below that point would enter the articulation. A knife entered horizontally just below the tip of the styloid process of the radius would hit the scaphoid bone. A line drawn between the two styloid processes would slope downwards and outwards, its two extremities would represent the extreme inferior limits of the radio-carpal joint, and would fairly correspond to the chord of the arc formed by the line of that joint. The line between the styloid processes would be nearly half an inch below the summit of the arch of the wrist joint. There are several folds in the skin on the front of the wrist ; of these, the lowest is the most distinct. It is a little convex downwards, precisely crosses the neck of the os magnum in the line of the third meta- carpal bone (Tillaux), and is not quite three-quarters of an inch below the arch of the wrist joint. It is about half an inch above the carpo-metacarpal joint line, and indicates very fairly the upper border of the anterior annular ligament. The palmar siorface of hand. — The palm is con- cave in the centre where the skin is adherent to the palmar fascia. This " hollow of the hand " is of some- what triangular outline, with the apex upwards. On either side are the thenar and hypothenar eminences. At the upper end of the former eminence, a bony pro- jection is felt, just below and internal to the radial styloid process, that is formed by the tubercle of the scaphoid and ridge on the trapezium. The interval separating these two processes of bone cannot always be made out. At the upper extremity of the hypothenar eminence is the projection of the pisiform bone, and just below it the unciform process can be identified. Below the hollow of the palm, and opposite the clefts between the four fingers, three little elevations are 238 Surgical Applied Anatomy. [Chap. xv. seen, especially when the first phalanges are extended, and the second and third are flexed. These corre- Fig. 26.— Surface Markings on the Palm of the Hand. The thick black lines represent the chief creases on the skin. spond to the fatty tissue between the flexor tendons and the digital slips of the palmar fascia. The Chap. XV.] The Wrist and Hand. 239 grooves that may be 'seen to separate the elevations correspond to those slips. Of the many creases in the skin of the palm three i-equire especial notice. The first starts at the wrist, between the thenar and hypothenar eminences, and marking off the former eminence from the palm ends at the outer border of the hand at tlie base of the index finger. The second fold is slightly marked. It starts from the outer border of the hand, where the first fold ends. It runs obliquely inwards across the palm with a marked inclination towards the wrist, and ends at the outer limit of the hypothenar eminence. The third, lowest, and best-marked of the folds starts from the little elevation opposite the cleft between the index and middle fingers, and runs nearly transversely to the ulnar border of the hand, crossing the hypothenar eminence at the upper end of its lower fourth. An unimportant crease running obliquely from the third to the second fold gives to these markings the outline of the letter M. The first fold is produced by the opposition of the thumb, the second mainly by the bending simultaneously of the metacarpo-phalangeal joints of the first and second fingers, and the third by the flexion of the three inner fingers. The second fold, as it crosses the third metacarpal bone, about corresponds to the lowest point of the superficial palmar arch. The third fold crosses the necks of the metacarpal bones, and indicates pretty nearly the upper limits of the synovial sheaths for the flexor tendons of the three outer fingers. A little way below this fold the palmar fascia breaks up into its four slips, and midway between the fold and the webs of the fingers lie the metacarpo-phalangeal joints. Of the transverse folds across the fronts of the fingers corresponding to the metacarpo-phalangeal and phalan- geal joints, the highest is single for the index and 240 Surgical Applied Anatomy. [Chap. xv. little finger, and double for tlie other two. It is placed nearly three-quarters of an inch below the corresponding joint. The middle folds are double for all the fingers, and are exactlv opposite the first inter- phalangeal joints. The lowest creases are single, and are placed a little above the corresponding joints (1 to 2 mm., according to Paulet). There are two single creases on the thumb corresponding to the two joints, the higher crossing the metacarpo-phalangeal articula- tion obliquely. The free edge of the web of the fingers, as measured from the palmar surface, is about three- quarters of an inch from the metacarpo-phalangeal joints. The superficial palmar arch may be repre- sented by a curved line across the palm starting from the pisiform bone and running in a line with the palmar border of the thumb when outstretched at right angles with the index finger. The deep arch is between a quarter and half an inch nearer the wrist. The digital arteries bifurcate about half an inch above the clefts between the fingers. The dorsal surface of hand. — On the outer side of the wrist, when the thumb is extended, a hollow is obvious between the extensores ossis metacarpi and primi internodii pollicis and the extensor secundi. French writers have termed this hollow "tabatiere anatomique." Across this hollow and beneath the tendons just named runs the radial artery. Under the skin over the space . can usually be seen a large vein, the cephalic vein of the thumb. Across the space also run those branches of the radial nerve that go to the dorsum of the thumb. In the floor of the " snuff- box " are the scaphoid bone and the trapezium. The extensor secundi internodii crosses the apex of the first interosseous space. The sesamoid bones of the thumb and the joint between the trapezium and the first metacarpal bone can be well made out. The latter articulation is situate on the floor of the Chap. XV.] The Wrist and Hand. 241 " tabatiere." On the. back of the hand the various tendons and the surface veins can all be well made out. Between the first and second metacarpal bones is the first dorsal interosseous muscle, which forms a conspicuous prominence when the thumb is pressed against the side of the index finger. The three rows of knuckles are formed by the proximal bones of the several joints. The wrist and hand. — The shin of the palm and of the front of the fingers is thick and dense, while that on the back of the hand is much finer. The palm, the fronts, and sides of the fingers, and the dorsal aspects of the last phalanges, all show an entire absence of hair, and of sebaceous glands. These parts are, therefore, exempt from the maladies that attack hair follicles and their gland appendages. On the doi-sum of the hand, and of the first and second rows of phalanges, there are numerous hairs and sebaceous follicles. Sweat glands are more numerous in the skin of the palm than in any other part. According to Sappey they are four times more numerous here than they are elsewhere. Krause has estimated that nearly 2,800 of these glands open upon a square inch of the palm. Only about half the number are found upon the dorsum of the hand. The profuseness with which the palm may perspire is well kno^^^l, and is very marked in certain conditions. The cutaneous nerve- supply of the hand is very free. The nerves present Pacinian bodies, which are far more numerous in the hand than in any other part, and in no i)ortion of the surface are tactile corpuscles more numerous or more highly developed. AVith the exception of the tip of the tongue, a more acute degree of tactile sensibility is met with in the hand than in any other part. The most sensitive district is the palmar surface of the third phalanx of the index finger^ while the least sensitive to tactile Q 242 Surgical Applied Anatomy. [Chap. xv. impressions is the dorsum of the hand. It may be said that the tips of the fingers are about thirty times more acute to the sense of touch than is the skin of the middle of the fore-arm, which is among the least sensitive portions of the integument as regards tactile influences. The subcutaneous tissue of the front of the hand, and especially of the palm, is scanty and dense, and somewhat resembles the subcutaneous tissue of the scalp in that the skin is closely adherent to it, and the fat it contains is arranged in minute lobules lodged in lacunae. The subcutaneous tissue on the dorsum is, on the other hand, lax^ and has but a frail association with the skin. Thus it follows that subcutaneous extravasations of blood are practically impossible in the palm, and on the anterior aspect of the fingers, while they may be very extensive on the dorsum. In like manner oedema of the extremity is conspicuously marked upon the dorsal surface, while the palm remains comparatively free even in severe cases. Surface inflammations also of the dorsum are attended with considerable swelling, while those of the front of the hand show no such feature- At the same time the adhesion of the palmar integument to the deeper parts is so close that surface wounds do not gape, and are in a position to encourage ready healing. The denseness of the integuments of the palm renders inflammation of the part extremely painful, owing to the tension that is so readily produced, whereas inflammation in the lax tissues on the dorsum may reach some magnitude without causing great pain. The palm of the hand is well adapted to meet the effects of pressure and friction. The cuticle is thick, the skin is adherent, and immediately beneath it lies the dense palmar fascia. This fascia efficiently protects the palmar nerves and the main vessels, while it must be noted that the front of the hand, and Chap. XV.] The Wrist and Hand. 243 especially the palm, is singularly free from surface veins. Indeed, the great bulk of the blood from the hand is returned by the superficial veins on the dorsum of the fingers and hand. The lym])hatics of the palm are, moreover, scanty, and very minute, whereas on the dorsum they are large and profusely distributed. The ulnar border of the palmar part of the hand is much used in pressure and in "hammering" movements, and it is significant that this surface is well protected by soft parts, and presents a singular absence of large nerves, that, if present, would be liable to sustain damage from such movements. The form of the nail varies somewhat in individuals, and, according to certain authors, there are special types of nail to be met with in some constitutional diseases. Thus are described the tubercular, the rachitic, the arthritic nail. By the Hippocratic hand is meant a hand the tips of the fingers of which are clubbed, and the nails of which are much curved. This condition would appear to be due to impeded circulation, to retardation in the return of venous blood, and perhaps also to imperfect oxygenation of that blood. It is most often met with in congenital heart disease, in phthisis, empyema, chronic lung affections, certain thoracic aneurisms, and some forms of scrofula.* There are several forms of inflammation affecting the matrix of the nail and the soft parts immediately around it (onychia, paronychia). Such inflammations lead to great deformity of the structure itself. When a nail is thrown off" by suppuration or violence a new nail is produced^ provided any of the deeper epithelial cells are left. During convalescence from certain illnesses {e.g., scarlet fever), a transveise groove will appear across all the nails. This groove * See " Scrofula and its Gland Diseases," p. 99. By tho Author. London. 1882. 244 Surgical Applied Anatomy. [Chap. xv. indicates the portion of nail formed during the illness, and by watching its movement the rate of growth of the nail can be estimated. I have more than once found these grooves useful in testing the truth of a patient's account of his more recent ailments. The nail grows at the average rate of g^nd of an inch per week. It may be noted that each digital nerve gives a special branch of large size to the pulp beneath the nail, and this serves to account for the intense pain felt when a foreign body is accidentally thrust under the nail. The fasciae. — Beneath the skin of the palm is the dense palmar fascia. This fascia gives almost as much strength to the hand as would so much bone, while its unyielding character, its comparative freedom from vessels and nerves, and its superficial position, render it admirably suited to withstand the effects of pressure. In certain circumstances this fascia, in part or in whole, contracts, and the disease known as Dupuytren's contraction is produced. In this affection the skin and subcutaneous tissue become also involved, and the fingers become fiexed. Apropos of this flexion, experiment shows that by dragging upon the fascia the first phalanx can be readily bent, and also, but with less ease, the second phalanx (Goyrand). The structures of the palm are divided into three spaces by the fasciae of the part (Fig. 27). Thus the muscles of the thenar and hypothenar eminences are both enclosed in a thin fascia proper to each eminence. The two spaces formed by these membranes are enclosed in all directions, and are capable, though only in a feeble way, of limiting suppuration when it commences in them. Between these two spaces (loges) is a third space, which is roofed in by the palmar fascia. This cavity is closed in at the sides, Ijut is open above and below. Above there is a free opening beneatli the annular ligament and along I Chap. XV.] The Wrist and Hand. 245 the flexor tendons 'into the fore-arm, wliile below there are the seven passages providc^d for by the division of the palmar fascia. Of these seven passages, four, situate at the roots of the several lingers, give passage to the flexor tendons, while the remaining three correspond to the webs between the Fig. 27.— Horizontal Section of the Hand tlirough the middle of the Thenar and Hypothenar Eminences (Tillavix). a. Metacarpal hone ; 6, first dorsal interosseous ; c, palniaris brevis ; ar region. — The muscles that form the lateral and posterior walls of the abdomen, and that fill in the interval between the iliac crest and the lowest rib, are the external oblique and latissimus dorsi, the internal oblique, the transversalis muscle and fascia lumborum, the erector spinse and quadratus lumborum. The external oblique and latissimus doi^i muscles are separated by a small triangular interval below (the triangle of Petit), but above they overlap. The interval between these two muscles may be represented by a line drawn vertically, upwards from the middle of the crest of the ilium. The outer edge of the quadratus lumborum corresponds to this line, just above the iliac crest ; but as the border of the muscle slopes upwards and backwards, it may be about an inch behind the line, at a point midway between the crest and the last rib. The edge of the muscle is overlapped by the internal oblique, and its inner half or two-thirds is overlapped by the erector spinse. The subcutaneous tissue in the lumbar region is very extensive, and is a favourite locality for chronic abscess. The looseness and extent of the tissue also permit of large extrava- sations of blood. It is in the muscles and fascia along the spine in this region that the rheumatic atfection known as lumbago has its seat. Chap. XVII.] The Abdominal Viscera. 295 Between the last rib and the iliac crest is stretched the dense fascia lumborum, the posterior aponeurosis of the trans versalis muscle. It is pierced near the rib by the last intercostal artery and nerve and near the ilium by the ilio-hypogastric nerve and its accompany- ing artery. It is along these structures that an abscess may possibly find its way through the fascia in certain cases. The fascia divides behind into three layers, to enclose in definite spaces the quadratus and erector spinse muscles. Within these spaces or compartments suppuration may be for some time limited. A lumbar abscess commencing in some adjacent part, as in the spine or in the loose tissue around the kidneys, usually spreads backwards by piercing the fascia lumborum or the quadratus muscle. It then finds its way through the internal oblique, and appears on the surface between the external oblique and latissimus dorsi muscles, and at the outer border of the erector spinse. It should be noted that the quadratus muscle is very thin, and offers little resistance to protrusions from within, while a great part of the muscle is firmly supported behind by the erector spinse. CHAPTER XYII. THE ABDOMINAL VISCERA. The peritoneum. — Certain of the viscera, as, for example, the stomach, spleen, and small intestines, are so closely invested with peritoneum that they could not be wounded without that membrane being wounded also. Inflammatory affections of such viscera are also very apt to involve the peritoneum. Other organs, such as the kidney, descending colon, pancreas, etc., 296 Surgical Applied Aisfatomy. [Chap. xvii. are so imperfectly covered with the serous membrane that a wound of those organs need not involve it, nor need it be implicated in even extensive inflam- matory changes. Large abscesses may, for instance, form about the kidney and discharge themselves through the skin without any peritonitis being induced. Spontaneous perforation of the small intes- tine must involve the peritoneum, while, on the other hand, the csecum and descending colon may become perforated and the matter escape into the subserous tissue, without the serous membrane being in any way involved. It is a strange fact that it is singularly easy to set up inflammation of the perito- neum if the membrane be approached from its inner surface, but comparatively difficult if it be approached from without. Thus a small puncture of the mem- brane may, on the one hand, lead to fatal peritonitis, while, on the other, it may be extensively torn from its attachments (as in ligaturing the common iliac artery from the side) without any peritonitis following. Or, again, a little pus escaping on the inner surface of the membrane may lead to inflam- mation, while the outer surface may be bathed with pus for a long while (as in large perityphlitic abscesses) without any peritonitis being produced. Inflammation of the peritoneum may lead to the formation of a great variety of bands and adhesions, beneath which pieces of intestine may be caught and strangulated. The peritoneum will allow of very considerable stretching, if only that stretching be effected gradu- ally. This is frequently seen in cases of gradual dis- tension of the bowel, and in the formation of the sac in hernia. Abrupt stretching of the membrane leads to certain rupture of it. The parietal peri- toneum may be ruptured by violence without damage to any of the viscera. Chap. XVII.] The Peritoneum. 297 The great oiiieiitiiiii is, from its position, very apt to be wounded. In small wounds of the front of the belly it very often protrudes, and acts as an excellent plug to prevent the escape of other and more important structures. It is often found in hernia, especially in umbilical hernia, where it is almost constant. Its limits vary, and it is said to generally incline to the left. According to Paulet, omental hernise are much more common upon the left side for this reason. The omentum, like other parts of the peritoneum, is apt to inflame, and to contract adhesions to the neighbouring parts. These adhesions are often of the greatest service in limiting inflammatory and hajmorrhagic extravasations, by matting the bowels together and forming spaces between them. In perforation of the bowel from disease, an opportune adhesion of the omentum over the aperture may prevent escape of the intestinal contents. In hernia3 the omentum generally contracts adhesions to the sac, and be- comes irreducible, or it may form a kind of second sac about the gut itself ("omental sac"). The end of the omentum, by becoming adherent to distant parts, as to the pelvic viscera, may form itself into a firmly attached band, beneath wdiich the bowel may be fatally strangled. In like manner the intestine has been strangulated through slits and holes that have developed in the omentum, usually as a result of inflammatory adhesions. When the great omentum contains much fat it must act as an excellent protection to the bowels, and must, as a layer of non-conducting material, help to maintain the equality of their temperature. The mesentery extends obliquely from the attach- ment of the transverse meso-colon, just to the left of the second lumbar vertebra, to the right iliac fossa. From this oblique direction it follows that, when 298 Surgical Applied Anatomy. [Chap. xvil hsemorrliage takes place in the abdomen on the right side of the mesentery, the blood is conducted into the right iliac fossa, when on the left side into the pelvis. This may explain the circumstance that collections of blood are more common in the right than in the left iliac fossa. Slits and holes are sometimes found in the mesentery through which intestine has been strangulated. Some of these apertures are apparently congenital, while others are due to injury. If from accident or from congenital defect a hole be foi-med in one of the layers of the mesentery, it is possible for a coil of the neighbouring small intestine to find its way through that hole and occupy the retro- peritoneal tissue between and behind the layers of the mesentery. In this way is produced the "' mesenteric hernia'' of Astley Cooper, who figures a case where the whole of the small intestine was lost to view, it having disappeared between the layers of the mesen- tery. A like condition may be met with in the meso- colon, and the whole of the small bowel has been found to have passed through an aperture in one layer of the meso-colon, to have occupied the retro- peritoneal tissue, and to have entirely hidden itself within a sac formed from the meso-colon. This con- dition was named by Cooper " meso-colic hernia." Hernise have also been described as occurring through the foramen of Winslow, The Stomach. Above. Liver, small omentum, diaphragm. In front. (From left to right) diaphragm, abdominal wall, liver. Stoniacli. Behind. Transverse meso-colon, pancreas, crura, solar lilexus, great vessels, spleen, left kidney, and capsule. Below. Great omentum, transverse colon, gastro-splenic omentum. Chap. XVII.] The Stomach. 299 When empty, the stomach lies at the back of the abdomen, beneath the liver and some way from the surface. When distended, the greater curvature is ele- vated and carried forwards, the anterior surface is turned upwards, and the posterior downwards (Fig. 34). The direction of the rotation depends upon the fixity of the smaller curvature. When dis- tended, the stomach is brought well against the anterior belly wall, and may occupy the whole of the middle line as far as the navel. Thus the stomach is much more exposed to injury when full than when empty. The cardiac orifice is situate behind the seventh left costal cartilage, about one inch from the sternum (Fig. 30). The pylorus, when the viscus is empty, lies just to the right of the middle line, from two to three inches below the sterno-xiphoid articula- tion on the level of a line drawn between the bony ends of the seventh ribs. When the stomach is distended the pylorus may be moved nearly three inches to the right (Braune). The cardiac orifice is on a level behind with the ninth dorsal spinous process, the pylorus with the twelfth dorsal spine (Fig. 31). A horizontal line drawn between the extreme tips of the tenth costal cartilages will about correspond to the lower border of the non-distended stomacli. The fundus of the stomach reaches on the left side as high as the level of the sixth sterno- chondral articulation, being a little above and behind the heart apex. The close relations of the stomach to the diaphragm and thoracic viscera serve in part to explain the shortness of breath and possible palpitation of the heart, etc., that may follow upon distension of the organ (Fig. 33). The near proximity of the heart to the stomach is illustrated by a case where a thorn (of the Prunus spinosa), half an inch long, had been swallowed, and had then found its way through the diaphragm and peri- cardium into the wall and cavity of the right ventricle. 300 Surgical Applied Anatomy. [Chap. xvii. Pig. 30,— Diagram showing the Eelatious of the Viscera to the Parietes (Anterior view). s, Stomach ; L, liver ; K, kidney ; tc, transvcrBe colon ; o, umbilicus. Chap. XVII.) The Stomach. 301 On reference to the development of the stomach, it will be seen that it is originally placed vertically in the abdomen. This position may be to a great extent maintained in adult life. The feats of an acrobat who styles himself " the sword swallower," can hardly be explained on any other supposition than that his stomach is vertical ; but whether such condition is congenital, or has been produced by the manoeuvre he practises, must be an open question. Although the mobility of the stomach is not con- siderable, yet it is frequently found to occupy both diaphragmatic and epigastric hernise. The stomach has been frequently wounded. In most cases a fatal result rapidly follows upon these injuries, for the contents of the stomach escape into the peritoneal cavity and set up an acute peritonitis. The most certainly and rapidly fatal cases, therefore, are those in which the stomach was full of food at the time of the accident. The empty stomach, being deeply placed and lying against the posterior abdominal wall in a collapsed state, is but little exposed to injury. A small punc- tured wound of the stomach need not be followed by escape of contents, since the loosely attached mucous membrane may escape from the wound and effectually plug it. The stomach has protruded through wounds in the abdominal walls, and has been returned, with no evil results following. In a few cases the belly wall in front of the stomach has been wounded, the viscus has protruded, its anterior wall has been wounded by the same injury that penetrated the pa- rietes, and a fistulous opening leading into the stomach ca\'ity has resulted. The best example of such cases is afforded by the well-known instance of Alexis St. ^Martin, the subject of so many physiological experi- ments. In this man the abdominal parietes in front of the stomach were torn away by a gunshot wound, 302 Surgical Applied Anatomy. [Chap, xvii. a part of the anterior wall of the storaach sloughed, and a permanent fistula resulted. Dr. Murcliison reports the case of a woman in whom a gastric fistula was produced by the continued pressure of a copper coin worn over the epigastric region. This coin was deliberately worn by the patient in order to excite a lesion that would arouse the sympathy of her friends. The pressure led to an ulceration that finally opened up the stomach. In many cases the fistula has been due to ulcerative diseases commencing in the stomach itself and spreading outwards. Some remarkable cases have been recorded where foreign substances have been swallowed and have lodged in the stomach. Certain of these cases serve to illustrate the capacity of the stomach, and among the most striking is an instance where the viscus at death was found to contain thirty-one entire spoon handles, each about five inches long, four half -handles, nine nails, half an iron shoe-heel, a screw, a button, and four pebbles. The whole mass weighed 2 lbs, 8 ozs. The patient was a lunatic. In spite of the narrowness of the pylorus, large substances that have been swallowed have been passed by the anus without trouble. Among these may be noted a metal joencil-case 4^ inches long, ten ounces of garden nails and fragments of crockery- ware swallowed by a lunatic ; a fork, a door-key, and other strange bodies. Needles and similar sharp substances that have been swallowed have travelled out of the stomach or bowels and have found their way to the surface at various points in the body. In a patient under my care at the London Hospital, I extracted from beneath the skin, near the groin, a needle swallowed some months previously. In a case reported in the Lancet^ a needle was ex- tracted from the middle of the thigh six months after it had been swallowed, and like instances are recorded elsewhere. Chap. XVI T.] The Stomach. 303 Oastrotomy and g:astrostoiny. — Gastrotomy consists in opening the stomach through the anterior abdominal wall for the purpose of removing a foreign body ; gastrostomy in opening the stomach in a like situation with the object of establishing a gastric fistula through which the patient may be fed in cases where the gullet is occluded by disease. The un- covered part of t]ie stomach, accessible in these opera- tions, is represented by a triangular area, bounded on tlie right by the edge of the liver, on the left by the cartilages of the eighth and ninth ribs, and below by a horizontal line passing between the tips of the tenth costal cartilages (Fig. 30). The incision in these opera- tions must be situate in this triangle, and may be made either parallel to, and about two fingers' breadth from, the free border of the costje, or along the left semi- lunar line. In the former incision the three flat muscles of the abdomen are cut through. In gastros- tomy the stomach is not opened at the time of the operation, but is merely secured to the wound, and a few days are then allowed to elapse so that adhesions may form. At the end of this time the viscus is opened. Much difficulty is occasioned by the loose- ness of the mucous membrane, which is apt to pro- trude at the wound by reason of its great laxity. Resection of the pylorus. — The pyloi^is is frequently the seat of cancer. As a means of re- lieving the patient of this fatal disease, Billroth and others have removed the whole of the diseased pylorus, and have then united by sutures the cut ends of the stomach and duodenum and closed the abdominal wound. The situation of the cancerous pylorus within the abdomen varies considerably, as the diseased part is very apt to shift its position. It is often found to have sunk down by its weight to a point below the umbilicus, and to have contracted adhesions to adjacent organs. The usual incision is 304 Surgical Applied Anatomy. [Chap. xvii. Fig. 31.- -Diagram to show the Eelations of the Viscera to the Parietes (Posterior view). B, Stomach; L, liver; k, kidney; sp, spleen; E, rectum. Chap. XVII.] The Small Intestines. 305 transverse, or nearly so, is about four or five inches in length, and is commonly made across the middle line just above the umbilicus. The diseased part has to be isolated and the omental connections of the right end of the stomach freely divided. The vessels that require most attention are the pyloric branch of the hepatic artery and the gastro-epiploica dextra from the same vessel. The cancer is excised, and the cut end of the duodenum united to the cut edges of the stomach, so as to re-establish the canal. The details of the operation are very complicated, and need not be here more fully dealt with, further than to say that since the section of the stomach must be much greater than that of the duodenum, the aperture in the former viscus is united by sutures until the gap left is equivalent in calibre to that of the divided duodenum. The small intestines.— The length of the small intestine is about twenty feet, of which eight feet are contributed by the jejunum and twelve by the ileum. The length of the duodenum is about ten inches. The division into jejunum and ileum is quite arbi- ti'ary. There is no one point where it can be said that the jejunum ends and the ileum commences. AV^hen the small intestines are exposed by accident or operation, it is often difficult, especially when there is abdominal disease, to recognise the upper from the lower part of the gut. It may be noted, however, that the coils of the jejunum occupy mainly the left lumbar and left iliac regions, and a part of the umbilical area, while the ileum occupies rather the right lumbar and iliac regions, the hypogastric area, and a part also of the umbilical. The jejunum is wider than the ileum (its diameter being a quarter of an inch gi'eater than that of the ileum), and its coats are thicker and more vascular. If the gut be empty, and can be rendered translucent by being held against a U m. o 06 Surgical Applied Anatomy. [Chap. xvii. light, the lines of the valvulse conniventes can be woll seen. These folds are large and numerous in the jejunum, but become small and scanty in the upper ileum, and are wanting in the lower third of that bowel. Injuries to the jejunum are more serious than are those to the ileum, since an intestinal lesion is (other things being equal) the more serious the nearer it approaches to the stomach. The fatality of umbilical hernise probably depends in part upon the fact that the contained bowel is usually jejunum. Of all the viscera the small intestines are the most exposed to injury, and at the same time it must be noted that by their elasticity, and by the ease with which their coils slide over one another and so elude the effects of pressure, they are the best adapted to meet such injuries as contusions and the like. A minute punc- tured wound of the small gut does not lead to extra- vasation of contents. The muscular coat contracts and closes the little opening. Thus, in excessive tympanitis the bowels are often freely punctured in many places with a fine capillary trochar, to allow the gas to escape, without any evil resulting. A case of intestinal obstruction of sixteen weeks' duration is reported, in which the abdomen was punctured 150 times {Boston Med. Journ.). If the wound be a little larger the loose mucous membrane be- comes everted or protruded through the wound and effectually plugs it. Gross found that a longitudinal cut in the small bowel two and a half lines in length was immediately reduced to a wound one and three- quarter lines in length by muscular contraction, and that the eversion of the mucous membrane in addition to this contraction entirely sealed the opening. Owing to the greater power of the circular layer of muscle a longitudinal wound gapes more than a Chap. XVII.] The Small Intestines. 307 transverse, and, in consequence of tlie greater mus- cular development of the jejunum, wounds of that part gape more than do those of the ileum. Transverse wounds gape most when inflicted across the free border of the gut, since in that place the longitudinal muscular fibres are thickest. In one remarkable case a man was stabbed in the belly. It was subsequently found that there was a small punctwre in the ileum, which had been plugged by the mucous membrane, and further secured by recent lymph. The man did well until the fourth day, when he died somewhat suddenly. It was then found that an intestinal worm (ascaris lumbricoides) had worked its way through the wound, breaking down the adhesions, and had escaped into the peritoneal cavity. Extravasation followed, and thus the worm was the immediate cause of the man's death. Any part of the small gut may be ruptured by severe contusions. The calibre of any piece of the intestine depends mainly upon the condition of its muscular wall. In peritonitis and in certain other conditions the muscular coat is paralysed and the bowel becomes intensely dilated by gas (tympanitis). The second and third parts of the duodenum are the most fixed portions of the small bowel, and the only parts that have not a complete peritoneal investment. The termination of the duodenum is held in place by a strong fibrous band that descends from the left crus, so that, no matter how much the gut may be disturbed by distension, that part will still retain a constant position. It will be understood that the duodenum, if approached from behind, may be wounded without injuring the peritoneum, since it has a large non-peritoneal surface (Fig. 33). On account of their fixed position the second and third parts of tlie duodenum are never herniated. In coiniection with 3o8 Surgical Applied Anatomy. [Chap. xvii. the spread of disease by continuity of tissue, it is well to note that these two parts of the bowel are only separated by connective tissue from the aorta, vena cava, spine, renal vessels, left kidney, back of the hepatic flexure of the colon, and the head of the pancreas. In the duodenum are Brunner's glands, which are sometimes the seat of a perforating nicer in cases of burn. They are mostly seated in the first part of this bowel, and the perforation, therefore, usually opens into the peritoneal cavity, the first part of the gut being almost entirely covered by peritoneum. The ileum is the part of the intestine that is the most frequently found in external herniEe. It is also the part that most usually is involved in cases of strangulation by internal bands, and by the borders of abnormal slits in the mesentery, etc. From one to three feet from the end of the ileum is sometimes seen a diverticulum (Meckel's) that represents the remains of the vitello-intestinal duct. This diverti- culum usually exists as a tube of the same structure as the intestine. Its length varies. It may sometimes extend as a patent tube as far as the umbilicus. It is more often but a few inches long, and may then end in a free conical or globular extremity, or in a fibrous cord. This diverticulum may cause intestinal obstruction in many ways. Its end may contract adhesions, and be- neath the bridge thus formed a loop of bowel may be strangled. It may twist itself about a piece of intes- tine so as to form a knot around it. It may, from its adhesions, so drag upon the ileum as to cause " kink- ing " of the tube at its point of origin. In more than one case it has been found in an external hernia. Owing to the presence of the ileo-csecal valve, it is about the ileo-C£ecal region that obstruction from foreign bodies usually occurs. Foreign bodies that have been swallowed, as well as immense gall-stones that have passed from the gall bladder to the small gut Chap. XVII.] The Small Intestines. 309 hy a direct ulcerative process, have been lodgecl here, and have caused fatal results. Some most remarkable substances have, however, been passed with safety tlirough the valve ; and, in addition to those mentioned when speaking of the stomach (page 302), instances may be given where an irregular gold plate, fixing several teeth and provided with one or two hook-like processes, has been swallowed and passed per anum without trouble. Other substances are not so easily passed. Thus, in the intestines of one lunatic were found three cotton reels, two bandages partly unrolled, some skeins of thread, and a pair of braces. It is in the ileo-csecal region, moreover, that intussusception most frequently occurs. In this condition one part of the bowel is prolapsed, or " telescoped," into another, and more or less obstruction ensues. In the present locality the narrow ileum is prolapsed or intussuscepted into the capacious csecum. Sometimes it is prolapsed through the valve, while in other instances the ileum and valve sink into the colon entire, the valve forming the summit of the "intus- susceptum." By a gradual increase of the condition it may at last happen that the intussuscepted bowel will reach the ileum ; and the ileo-ciecal valve has, in fact, been recognised protruding from the anus. Liaparotomy. — In this procedure the abdomen is opened from in front for the purpose of exploration, or for the relief of a piece of bowel strangulated by a band, and under certain other circumstances. It much more frequently concerns the small bowel than the large. The incision is usually made in the middle line below the umbilicus, and a cut from three to four inches long is usually found to be sufficient. It may be made in either of the semi-lunar lines or over any spot especially indicated by the disease. Enterotomy is the operation of opening the small intestine above some obstruction that threatens to be 3IO Surgical Applied Anatomy. [Chap. xvii. fatal. The incision is made in one or other iliac region parallel to Poupart's ligament and some little way above it, and to the outer side of the epigastric artery. The cut, which is about three inches in length, extends through the three flat muscles of the abdomen ; the peritoneum is incised, a knuckle of small intestine is secured to the wound and is then opened. Resection. — Portions of the small intestine have been resected with success for various diseased condi- tions. In one case more than two yards of the small intestine were cut away, and the patient (a young woman) made an excellent recovery. The large intestine. — From the caecum to the sigmoid flexure, this jjortion of the bowel is accessible to pressure except at the hepatic and splenic flexures, which are deeply placed. The hepatic flexure is under the shadow of the liver, and the splenic curve, which reaches a higher level, is behind the stomach. The position of the transverse colon can often be well marked out. It crosses the belly transversely, so that its lower border is on a level with the umbilicus (Fig. 30). In cases of fsecal accumulation, the outline of the colon, with the exception of the two flexures above named, may be distinctly defined. In distension of the small intestine the belly tends to present the greatest degree of swelling in front, and about and below the navel. In distension of the larger gut, the front of the abdomen may remain (for a while at least) com- paratively flat, while the distension will be most obvious in the two flanks and in the region just aVjove the umbilicus. Tumours of the transverse colon, and of the lower two-thirds of the ascending and descend- ing colon, can be well defined, even when of moderate size, and in cases of intussusception the progress of the mass along the colon can often be traced with great ease, and the effects of enemata and other methods of Chap. XVII.] The Colon. 311 reduction carefully watched. The diameter of the large intestine (excluding the rectum) gradually diminishes from the caecum to the sigmoid liexure, the diameter of the former being about two and a half inches, of the latter one and a half inches. The narrowest part of this segment of the bowel is at the point of junction of the sigmoid flexure with the rectum, and it is significant that it is at this point that stricture is the most common. The ccBcuin is said to be rudimentary in man and in the carnivora. In herbivorous animals it is of great size, and appears to serve as a reservoir for the elaboration and absorption of food, since its removal causes great emaciation. In man, therefore, the caecum has been said to exist as an anatomical protest against vegetarianism. The caecum is covered in front, below, and at the sides with peritoneum, the lower rounded end being completely invested, while its posterior surface is connected by a great deal of loose areolar tissue with the iliac fascia. It is in this loose tissue that inflammation spreads in cases of perityphlitis, an inflammation that usually originates in the ctecum, and is often due to a perforation on the posterior surface of that part of the colon. The caecum when first developed has an extensive mesentery. This condition may sometimes be found in the foetus at birth, and may persist during life. The meso-C£ecum may be long enough to allow the caecum to be herniated at the umbilicus or even on the left side. Foreign bodies that have been swallowed are very apt to lodge in the caecum, and to cause ulceration and perforation of that bowel by their impaction. It is significant that the otter has no caecum. This animal lives largely on fish, and must swallow a number of fish-bones. Had it a csiecura it would pro- bably soon fall a victim to perityphlitis and its eft'ects. 312 Surgical Applied Anatomy. [Chap. xvii. Intestinal calculi and concretions are also more often met with in the csecum than in any other part of the bowel. In distension of the colon from obstruction the csecum suffers the most severely, and appears to bear the brunt of the pressure exercised from within. The csecum has been ruptured by forcible enemata admini- stered per rectum, while the rest of the colon has re- mained intact. In many cases of great fsecal accumula- tion death has been due to perforation of the csecum as an effect of extreme pressure, and in less severe cases the peritoneum over the csecum has been found to be ruptured, while it has remained sound over the re- mainder of the larger bowel. This part of the intes- tine is susceptible of enormous distension, provided that it be gradually effected, and in certain instances an engorged csecum has been found to occupy a large part of the abdominal cavity. When the ab- domen is opened in any doubtful case of intestinal obstruction the condition of the csecum is of s:reat value in pointing to the seat of the obstacle. In closure of the colon it will be found greatly distended, while in obstruction of the small gut it will be empty, or at least in a normal condition. The tip of the vermiforrrv apiiendix may adhere to a neighbouring peritoneal surface, and thus form a ''band," beneath which a piece of the small gut may be strangled. It is favourably placed for the accumu- lation of intestinal concretions and in it foreign bodies are apt to lodge. Tor these and other reasons it happens that ulceration of the appendix is a frequent cause of perityphlitis. As regards the colon generally, the tendency to stricture increases as one proceeds downwards from the csecum to the anus. A stricture is frequent in the descending colon, and is still more common at the point of junction of the sigmoid flexure with the rectum. In the ascending colon it is comparatively Chap. XVII.] The Colon. 313 rare. When gradually distended the colon may as- sume enormous dimensions, and it will be readily understood that in some cases of great faecal accumu- lation the thoracic organs may, with certain abdominal viscera, be displaced. In one case, for example, the heart was so displaced by the distended colon that the apex beat was found to be one and a half inches above and one inch to the inner side of the left nipple. When the fsecal collection had been removed it returned to its normal position. Thus it happens that a distended colon is often associated with short- ness of breath, with palpitation, and other thoracic symptoms. The right-hand part of the transverse colon is in in- timate relation with the gall bladder, and is commonly found to be bile-stained after death. In some cases where gall stones have been lodged within the gall bladder, the walls of that structure have ulcerated from pressure, the ulceration has involved the sub- jacent transverse colon, and thus a fistula has been established between the gall bladder and the gut, through which large stones have been passed. Hepatic abscesses also have discharged themselves through the transverse colon. The anatomical arrangement of the sigmoid flexure, together with its great mobility, render it more liable to obstruction by twist or volvulus, than is any other part of the intestinal tube. The condition that especially predisposes to volvulus is a narrow root to the sigmoid meso-colon, whereby the two ends of the loop of gut are brought close together, and thus a pedicle is formed, which may readily be twisted ujDon its own axis by any rotation of the loop of bowel. In cases of congenital absence, or deficiency of the rectum, it is commonly advised that the sigmoid flexure be opened in the groin and an artificial anus established there. This operation, known as Littre's operation, 314 Surgical Applied Anatomy. [Chap. xvii. is, it must be confessed, not very successful. One difficulty lias been said to depend upon the uncertain position of the sigmoid flexure in cases of congenital deformity, it being sometimes on the right side and sometimes in the pelvis at the middle line. Surgeons have, indeed, advised that in these cases the right groin be always made the seat of operation, since the sigmoid flexure Ttiay be found there^ and if it is not present in that place there is at least the csecum that may be opened. Tliis procedure would avoid the inconve- nience of opening the left iliac region and finding it unoccupied by bowel. The frequency with which the sigmoid flexure is misplaced in young infants is shown in the following record. In 150 autopsies on young infants, Bourcart found the sigmoid flexure on the left side in 111 cases, on the right in 33, and in the pelvis in 6. In 134 autopsies by Giraldes, the gut was found in its proper place in 114 instances ; and out of 100 like post-mortem examinations on young infants. Curling found it on the left side in 85 cases. Congfenital maLformations of the colon. — These are of moment with regard to operative pro- cedures. It may be very briefly said, that in the foetus the small bowel occupies at one time the right side of the abdomen, while the large gut is represented by a straight tube that passes on the left side vertically from the region of the umbilicus to the pelvis. The csecum is at first situated within the umbilicus, and then ascends in the abdomen towards the left hypochon- drium. It next passes transversely to the right hypo- chondrium, and then descends into the corresponding iliac fossa. It may be permanently arrested at any part of its course. Thus the caecum may be found about the umbilicus, or in the left hypochondriac region (the ascending and transverse parts of the colon being absent), or it may be found in the right hypochondrium, Chap. XVII.] The Colon. 315 the ascending colon only being unrepresented.* Tlie whole of the larije intestine has at one time an exten- sive mesentery, and in some rare cases this condition may persist throughout life. Liiiiiibar colotoiiiy. — The operation so named consists in opening the colon in the loin behind the peritoneum, for the purpose of establishing an arti- ficial anus. The operation is performed, when possible, upon the left side, in preference to the right, inasmuch as the descending colon is nearer to the anus, is more fixed than is the ascending colon, and has the larger non-peritoneal surface. A meso-colon, moreover, is more commonly met with in the ascending than in the descending part of the large intestine. The position of the descending colon may be represented by a line drawn vertically upwards from a point half-an-inch behind the centre of the iliac crest. In performing left lumbar colotomy an ink line may be drawn vertically upwards from the centre of the crest of the ileum. It will hit the outer end of the last rib. An incision is made across the centre of this line parallel to the last rib, and so planned that the centre of the incision corresponds to the centre of the line. The superficial tissues having been incised, the following structures are then divided in layers in the following order: (1) The latissimus dorsi and external oblique muscles to an equal extent. (2) The internal oblique in the entire length of the incision. (3) The ftiscia lumborum, with a few of the most posterior fibres of the transversalis muscle. (•1) The transversalis fascia. The quadratus lumborum will be exposed in the posterior inch or so of the incision, and usually does not need to be cut. At the seat of the operation the descending colon occupies the angle * See a valuable and exhaustive paper on the subject of these malformations in the Brit. Med. Joixr. (vol. ii., 1882, p. 574), by Mr. C. B. Lockwood. i6 Surgical Applied Anatomy. [Chap. xvii. between the psoas and quadratus lumborum muscles, and the non-peritoneal surface is exactly represented by that part of the bowel that faces this angle Fig. 32. — Horizontal Section througli the Body at tlie Level of the Umbilicus. (Ajter Braune.) a, Spine of the fourth lumljar Yertebra ; 6, disc between third and fourth verte- bra3 ; c, umbiliciia ; d, ijuadrarAis luraborum ; e, psoas ; /, external oblique, witb internal oblique and transversalis muscles beyond; (/.rectus; /(, de- scending colon ; i, transverse colon ; j, aorta ; k, inferior vena cava ; I, ureter. (Fig. 32). Thus, if during the operation the curved finger be placed in this angle, and the patient be rolled over to the left side, the bowel that falls into the finger cannot well be other than the descend- ing colon. The gut is drawn forwards, stitched to the wound, and opened by a transverse cut. The Chap. XVII.] The Colon. 317 width of the non-peritoneal surface varies from four- fifths of an inch to an inch in the empty state, and may attain to two inches or more in the distended condition (Braune). The part of the descending colon usually opened is the highest portion of that bowel, so that the linger can often be thrust into the transverse colon, or the opening of that intestine can be seen. In this, or in other circumstances, the large bowel may be distinguished from the small by its sacculi, its three longitudinal muscular bands, and its appendices epi- ploicse. As regards dimensions, the small intestine may, especially in cases of obstruction, be much larger than the so-called large intestine. When empty, the diameter of the descending colon is about equal to that of the jejunum, the measurement in the two cases being about one and a half inches. The average dia- meter of the ileum is one and a quarter inches, and of the csecum and commencing colon two and a half inches. Lumbar colotomy is often performed through a vertical or oblique incision in the place of the one just given. The operation does not materially differ from that described, when it is performed on the right side. Colectomy consists in resecting a portion of either the ascending or descending colon that is the seat of a carcinomatous or other stricture. It is most con- veniently performed in the lumbar region, and then involves the formation of an artificial anus that will probably be permanent. Colectomy, may, however, be carried out through an incision in the middle line ; in such a case the ends of the divided bowel are united, and the abdominal wound closed.* Lumbar colectomy may be performed through any one of the incisions practised in colotomy. * See " Resection of Portions of Intestine," by the author. Trans. Eoyal Med.-Chir. Soc, 18S2. 3i8 Surgical Applied Anatomy. [Chap. xvii. The liver. — The liver is moulded to the arch of the diaphragm, and lies over a part of the stomach (Fig. 34). The convex surface is protected on the right side by the ribs, from the seventh to the eleventh inclusive, and in front by the xiphoid cartilage and the costse from the sixth to the ninth inclusive, the diaphragm being interposed. The diaphragm separates the liver from the thin margin of the base of the right lung, which descends in front of it. It extends to the left about one and a half inches beyond the left margin of the sternum. In the middle line the liver lies close beneath the skin in front of the stomach, and reaches about half way between the xiphoid cartilage and the navel. The lower edge, as it crosses the subcostal angle, is represented by a line drawn from the ninth right to the eighth left costal cartilage (Quain) (Fig. 30). In the erect posture the lower edge on the right side is about half or quarter of an inch below the margins of the costal cartilages. In the recumbent position the liver ascends about an inch, and is entirely covered by the costse, except at the subcostal angle. It descends also in inspiration and rises in expiration. " The extent of the liver upwards, if traced on the surface of the body, is indicated by a line crossing the mesosternum close to its lower end, and rising on the right side to the level of the fifth chondrosternal articulation, and on the left to that of the sixth " (Quain). Behind, the liver comes to the surface below the right lung, at a part corresponding, both in position and width, to the tenth and eleventh dorsal vertebrae. On the extreme right, the liver descends to the level of the second lumbar spine (Figs. 31 and 33). The fundus of the gall bladder approaches the surface behind the ninth costal cartilage, close to the outer border of the right rectus muscle. The liver is more often rujjtured from contusions than is any other abdominal viscus. This is explained Chap. XVII.] The Liver. 319 by its larcjp size, its comparatively fixed position, and its great friability of structure. Death, in such injuries, usually ensues from haemorrhage, since the walls of the portal and hepatic veins, being incorporated with the liver substance, are unable to retract or to collapse. The hepatic veins also open direct into the vena cava, and being unprovided with valves, could allow of the escape of an immense quantity of blood, if any retro- grade current were established. It is possi])le for the liver to be ruptured without the peritoneal coat being damaged. Such injuries may be readily recovered from. The liver presents, behind, a fairly extensive non-peritoneal surface, at which rupture or wound may occur without extravasation into the abdominal cavity. From the relation of the liver to the right lower ribs, it follows that this viscus may be damaged when the ribs are fractured, and in some cases the broken ends of the bones have been driven through the diaphragm into the liver substance. Stahs through the sixth or seventh right intercostal space, over the liver region, would wound both the lung and the liver, would involve the diaphragm, and open. up both the pleural and peri- toneal cavities. The intimate relation of the liver to the transverse colon is illustrated by a case where a tooth- pick, four inches in length, was found in the substance of the liver. It had worked its way there, from the colon, along an abscess cavity that connected the two viscera. The relation of the liver to the heart may be illustrated by a case still more remarkable. In this instance, a loose piece of liver, weighing one drachm, was found in the pulmonary artery. The patient had been crushed between two waggons, the liver was ruptured, and the diaphragm torn. A piece of the liver had been squeezed along the vena cava into the right auricle, whence it had passed into the right ventricle, and so into the pulmonary artery. The heart itself was quite uninjured. Portions of the liver may protrude through 320 SuRGiCA L Applied Ana to my. [Chap. xvii. Fig. 33.— View of some of the Abdominal Viscera from behind (Eiidiuger). a, Thoracic norta; h, oesophapriis ; c, common carotid artery and internal jnpular vein ; d, root, of riKht lung : e, inferior vena cava ; /, spleen ; g, stomacli, ;nicl to its rit'ht the liver; ft, pancreas ; i, descending part of duodenum (oi)ened); j, superior mesenteric vein joined by si)lenic aliove ; fc, ascending c(.)Ion ; I, de. Bcending colon ; m, superior hiEinorrJioidal vein joining inferior mesenteriCi Chap. XVII.] The Li ver . 321 abdominal wounds, and are usually easy to reduce. In one instance of such protrusion the surgeon did not find the reduction easy, so he placed a ligature round the projecting part of the viscus, and then cut this obstinate portion of the liver off. The patient recovered. From a reference to the relations of the liver, it will be readily understood that an hejyatic abscess may open into the pleura, and in some cases, indeed, the pus from the liver has been discharged by the bronchi Tlius, it has been possible for a patient to cough up some portion of his liver, although, of course, in a very disintegrated and minute form. Hepatic abscess may also readily open into either the duodenum or the trans- verse colon. The li^'er is very frequently the seat of the secondary abscess of pyjemia, and, according to Mr. Bryant's statistics, abscesses in this viscus are more common after injuries to the head, than after injuries elsewhere. They are rare in pyaemia following affec- tions of the urinary organs, and are equally rare in the pyaemia after burns. The liver is more often the seat of hydatid cyst than are all the viscera taken together. The cyst may discharge itself externally, or into the pleural or pei-itoneal cavities^ or into any adjacent part of the intestine. The gall bladder and the bile duct have been ruptured alone without rupture of the liver. The injury is rapidly fatal, owing to the escape of bile into the peritoneal cavity. The gall bladder is often occu- pied by gall stones. These concretions are composed mainly of cholesterin, and vary in size from a hemp seed to a hen's egg. Although the common bile duct is only about three lines in width, it is remarkable to note what comparatively large stones have been passed along it. Gall stones have suppurated out through the anterior belly wall, and have been removed from abscesses in the parietes. Thus Dr. Burney Yeo reports a case where more than one hundred gall stones were V 322 Surgical Applied Anatomy. [Chap. xvii. discharged througli a spontaneous fistula in the hypo- gastric region, five inches below the umbilicus. In cases where the bile duct is occluded by gall stones, or by other causes, the gall bladder may become enormously distended, and may form a tumour extending some way beyond the umbilicus. For the relief of this condition, cholecystotomy, or incision into the gall bladder, has been performed. In this operation, the incision or puncture is made over the most prominent part of the tumour. The Spleeit In front. Stomach. Splenic flexure of colon. Outer side. Diaphragm. 9th to 11th ribs between axillary lines. Spleen. Inner side. Stomach. Pancreas, L. kidney and capsule. Behind. Diaphragm, The spleen. — The spleen most closely approaches the surface in the parts covered by the tenth and eleventh ribs. Above this it is entirely overlapped })y the edge of the lung. It is in all parts separated from the parietes by the diaphragm. " It lies very obliquely, its long axis coinciding almost exactly with the line of the tenth rib- Its highest and lowest points are on a level, respectively, with the ninth dorsal and first lumbar spines ; its inner end is distant about an inch and a half from the median plane of the body, and its outer end about reaches the mid-axillary line " (Quain) (Figs, 31, 33, and 34). Injuries. — Although extremely friable in structure, the normal spleen is not very frequently ruptured. Its connections, indeed, tend to minimise the effects of concussions and contusions. It is swung up by the peritoneum, rests upon the elastic costo-colic fold, and Chap. XVII.] The Spleen. is protected by the stomach and lungs to a considerable extent. When the spleen, however, is enlarged, it is very readily ruptured, and often by quite insignificant violence. Thus, several cases have been recorded of rupture of an enlarged spleen by muscular violence. For instance, a woman ruptured her spleen in an -a Fig. 34. -Horizontal Section through Upper part of Abdomen (Riidmger). a. Liver; B, stomacb ; c, transverse colon ; rf, spleen ; e, kidneys ; f, pancreas ; g, inferior vena cava ; ft, aorta with thoracic duct behind it. attempt to save herself from falling, and another in springing aside to avoid a blow. The patients in each instance were natives of India, and the latter case gave rise to a charge of homicide. The spleen being ex- tremely vascular, it follows that ruptures of the viscus are usually, but not necessarily, fatal from haemorrhage. It is well to note, in connection with this matter, that the spleen contains most blood during digestion. A case is reported, however, of a boy, who met with an accident just after dinner, and who managed to walk 324 Surgical Applied Anatomy. [Chap. xvii. some distance, although his spleen, as the autopsy revealed, was separated into three portions. He lived some days. In severe fractures of the ninth, tenth, and eleventh ribs, the spleen may be damaged and lacerated. The capsule of the spleen contains muscular tissue, and must possess some contractile power. This fact may serve to explain cases of recovery from limited wounds of the organ, such as small gunshot wounds. In such lesions the capsule may contract and greatly narrow the hole in the viscus, while the tract of the bullet or knife may become filled with blood clot, and the bleeding thus be stayed. The spleen may be greatly enlarged in certain diseased conditions. The hypertrophied spleen may attain such dimensions as to till nearly the whole abdomen, and in one case a cystic tumour so com- pletely occupied both iliac fossae, that it was mistaken for an ovarian cyst, and the operation for ovariotomy was commenced. It is said that the enlarged spleen, in its earlier stages, encroaches upon the thoracic cavity, relatively more in the child than in the adult. This is explained by the statement that the costo-colic fold, upon which the spleen rests, is much more resisting in the young than it is in those of more mature age. Extirpation of tlie spleen has been very successful in cases of abdominal wounds with pro- trusion of the viscus. It has also been performed with good results in many cases of hypertrophied spleen. The operation is not considered justifiable in cases of leucsemic enlargement of the organ, it having proved invariably fatal in such instances. In cases of wounds with protrusion, the spleen is, of course, re- moved through the wound. In other instances the incision is usually made in the middle line, the most convenient being one so arranged that the umbilicus Chap. XVII.] The Pancreas. 325 corresponds to the centre of the cut. The viscus is then slowly pressed out of the wound. The only- difficulty is with the gastro-splenic omentum, which has to be divided and its vessels secured. The pancreas lies behind the stomach, in front of the first lumbar vertebra. It crosses the middle line on a level with a point about three inches above the umbilicus. In emaciated subjects, and when the stomach and colon are empty, it may sometimes be felt on deep pressure. It is in relation with many most important structures, but presents but little surgical interest (Figs. 33 and 34). It has, I believe, never been ruptured alone, and it could scarcely be wounded without the wound implicating other and more important viscera. It has been found herniated in some very rare cases of diaphragmatic hernia, but never alone. It may. become invaginated into the intestine, and portions of the gland have sloughed off and been passed in the stools. In resections of the jDylorus and spleen it is undesirable that a ligature be placed on any part of the pancreas during the operation. There are two reasons for this precaution : " First, we know that after ligature of the parotid (a gland of like character to the pancreas) great swelling and numer- ous small abscesses not infrequently form, leading to necrosis of portion of the gland ; secondly, there is some fear that (in pyloric resections) the secretion escaping from the pancreas may dissolve the cicatrix of the stomach by its peptonising properties" (Billroth). The common bile-duct is covered by, or included in, the head of the pancreas. It thus happens that in carcinoma of this part of the gland the duct may become entirely occluded and jaundice result. Or the duodenum and even the colon may be more or less obstructed by pressure, or the neighbouring vessels be closed. 326 Surgical Applied Anatomy. [Chap. xvii. Bight. TJnder siirface of liver. Duodenum. Comiaence- luent of transverse colon. Ascending colon. The Kidney. In front. Left. Fundus of stomach.. Descending col n. Pancreas. Externally. (On left side) Spleen. Behind. Lower part of arch, of diaphragm. Quadaratus lumbormn. Psoas. The kidneys are deeply placed, and cannot be felt and distinctly identified when normal. They are most accessible to pressure at the outer edge of the erector spinae, just below the last rib. The right kidney lies about three-quarters of an inch lower down than does the left ; but even the lower end of the right gland barely reaches to the level of the umbilicus. The upper end of the left kidney is on a level with the eleventh dorsal spine behind, the right being a little lower (Figs. 30 and 31). The inferior extremity of the left gland is about two inches from the iliac crest, that of the right about one and a quarter inches. The hilus lies about two inches from the middle line, and is opposite to the first lumbar spine. The kidney has been reached by the finger when the entire hand has been introduced into the rectum, but the procedure has failed to prove of much use in diamosis. The anterior surface is but slightly covered by peritoneum, being only in contact with that membrane in such parts as are not in relation with the cellular tissue at the back of the colon and at the back of the duodenum or pancreas. The external border is more closely in connection with the peritoneum, while the posterior surface is quite devoid of that 327 Fig. 35. — View of the Kidneys, etc., from behind (Riidinger). a. Pharynx ; b, innominate artery ; c, suliclavian artery ; d, oesophasrus, with the aorta and thoracic duct on one side and the azyeos vein on the other; e, lunss ; /■, diaiihratrin : p, kidney; ft, on jieritoneuni, i)Oints to spermatic vessels crossed hy ureter: /, os iniioniinatuni al)ove sacro-iliac-syncbondr.'Sis ; j, psoas : k, gluteus medius ; I, gluteus maximus ; m, rectum and sup. baemorr- hoidai arter>\ 328 Surgical Applied Anatomy. [Chap. xvii. membrane (Figs. 34 and 35). Rwpture of tlie kidney is more often recovered from than is a Kke lesion of any other of the more commonly injured abdominal viscera. This depends upon its extensive non-peritoneal surface, whereby the extrava- sation of blood and urine that follows the accident is very often entirely extra-peritoneal. The gland may be readily wounded from behind or from the loin, without the peritoneum being injured. When the spine is much bent forwards, the kidney lies in the angle of the bend, at a part where the flexion of the column is the most acute. In extreme flexion, there- fore, of the spine it may be squeezed between the ilium and the lower ribs. Thus hsematuria is not uncommon after iiyuries to the back, associated with extreme bending of the spine forwards, as when a heavy weight falls upon the bowed shoulders. The kidney is embedded in a large quantity of loose fatty tissue, and suppuration extending in this tissue constitutes a perinephritic abscess. Such an abscess may be either due to disease of the kidney itself, to affections of the adjacent parts (spine, colon, etc.), or to injuries. The pus is at first in front of the quadratus lumborum, and then usually makes its way through that muscle or through the lumbar fascia. It then presents itself at the outer edge of the erector spinse, having passed between the adjacent borders of the external oblique and latissimus dorsi muscles. It may, however, spread into the iliac fossa, or extend into the pelvis along the loose connective tissue behind the descending colon and rectum, or open into the colon or bladder, or even into the lung. Most rarely of all does it perforate the peritoneum. Renal abscess usually opens upon the non-peritoneal surface of the gland. It may oi)en into the adjacent colon. In one case a renal abscess, due to stone, made its way from the right kidney into Chap. XVII.] The Kidney. 329 the pyloric end of the stomach, so that a communi- cation was establislied between those two organs. Movable kidney. — Tlie kidney is fixed in position mainly by the tension of the ]ieritoneum that passes over it, and that is connected with the fatty tissue supporting the gland. If this fatty tissue be absorbed for any reason, the kidney can be readily moved about and displaced in the subserous tissue ; the peritoneum at the same time becomes lax, and the gland by its own weight can drag still further upon it. Moreover, a laxity of the peritoneum from any cause may loosen the firm connections of the kidney and allow the organ to become more movable. Thus, the movable kidney is often met with in badly nourished subjects, and especially in those who have become emaciated by disease. It is far more common in women than in men. In the former sex, the influence of pregnancy ajipears to have especial effect, acting, probably, by dragging upon the peritoneum and by loosening its connections, as well as by inducing, after delivery, a general laxity of the abdominal walls. The movable kidney can, of course, only be moved within a segment of a circle whose radius corresponds to the length of the renal vessels, and its displacement is seldom considerable. There is a congenital form of movable kidney where the gland is suspended in a peritoneal fold of its own, the meso-nephron, and where the renal vessels are of undue lenajth. Such a kidney may be found near the anterior abdominal wall. One kidney may be very small, and the other unusually large. Both glands may be situated in the pelvis, or the two kidneys may be joined together by their lower ends across the middle line, forming a " horse-shoe kidney," with the concavity upwards. There may be only one large kidney ; and, lastly, cases are recorded where three kidneys have been found. 330 Surgical Applied Anatomy. [Chap. xvii. Operations on tlie kidney. — (1) Nephrotomy. Incision into the kidney for exploration, or the evacuation of pus. (2) Nej^hro-litliotomy. Incision into the gland for the removal of a calculus. (3) Nephrecto7ny. Removal of the entire organ. (4) Nejihrorapliy. The operation of securing a movable kidney in its normal position. In the first, second, and fourth operations, the kidney is reached through the loin by a transverse inctsion, such as is used in colotomy (page 315). In nephrectomy a like incision may be used, or, if more room be required, an oblique cut is made running downwards and forwards from the middle of the last rib. The capsule is incised and peeled ofi', the gland being removed from within its capsule. In some instances the last rib has been resected to obtain more space for the operation. This can be done without risk to the pleura. In one case the twelfth rib was rudimentary, and the eleventh rib was re- moved under the impression that it was the twelfth. The pleura was opened and death ensued. When the kidney is free from its capsule, the structures at the hilus are secured en Tnasse by a ligature. In removing large renal growths an abdominal incision is advised, the cut being made along the corresponding semilunar line, and on a level with the diseased mass. The abdominal operation of course involves an opening into the peritoneal cavity, but it has the advantages of greater ease and rapidity in performance. The ureters are strong tubes about fifteen inches long, with thick muscular walls, and are placed entirely behind the peritoneum. The average width is that of a goose-quill. The narrowest part of the tube is the portion within the bladder walls, and when renal calculi pass along the ui-eter they are often arrested at this point. The ureters permit of great distension, and in certain cases of gradual dilatation they have attained a width equal to that of the thumb and even Chap. XVII.] The Abdominal Nerves. 331 of the small intestine. Several cases are recorded of rupture of the ureter from external violence. When such an accident occurs a large urinary collection usually forms behind the peritoneum, which, leading to suppuration, will produce a fluctuating tumour beneath the parietes. The iicrvc isiipply of the abcloiiiilBal vi^^ccra. — Some account has already been given of these nerves and their communications (page 273). The abdominal viscera are mainly supplied by the sympathetic system through a series of remarkable plexuses. The most important of these is the solar, from which is more or less directly derived the nerve supply of the stomach, liverj spleen, kidneys, suprarenal capsules, pancreas, and such parts of the intestine as are in connection with the superior mesenteric artery. The solar plexus and its appendages receive the splanchnic nerves land some branches from the vagus, while com- munications from the phrenic go to the hepatic and suprarenal plexuses. It may be well understood that an impression brought to bear upon nerve centres of such extent and with such important relations would produce considerable effects. These effects we see in the profound collapse, vomiting, and other grave symptoms that attend severe injuries to the viscera j and especially to those that are the most directly asso- ciated with these large centres. The descending colon and sigmoid flexure are supplied by the inferior mesenteric plexus, a cord that has but an indirect connection with the solar plexus ; and this fact may serve to account for the less serious symptoms often seen in strangulation of the colon when compared with a like lesion of the small gut. The upper part of the colon, although supplied by the superior mesenteric plexus, is only supplied by that part of it that is most remote from the great centx'es, and it is a conspicuous fact that the nearer 332 Surgical Applied Anatomy. [Chap. xvii. the lesion is to the stomach the graver, other things being equal, are the nervous phenomena produced. It would appear that some lesion of these nerve plexuses is sometimes active in producing a remark- able pigmentation of the skin. This is seen in Addison's disease, a disease marked by a general bronzing of the surface, and usually associated with some disintegration of the suprarenal capsules. The very direct relation of these bodies to the solar plexus is well known. In pregnancy also, in abdominal tuberculosis, in cancer of the stomach, and in liver diseases, a pigmentation of the face is sometimes seen, that may in such instances be probably ascribed to a disturbance of the great abdominal nerve centres. In some diseases of the liver and stomach," sympa- thetic" pains are complained of between the shoulders 01- about the inferior angles of the scapulae. These parts are supplied with sensation by the fourth, fifth, and sixth dorsal nerves. The great splanchnic cord can probably explain the peculiar seat of these pains, since it is connected on the one hand with the plexuses that supply the stomach and liver, and on the other hand with these very dorsal nerves that are distributed about the lower interscapular space. Much discussion has taken place as to the cause of the " shoulder tip " pain often complained of in liver ail- ments. Some imagine that the pain is conducted along the hepatic plexus to the vagus, thence to the spinal accessory, and so to the point of the shoulder. Others trace it from the liver plexus to the phrenic, thence to the third and fourth cervical nerves (from whence the phrenic is in great part derived), and finally to those branches of these cervical trunks that go to the shoulder tip (the acromial branches). There would seem to be but little connection between a disease in the sigmoid flexure and a pain in the knee, yet in cases of cancer of the flexure, and in Chap. XVII.] The Abdominal Vessels. 333 instances where it has been distended with fseces, such a pain has been complained of. The pain is conveyed along the obturator nerve, which lies beneath the sigmoid flexure, and could be readily pressed upon by that gut when diseased. The blood-vessels of the abdomen. — Some of the visceral branches of the abdominal aorta are of large size, and would bleed very copiously if wounded. Thus, the cceliac axis, and the superior mesenteric artery, are as large as the common carotid ; the splenic, hepatic, and renal vessels are about the size of the brachial ; while the largest part of the inferior mesen- teric trunk has dimensions equal to those of the ulnar artery. Aneurisms of the aorta are especially apt to occur at the coeliac axis, that being a point where a number of large branches are abruptly given off, and where the course of the circulation undergoes in con- sequence a sudden deviation. When it is remembered that the lumbar glands lie about the vena cava and iliac veins, it will be understood that great enlargement of those bodies may cause oedema from pressure. A number of minute but most important anasto- moses exist between some of the visceral branches of the abdominal aorta, and certain of the vessels supplied to the abdominal parietes. These anasto- moses are situated behind the peritoneum, and mostly concern such viscera as have a fair surface uncovered by that membrane. The visceral branches that join the anastomoses are derived from the hepatic, renal, and suprarenal arteries, and from the vessels supplying the lower part of the duodenum, the pan- creas, the csecum, and the ascending and descending segments of the colon. The parietal vessels joining with the above are derived from the phrenic, lumbar, ilio-lumbar, lower intercostal, epigastric, and circum- flex iliac trunks. In a case detailed by Professor 334 Surgical Applied Anatomy. [Chap, xviii. Chiene (Journ. Anat. and Phys., vol. iii.) the coeliac axis and mesenteric vessels were plugged, but blood in sufficient amount to supply the viscera had reached the branches of these arteries through their parietal com- munications. This anastomosis gives an anatomical demonstration of the value of local blood-lettings and of counter-irritants in inflammatory affections of certain of the viscera, and also a scientific basis to the ancient practice of poulticing the loin and the iliac region in nephritis and in inflammation about the caecum. Cases have been recorded of communications between the external iliac vein and the portal vein. These have generally been effected by the deep epi- gastric vein joining with a pervious umbilical vein in the vicinity of the navel. Thoracic duct. — Some six cases of wound of this duct have been reported, the injury being usually a stab. In each case lymph and chyle in large quantities escaped from the wound. In one instance the duct is said to have been injured by a bullet that entered just below the left scapula, since from the wound in the integuments large quantities of lymph escaped freely. The duct has been found to have been obliterated, and that, too, without produc- ing any marked symptoms during life. CHAPTER XYIIL THE PELVIS AND PERINEUM. The mechanism of the pelvis. — Besides forming a cavity for certain viscera, a support for some abdominal organs, and a point for the attachment of the lower limb, and of many muscles, the pelvis Chap. XVIII.] The Pelvis. 335 serves to transmit the weight of the body both in the standing and sitting postures. The transmission is efi'ected through two arches, one available for the erect position, the other for the posture when sitting. The sacrum which supports the spinal column is the centre or keystone of both these arches. When stand- ing, the arch is represented by the sacrum, the sacro- iliac synchondroses, the acetabula, and the masses of bone extending between the two last-named points. If all other parts of the pelvis were to be cut away but these, the portions left would still be able to support the weight of the body, and would represent in its simplicity the arch through which that weight is transmitted. When sitting the arch is represented by the sacrum, the sacro-iliac synchondroses, the tubera ischii, and the strong masses of bone that extend between the two last-named parts. Morris terms these two arches the femoro-sacral and the ischio- sacral. On examining the innominate bone it will be seen that its thickest and strongest parts are such as are situate in the line of these. " When very con- siderable strength is requisite in an arch, it is continued into a ring so as to form a counter-arch, or what is called a tie is made to connect together the ends of the arch, and thus to prevent them from starting outwards. By these means a portion of the superincumbent weight is conveyed to the centre of the counter-arch, and borne in what is called the sine of the arch. The body and horizontal rami of the pubes form the tie or counter-arch of the femoro-sacral, and the united rami of the pubes and ischium the tie of the ischio-sacral arch. Thus the ties of both arches are united in front at the symphysis pubis, which, like the sacrum or keystone, is common to both arches This explains how it is that so much strain is made upon the symphysis when any increased weight has to be supported by the pelvis, as in pregnancy j 33 lymphatics of lower limb = deep set of glands. The lymphatics that accompany the obturator, gluteal, and sciatic arteries, and the deep vessels of the penis, pass to the pelvis and have no concern with the inguinal glands. One of the deep glands lies in the crural canal and upon the septum crurale. Being surrounded by dense structures, it is apt to cause great distress when inflamed, and great pain when the hip is moved. In some cases, by reflex disturbance, it has produced symptoms akin to those of strangulated hernia. Some branches of the anterior crural nerve lie over the inguinal lymph glands, and Sir B. Brodie reports a case in which these branches were stretched over two en- larged glands, like strings of a violin over its bridge, so that violent pain and convulsive movements were set up in the limb. Elephantiasis Arabum is more common in the lower limb than in any other part, and leads to an 396 Surgical Applied Anatomy. [Chap. xix. enormous increase in the size of the extremity (Co- chin or Barbadoes leg). Its pathology is intimately concerned with the crural lymphatics. "Elephantiasis appears to consist primarily in an inflammatory hyper- plasia of the cellular elements of the connective tissue, in connection with which (according to Yirchow) there is reason to believe that the roots of the lymphatic vessels are specially involved. Inflammatory over- growth of the elements of the lymphatic glands next ensues, with obstruction to the passage of lymph through them. Then this fluid stagnates in the lym- phatic vessels, which sometimes dilate even to their radicles in the cutaneous papillae, and accumulates in the interstices of the affected tissues, adding to their bulk, and at the same time stimulating them to over- growth .... In some cases of elephantiasis, especially those in which the genital organs or adjoin- ing parts of the thigh or abdomen are implicated, groups of vesicles appear here and there on the affected surface, which are really dilated lymphatic spaces, and which, on rupturing .... discharge consider- able quantities (sometimes several pints at a time) of lymjDh (Dr. Bristowe). The hip joint. — The hip joint is an articulation of considerable strength. This strength depends not only upon the shape of the articulating bones, which permits of a good ball and socket joint being formed, but also upon the powerful ligaments that connect them, and the muscular bands that directly support the capsule. These advantages, however, are to some extent counterbalanced by the immense leverage that can be brought to bear upon the femur, and the nu- merous strains and injuries to which the joint is subjected, as the sole connecting link between the trunk and the lower limb. The acetabulum is divided into an articular and a non-articular part. The former is of horse-shoe shape, Chap. XIX.] „ Hip Joint. 397 and varies from one inch to half an inch in width. The bone immediately above the articular area is very dense, and through it is transmitted the superin- cumbent weight of the trunk. The non-articular part corresponds to tlie area enclosed by the horse-shoe, and is made up of very thin bone. In spite of its thinness it is very rarely fractured by any violence that may drive the femur up against the pelvic bones, since no ordinary force can bring the head of the thigh-bone in contact with this segment of the os innominatum. Pelvic abscesses sometimes make their way into the hip joint through the non- articular part of the acetabulum, and an abscess in the hip joint may reach the pelvis by the same route. But both such circum- stances are rare. In some cases of destructive hip disease the acetabulum may separate into its three component parts. Up to the age of puberty these three bones are separated by the Y-sliaped cartilage. At puberty the cartilage begins to ossify, and by the eighteenth year the acetabulum is one continuous mass of bone. The breaking up of the acetabulum by disease, therefore, is only possible before that year. The manner in which the various movements at the hip are limited may be briefly expressed as follows. Flexion, when the knee is bent, is limited by the con- tact of the soft parts at the groin, and by some part of the ischiofemoral liojament ; when the knee is ex- tended the movement is limited by the hamstring muscles. Extension is limited by the ilio-femoral or Y ligament. Abduction by the pectineo-femoral ligament. Adduction of the flexed limb is limited by the ligamentum teres and ischio-femoral ligameiit, and of the extended limb by the outer fibres of the ilio-femoral ligament and upper part of the capsule. Rotation outvmrds is resisted by the ilio-femoral ligament, and especially by its inner part, during extension, and by the outer limb of that ligament and 398 Surgical Applied Anatomy. [Chap. xix. Ihe liframentum teres durinof flexion. Rotation inwards is limited during extension by the ilio-femoral ligament, and during flexion by the ischio-femoral ligament and inner part of the capsule. Hip joint disease. — Owing to its deep position and its thick covering of soft parts, this articulation is able to escape, to a great extent, those severer injuries that are capable of producing acute inflammation in other joints. Acute synovitis is indeed quite rare in the hip, and the ordinary disease of the part is of a dis- tinctly chronic character. It follows also, from the deep position of the articulation, that pus, when it is formed in connection with disease, remains pent up, and is long before it reaches the surface. Suppuration in this region, therefore, is often very destructive. When efiusion takes place into the joint, the swelling incident thereto will first show itself in those parts where the hip capsule is the most thin. The thinnest parts of the capsule are in front and behind ; in front, in the triangular interval between the inner edge of the Y ligament and the pectineo-femoral ligament, and behind, at the posterior and lower part of the capsule. It is over these two districts that the swelling first declares itself in cases of effusion into the joint, and as these parts are readily accessible to pressure, it follows that they correspond also to the regions where tenderness is most marked and is earliest detected. In chronic hip disease, certain false positions are assumed by the affected limb, the meaning of which it is important to appreciate. These positions may be arranged as follows, according, as nearly as possible, to their order of appearing. (1) The thigh is flexed, abducted, and a little everted ; and associated, with this there is (2) apparent hmgtlicning of the limb and (3) lordosis of the spine ; (4^ the thigh is abducted and inverted, and Chap. XIX.] Hip Joint. 399 incident to this there is ( 5) apparent shortening of tlie limh ; (G) there is real shortening of the limb. 1. The first position depends upon the effusion into the joint. If tiiiid be forcibly injected into a hip joint the thigh becomes flexed, abducted, and a little everted. In other words, the articulation holds the most fluid when the limb is in this position, and the patient places it there to relieve pain by reducing the tension within the capsule to a minimum. Flexion is the most marked feature in this position. Its eff'ect is pronounced. It relaxes the main part of the Y ligament, which, when the limb is straight, is drawn as an unyielding band across the front of the joint. Abduction relaxes the outer limb of this ligament, and the eversion slightly relaxes the inner limb. The latter movement is the least marked, since eversion, even in the flexed position of the joint, is resisted by the outer pai-t of the Y liga- ment. Any but a moderate degi-ee of abduction would be limited by the pectineo-femoral ligament, especially as that band is rendered most tense when abduction is combined with flexion and rotation outwards. 2. The apparent lengthening is due to the tilting down of the pelvis on the diseased side, and is the result of the patient's attemjits to overcome the effects of the position just described. The limb is shortened by flexion and abduction, and to bring the foot again to the ground and to restore the natural parallelism of the limbs, the pelvis has to be tilted do\^ai on the affected side. Thus, an apparent lengthening of the limb is produced, whicli is noticeable when the patient lies upon a bed, and the abduction is made to entirely disa]">pear. Some real lengthening of the limb may be produced in this disease by the effusion into the joint separating the femur from the acetabulum, but it must be so slight that it is doubtful if it could be ap- preciated. By forcible injection into the joint Braune 400 Surgical Applied Anatomy. [Chap. xix. could only separate the articulating sui'faces about one-fifth of an inch. 3. The lordosis, or curving forwards of the spine, occurs in the dorso-lumhar region. It depends upon the flexion of the limb, and is the result of an attempt to con- ceal that false posi- tion, or at least to minimise its incon- veniences (Fig. 38). When the thigh is flexed at the hip by disease, the lower limb can be made to appear straight by simply bending the spine forwards in the dorso - lumbar region without effecting the least movement at the disordered joint. In- deed, the movement proper to the hip is in this case transferred to the spine. A patient with a flexed hip as the result of disease can lie on his back in bed, with both limbs apparently perfectly straight, he having concealed the flexion, as it were, by producing a lordosis of the spine. If the lordosis be corrected, and the spine be made straight again, then the flexion of the hip reappears, although all the time the hip joint has been absolutely rigid. This lordosis generally appears a little late in the disease, and after the limb has become more or less fixed in the false positions by contraction of the surrounding muscles. Fig. 38.— Diagram to show the Mode of Production of Lordosis in Hij) Disease. A, Femur flexed at liip, pelvis (represented l)y tbe dotted line) straight, and spine noriual. b, Tlie flexion concealed or overcome hy lordosis of the spine; the pelvis rendered oblique. Chap. XIX.] The Hip Joint. 40 j 4. Sooner or later, in hip disease, the thigh becomes aclducted and inverted, while it still remains flexed. This position has been variously accounted for. According to one theory, it is due to softening and yielding of some parts of the inflamed capsule. This view is set forth by Mr. Barker, in his admirable monograph on joint disease in Holmes' " System of Surgery," in the following words : " As the inflamed capsule commences to soften, its weakest part yields first, i.e., the posterior inferior This now admits of more flexion still. . . . The hori- zontal posterior fibres, which in the distended condition of the capsule help in the eversion, are the next to stretch, admitting of inversion, which is now the more possible, as the Y is relaxed by flexion, and its inner limb has no strain to be taken off by eversion. Finally, the upper and outer anterior fibres yield, and adduction then takes place." This explanation is a little unsatisfactory ; and it is more probable that this false position, and especially the adduction, depends upon muscular action. The muscles about the joint are in a state of irritability. They are contracted by a reflex action that starts from the inflamed articulation, and since the adductor muscles are supplied almost solely by tlie obturator nerve, it is not unreasonable to expect them to be especially disturbed if the large share that the obturator nerve takes in the supply of the hip be borne in mind. The adductors are also rotators outwards, but this latter movement would be resisted by the strong outer limb of the Y ligament, as well as by the ligamentum teres, both of which are rendered tense by rotation outwards during flexion. The whole matter, however, requires further investigation. 5. Apparent shortening of the limb is due to tilting up of the pelvis on the diseased side, and bears the same relation to adduction that apparent A A 402 Surgical Applied Anatomy. [Chap. xix. lengthening bears to abduction. To overcome the adduction, and to restore the natural parallelism of the limbs, the patient tilts up one side of his pelvis (Fig. 39). It thus happens that a patient with his femur (7, Fig, 39. — A, Parts in Normal Position, b, Femur Adducted. c, The Adduction Corrected by Tilting up the Pelvis. ac. Line of pelvis; a&, liml) on diseased side; cd, liml) on sound side; e, tlie spine. It will be found that in Figs, b and c, the angle at a is the sameiu the two cases. flexed and adducted by disease may lie in bed with both limbs quite straight and parallel, but with one limb obviously shorter than the other. The flexion in such a case is concealed by lordosis, and the adduction Chap. XIX,] The Hir Joint. 403 by the tilting of the pelvis. In some cases of simul- taneous disease in botli hip joints that has been in- differently treated, both thighs may remain adducted. The limbs are unable, of course, to remedy their posi- tion by the usual means, when the disease is double, and consequently one limb is crossed in front of the other, and the peculiar mode of progression known as " cross-legged progression " is produced. 6. The real shortening depends upon destructive chan2:es in the head of the bone, or to dislocation of the partly-disintegrated head on to the dorsum ilii, through yielding of the softened capsule and the crumbling away of the upper and posterior margin of the acetabulum. When hip disease commences in bone it usually involves the epiphyseal line that unites the head of the femur to the neck. This line is wholly within the joint, and the epiphysis that forms the head unites with the rest of the bone about the eighteenth or nineteenth year. When the bone is primarily involved the posi- tion of flexion and abduction with e version may not be observed at all, there being no effusion at first into the joint. In such cases the limb becomes at once flexed and adducted, and this posture is probably due solely to muscular spasm, and to an attempt to prevent the head of the femur from pressing against the acetabulum, and so causing pain. It is well known that patients with hip disease often complain of pain in the knee. This referred pain may be so marked as to entirely withdraw attention from the true seat of disease. Thus I once had a child sent to my out-patient department with a sound knee carefully secured in splints, but without any appliance to the hip, which was the seat of a somewhat active inflammation. This referred pain is easy to understand, since the two joints are supplied 404 Surgical Applied Anatomy. [Chap. xix. by branches of the same nerves. In the hip, branches from the (1) anterior crural enter at the front of the capsule ; (2) branches from the obturator at the lower and inner part of the capsule; and (3) branches from the sacral plexus and sciatic nerve at the posterior part of the joint. In the knee, branches from the (1) anterior crural (nerves to vasti) enter at the front of the capsule; (2) branches from the obturator at the posterior part of the capsule; and (3) branches from the internal and external popliteal divisions of the great sciatic nerve at the lateral and hinder aspects of the joint. Pain, therefore, in the front of the knee, on one or both sides of the patella, has probably been re- ferred along the anterior crural nerve, and pain at the back of the joint along the obturator or sciatic nerves. In hysterical individuals joint disease may be imitated by certain local nervous phenomena, the articulation itself being quite free from structural change. This affection most commonly shows itself in the hip or knee, and the "hysterical hip," or "hysterical knee," takes a prominent place in the symptomatology of hysteria. It is not quite easy to understand why these two large joints should be so frequently selected for the mimicry of disease. Hilton has endeavoured to explain the fact upon anatomical grounds, having reference to the nerve supply of these joints in relation to the nerve supply of the uterus. The uterus is mainly supplied by an offshoot from the hypogastric plexus, and by the third and fourth sacral nerves. Now, the hyjoogastric plexus contains fila- ments derived from the lower lumbar nerves ; and from the same trunks two nerves to the hip and knee (the anterior crural and obturator) are in great part derived. The great sciatic also contains a large portion of the third sacral nerve. This common Chap. XIX.] The Upper End of JFemur. 405 origin of the joint and the uterine nerves forms the basis of Hilton's explanation of the- relative fi-equency of hysterical disease in the large articulations of the lower limb. The explanation, however, is unsatisfac- tory, since the uterus receives many of its nerves from the ovarian plexus, and the theory is founded upon the unwarranted supposition that all hysterical dis- orders are associated with some affection of the uterus or its appendages. Fractures of the upper end of the femur may be divided into (1) fractures of the neck wholly within the capsule ; (2) fractures of the base of the neck not wholly within the capsule ; (3) fractures of the base of the neck involving the great trochanter ; (4) separations of epiphyses. It must be scarcely possible, apart from gunshot injuries, to fracture the neck of the femur by direct violence, owing to the depth at which the bone is placed, and the manner in which it is protected by the surrounding muscles. The violence, therefore, that causes the lesion is nearly always applied indirectly to the bone, as by a fall upon the feet or great trochanter, or by a sudden wrench of the lower limb. M. Kodet, by a series of experiments, concludes that the situation of the fracture can be predicated by a knowledge of the direction in which the violence has acted. " Thus, a force acting vertically, as in falling on the feet or knees, will produce an oblique intracapsular fracture ; a force acting from before backwards, a transverse intracapsular fracture ; one from behind forwards, a fracture partly within and partly without the capsule, and a force applied transversely, a fracture entirely without the capsule." (Quoted by Henry Morris; Holmes' "System of Surgery.") 1. The true intracapsular fracture may involve any part of the cervix within the joint, but is most 40 6 Surgical Applied Anatomy. [Chap. xix. usually found near the line of junction of the head with the neck. This fracture is most common in the old, in whom it may be produced by very slight degrees of violence. The liability of the aged to this lesion is explained upon the following grounds. The angle between the neck and shaft of the femur, which will be about 130° in a child, tends to diminish as age advances, so that in the old it is commonly about 125°. In certain, aged subjects, as a result probably of gross degenerative changes, this angle may be reduced to a right angle. This diminution of the angle certainly increases the risk of fracture of the neck of the bone. There is often also, in advanced life, much fatty degeneration of the cancellous tissue of the cervix with thinning of the compact layer. Dr. Merkel (Amer. Journ. Med. Sc, 1874) also asserts that in old persons there is an absorption of that process of the cortical substance which runs on the anterior part of the neck between the lesser trochanter and the under part of the head. This process he calls the " calcar femorale," and maintains that it occupies the situation at which the greatest pressure falls when the body is erect. These fractures are but rarely impacted ; but when impacted, the lower fragment, represented by the relatively small and compact neck, is driven into the larger and more cancellous fragment made up of the head of the bone. The fracture may be subperiosteal, or the fragments may be held together by the reflected portion of the capsule. These reflected fibres pass along the neck of the bone from the attachment of the capsule at the femur to a point on the cervix much nearer to the head. " These reflected fibres occur at three places, one corresponding in position to the middle of the ilio-femoral ligament, another to the pectineo-femoral, and the third on the upper and back part of the neck " (Henry Morris). Fractures of this Chap. XIX.] The Upper End of Femur. 407 part very rarely indeed unite by bone. Blood is brought to the head of the bone by the cervix, the reflected parts of the capsule, and the ligamentum teres. When the first two sources of blood supply are cut off by the fracture the third does not appear to be suflicient to allow of great reparative changes taking place in the upper fragment. The fractures that heal by bone are probably either impacted, or subperiosteal, or not wholly intracapsular. 2. With regard to fractures at the base of the neck, it must be remembered that a wholly extra- capsular fracture of the neck of the femur is an anatomical impossibility. If the fracture is wholly without the capsule, then it must involve a part of the femoral shaft, and cannot be entirely through the cer\dx. In the front of the bone the capsule is attached to the femur along a part of the inter- trochanteric line, and strictly follows the line of junction between the cervix and the shaft. Behind, the capsule is inserted into the neck some half of an inch in front of the posterior inter-trochanteric line. It is therefore possible for a fracture of the neck to be extracapsular behind, but not in front, and many of these lesions at the base of the neck have this relation to the capsule. The Y ligament is so thick, being in one place about a quarter of an inch in thickness, that a fracture involving the base of the cervix may run between its fibres at their attachment, and be neither extra- nor intra-capsular. When fractures at the junction of the neck and shaft are impacted, the upper fragment, represented by the compact and relatively small cervix, is driven into the cancellous tissue about the great trochanter and upper end of the shaft. As a result of this impaction the trochanter may be split up, and the bones may become free again through the extent of thi* splinteriug. 4o8 Surgical Applied Ajvatomv. [Chap. xix. With regard to the symptoiMS of a fracture of the neclt of the femBir, the following may be noticed : (a) The swelling often observed in the front of the limb, just below Poupart's ligament, is due either to effusion of blood into the joint, or to pro- jection of the fragments against the front of the capsule ; (6) the shortening is brought about by the glutei, the hamstrings, the tensor vaginae femoris, the rectus, sartorius, and ilio-psoas, the adductors, gracilis and pectineus ; (c) the eversion, or rotation out- wards of the limb, is mainly due to two causes : (1) The weight of the limb, which causes it to roll outwards, as is seen in persons insensible or asleep, the line of gravity passing through the outer part of the thigh ; (2) the fact that the compact tissue on the posterior aspect of the neck is much more fragile than that on the anterior aspect. Thus the cervix is often more extensively fractured behind than in front, or the fracture may be impacted behind but not in front, and in either case the limb will tend to become everted. As a third cause may be mentioned the action of the ilio - psoas, the adductor and pectineus muscles, and of the small rotators muscles, all of which will tend to roll the femur outwards. 3. Fracture of the base of the neck, involving the great trochanter. In this lesion the head, the cervix, and a part of the great trochanter, are sepa- rated from the shaft and rest of the trochanter. 4. Separation of epiphyses. There are three epiphyses in the upper end of the femur, one for the head, which unites between eighteen and nineteen ; one for the lesser trochanter, which unites about seventeen ; and one for the greater trochanter, which unites about eighteen. The neck is formed by an extension of ossification from the shaft. A few cases are recorded where it is supposed that the cajmt fcinoris was separated at the epiphyseal line by Chap. XIX.] Dislocations of the Hip. 409 violence, but the accident is, I believe, illustrated by no actual specimens. Mr. Henry Morris has collected five cases of separation of the epiphysis of the great trochanter. This separation, if complete, could hardly avoid being intracapsular in part, since the capsule is attached to the anterior superior angle of the trochanter itself. Dislocations of the hip. — These injuries are comparatively rare, on account of the great strength of the articulation, and when they occur in a healthy joint are always the result of a considerable degree of violence. A dislocation of the hip may be congenital, or may be spontaneously produceel by muscular efforts, as shown in a few rare cases, or may be the result of disease of the articulation. We are", how- ever, now concerned only with "regular" dislocations, the result of violence. Varieties. — The head of the bone may be found displaced in four directions, producing the four regular dislocations of the hip. In two the head of the femur is posterior to a line drawn vertically through the acetabulum, and in the other two it is found anterior to that line. (1) Backwards and upwards. Head rests upon ileum, just above and behind acetabulum. The ^'■dis- location upon the dorsum ilh." (2) Backwards. Head rests upon ischium, and, as a rule, about on a level with the ischial spine. The " dislocatio7i into the sciatic notch." (3) Forwards and downwards. Head rests on thyroid foramen. The " obturator or thyroid dislocation.'' (4) Forwards and upwards. Head rests upon the body of the pubes, close to its junction with the ileum. The ""dislocation upon the pubes.'^ The above arrangement represents also the order of frequency of these luxations. No. 1 being the most common dislocation of this part, and No. 4 the most rare. 41 o Surgical Applied Anatomy. [Chap. xix. Oeiieral facts. — In all these dislocations of the hip, (a) the luxation occurs when the limb is in the position of abduction ; (h) the rent in the capsule is always at its posterior and lower part ; (c) the head of the bone always passes at first more or less directly downwards ; (d) the Y ligament is untorn, while the ligamentum teres is ruptured. {ci) It is maintained that in all luxations at the hip, the joelvis and femur are in the mutual position of abduction of the latter at the time of the accident. The direction of the neck of the femur and of the acetabulum, and the position of the cotyloid notch, all favour dislocation in the abducted posture. The lower and inner part of the acetabulum is very shallow, and the lower and posterior part of the capsule is very thin. In abduction, the head of the bone is brought to the shallow part of the acetabulum ; it moves more than half out of that cavity ; it is supported only by the thin weak part of the capsule, and its further movement in the direction of abduction is limited only by the pectineo- femoral ligament, a somewhat feeble band. In abduction the round ligament is slack, and in abduction with flexion both the Y ligament and the ischio-femoral ligaments are also relaxed. In the position of abduction, therefore, no great degree of force may be required to thrust the head of the bone through the lower and posterior part of the capsule, and displace it downwards. (6) The above being allowed, it will be understood that the rent in the capsule is always at its posterior and lower parts. " Generally the rupture is jagged and irregular, but will be found to extend more or less directly from near the shallow rim of the aceta- bulum, across the thin portion of the capsule to the femur near the small trochanter, and then to run along the back of the ligament close to its attachment to the neck of the bono " (Henry Morris). Chap. XIX.] Dislocations of the Hip. 411 (c) If the position of the limb at the time of the accideut be considered, it will be seen that the femur will in every case be displaced downwards. There is, indeed, but one primary dislocation of the hip, a luxation downwards. The four forms given above are all secondary, the bone having in each instance first passed downwards before it moved to any of the positions indicated. This point has been ably demonstrated by jNtr. Henry Morris, whose account of the anatomy of hip dislocations is most valu- able. The head having left the acetabulum, its ultimate destination will depend upon the character of the dislocating force. "If the limb be flexed on the pehds, and rotated inwards, or the pelvis be corre- spondingly moved on the thigh at the moment of displacement, the head of the femur will take a backward course, and rest on the dorsum ilii or some part of the ischium. On the other hand, extension and outward rotation will cause the head of the bone to travel upwards and forwards, and what is called a dislocation on to the pubis will occur If the dislocation is neither accompanied nor followed by rotation, or fixed flexion or extension, the head of the femur will remain below the acetabulum, and will occupy the foramen ovale, if it takes a slightly forward direction in its descent, or some position near the tuberosity of the ischium if it leaves its socket in a backward and downward direction " (Henry Morris). (rf) The Y ligament is never torn in any "regular" dislocation. It is saved by its great density, aud the circumstance that it is probably more or less relaxed at the time of the luxation. The method of reducinor these dislocations by mani2)ulation depends for its success mainly upon the integrity of the Y ligament, which acts as the fulcrum to a lever of which the shaft of tlie femur is the lona: arm, and the neck the short. In the backward luxations the head is behind 412 Surgical Applied Anatomy. [Chap. xix. having general the Y ligament, and in the forward displacements in front of it. The anatomy of eacli form. — Nos. 1 and 2. The, dislocations backwards. Here the femoral head, having been displaced in the way indicated, is carried towards the dorsum or sciatic notch by the glutei, hamstring, and ad- ductor muscles. The bone taken a direction back- wards, the height to which it ascends de- pends mainly upon the nature of the dislocating force, and also uj^on the extent of the rup- ture in the caj^sule, and the laceration of the obturator internus tendon and other small external rotators. The dorsal disloca- tion is, therefore, a more advanced grade of the sciatic. The more extreme the flexion and inward rotation at the time of tlie accident the more likely is the dislocation to be sciatic. More moderate flexion and inward rotation will produce a luxation upon the dorsum. In the dorsal luxation the head is above the obturator internus tendon, while in the sciatic form it is below it (Bigelow). Morris has been able to find but one case of direct dislocation of the femur backwards on to the ischium. In every instance it passes first in a downward direction, and then backwards. Fig, 40. — Dislocation npon the Dorsum ilii (Bigelow). Chap. XIX.] Dislocations of the Hip. 413 Bigelow states that there is no evidence to show tliat the head of the femur has ever been actually displaced into the sciatic notch. In these backward dislocations the ilio- psoas muscle is greatly stretched. The quadratus femoris, the obturators, the gcmelli, and the pyriformis ai-e more or less lacerated. The pectineus is often torn, and the glutei muscles even may be ruptured in part. The gr(^at sciatic nerve may be compressed between the femoral neck and the rotator muscles, or between the head of the bone and the tuber ischii. In both of the backward lux- ations there is shor- tening, due to the circumstance that the line between the an- terior superior spine and the femoral condyles is lessened l)y the displacement ng. 41, -Obturator or Thyroid Disloca- back wards of the tion (Bigelow). bone, with the addi- tional shortening in the dorsal dislocation brought about by the passing of the femoral head above the level of the acetabulum. The adduction and in- version in the main depend upon the position of the head and cervix, which must follow the plane of the bone upon which they lie. This position is maintained by the tense Y ligament. The damage done to the chief external rotators places them also liors de combat. The flexion is due to 414 Surgical Applied Ana tomy. [chap. xix. the tension of tlie Y ligament, and of the ilio-psoas muscle. Nos. 2 and 3. The dislocations forwards. If the head after leaving the acetabulum simply moves a little forwards along the inner edge of the socket, the thyroid lux- ation is produced. If it goes farther and moves upwards, the pubic displacement will result. The latter dis- location is therefore but an advanced form of the first - named. Whether the head will remain in the thyroid foramen or ascend on to the pubes depends on whether extension and rotation outwards accompanies the dis- placement. If these occur the pubic form is produced. In these injuries the pectineus, gracilis, and adductors will be more or less torn, while the ilio-psoas, glutei, and pyriform muscles are much stretched. The obturator nerve may be stretched or torn, and in the pubic luxation the anterior crural nerve may be involved. The abduction and eversion of the limb noticed in these luxations depend partly upon the position of the head of the bone, fixed more or less by the Y ligament, and partly upon the action of the gluteal muscles and some of the small external rotators, which are tightly stretched, The flexion of the Fig. 42.— Dislocation upon the Pubes (Bigelow). Chap. XIX.] Dislocations of the Hit. 415 limb is mainly duo to the stretching of the ilio- psoas muscle. In the thjrroicl luxation tlie extremity is said to bo lengthened. This lengthening is, however, apparent, and is due to the tilting down of the pelvis on the injured side. In the pubic dislocation there is shortening, the head being carried above the ace- tabular level. Of the modes of reducing these dislocations by manipulation little can be said here. The more usual proceedings may be briefly summarised as follows : — First — Flex the thigh in the adducted position in luxations Nos. 1 and 2. ( To relax the Flex the thigh in the abducted ( Y ligament, position in luxations Nos. 3 and 4. Secondly. — Circumduct out in^ Tobring back the head Nos. 1 and 2. 'to the rent in the cap- Circumduct in in C sule by the same route Nos. 3 and 4. ) that it has escaped. Thirdly. — Extend in all cases. To induce the head to again enter the acetabulum. In reducing dislocations of the hip it may be noted that the internal condyle of the femur faces in nearly the same direction as the head of the bone. In amputatioii at the hip-joint by long anterior and short posterior flaps the following parts are divided. In the face of the anterior flap will be seen sections of the tensor vaginae femoris, rectus, part of the vasti, the adductors longus and brevis, and the gracilis. Close to the acetabulum in front are sections of the ilio-psoas and pectineus muscles, and behind and to the inner side the obturator externus. In this flap also, close to the angle between it and the posterior flap, are small portions of the glutei to the 4i6 Surgical Applied Anatomv. [Chap. xix. outer side of the hip, and of the adductor magnus to the inner side. The cut end of the sartorius is found on the lower edge of the flap. The femoral and Fig. 43. — Amputation at Hij) Joint (Agatz). a. Head of femur : h, acetaljiiluin ; c, part of capsular ligament; iirsai of any magnitude about the Chap. XXIII.] The Ankle and Fuct. 469 foot, save one betwe'en the tendo Acliillis and os calcis, and another over the nietatarso-phalangeal joint of the great toe. Tlie first-named bursa lises up about half an inch above the os calcis, and bulges out on either side of the tendon. When inflamed it may produce symptoms like those of ankle-joint disease, and when suppurating may lead to caries of the OS calcis. The enlargement of the bursa over the metatarso-phalangeal joint of the great toe consti- tutes a bunion. This condition is generally brought about by improperly-shaped boots, which force the great toe outwards, place it obliquely to the long axis of the foot (with which it should be parallel), and render the metatarsal joint very prominent. The result of this deformity is a great weakening of the toe and adjacent part of the foot, a lengthening of the internal lateral ligament of the little joint, and a displacement outwards of the tendon of the extensor proprius pollicis. Bursse are often de- veloped over the malleoli in tailors, and especially over the external process, the part most pressed upon when sitting cross legged. " In club-foot, bursse are found over any points that are exposed to undue pressure. The tendons about the ankle are not infrequently ruptured by violence. Those that most frequently are so injured are the tendo Achillis, and the tendons of the tibialis posticus and long and short peroneal muscles. The tendo Achillis usually breaks at a point about one and a half inches above its insertion, where it becomes narrowed and its fibres are col- lected into a very definite bundle. In some forms of violence the synovial and fibrous sheaths that bind down a tendon may be ruptured and it be allowed to become displaced. This has hap- pened to the tibialis posticus and peroneal muscles. In each instance the dislocated structure comes forwards 47 o Surgical Applied Anatomy. [Chap. xxiii. upon or in front of tlie malleolus. No tendon in the body is so frequently displaced as is that of the peroneus longus. The tendons about the ankle are frequently divided by operation. The tendo Achillis is usually cut about one inch above its insertion, the knife being entered from the inner side to avoid the posterior tibial vessels. The tibialis posticus tendon is, as a rule, divided just above the base of the inner malleolus. There is, however, enough room between the annular ligament and the scaphoid bone to cut it on the side of the foot. The anterior tibial tendon may be divided readily either in front of the ankle or at its insertion into the internal cuneiform bone. Slood-vessels. — The lines of the various arteries have been already indicated. Wounds of the plantar arch are serious, on account of the depth at which the external plantar artery lies, and the impossibility of reaching the vessel without making a large wound in the sole that would open up important districts of connective tissue, and do damage to tendons and nerves. The arch is formed by the junction of the external plantar artery with the dorsal artery of the foot, a continuation of the anterior tibial vessel. In cases, however, of bleeding from the arch ligature of both the posterior and anterior tibial vessels at or just above the ankle, would not necessarily arrest the haemorrhage. After ligature of these vessels blood Avould still be brought in- directly to the arch by means of the peroneal artery. By its anterior peroneal branch this vessel com- municates with the external malleolar branch of the anterior tibial artery, and with the tarsal branch of tlie dorsalis pedis. By its terminal branch it com- municates with the two last-named vessels, and also with the internal calcaneal branches of the external Chap. XXIII.] The Ankle and Foot. 471 plantar artery. As a matter of practice, however, elevation of the limb, together with pressure upon the wounded point, :ind compression of the main artery, are sufficient to check most haemorrhages from the plantar arch. It must be remembered that this arch can be wounded by penetrating woimds intlicted upon the dorsum of the foot ; and Dr. Delorme has shown how readily various parts of the arch may be ligatured from the dorsum after portions of one or other of the meta- tarsal bones have been removed Thus by resecting the upper part of the shaft of the fourth metatarsal bone in one case, the main part of the shaft of the third bone in another, and the upper part of the shaft of the second bone in a third instance, he has been enabled to expose and ligature the greater part of the plantar arch from the dorsal aspect of the foot. The dorsalis pedis artery, from its superficial position and its close contact with the bones of the foot, is frequently divided in wounds, and ruptured in severe contusions. The posterior tibial artery at the ankle is well protected by the projecting malleolus, the dense annular ligament, and the tendons that run by its side. The superficial veins of the foot, like those of the hand, are found mainly upon the dorsum of the member. The sole, as a part exposed to pressure, is singularly free from them. About the malleoli, and especially about the inner process, these veins form a considerable plexus. Hence it is that appliances that fit tightly around the ankle are apt to produce cedema and pain in the parts beyond. The dull pain in the feet that is often caused by tight elastic-side boots is probably due to the same cause. It will be understood that wounds and suppurations about the dorsum of the foot are more apt to be attended by 472 Surgical Applied ANATOMy. LCh:.p. xxiii. phlebitis tliau are like lesions when situated upon the sole. Venesection is sometimes performed in the foot, the vein opened being either one of those forming the dorsal plexus, or more usually the internal saphenous vein just above the malleolus. The vessels are rendered conspicuous by placing the foot in hot water, and then applying a constricting band around the leg. The lympliatics form a very fine and elaborate plexus in the coverings of the sole, from which vessels aiise that reach the borders and dorsum of the foot, and principally the inner border. The main lymph vessels of the part are found upon the dorsum and about the radicles of the two saphenous veins. Those on the inner side of the foot are by far the more numerous ; they follow pretty generally the course of the internal saphenous vein, and end in the inguinal glands. The external vessels pass up along the outer ankle and outer side of the leg. The bulk of them pass obliquely across the ham to join the inner set above the knee ; others reach the inner set by crossing the front of the tibia, while a few follow the short saphenous vein and end in the popliteal glands. Thus, so far as the foot is concerned, lymphangitis is more common after wounds of the dorsum than after wounds of the sole, although in the latter locality the frequent retention of pus beneath the dense fascia greatly favours lymphatic inflammations. Since many vessels cross the shin on their way from the outer to the inner set of vessels, it will be seen that abrasions, etc., of that part of the limb are very apt to be followed by inflammation of the lymph canals, A lesion on the inner side of the foot, and most lesions on the dorsum, will be associated with enlargement of the inguinal glands ; wliile a _ like mischief on the outer border of the foot may affect either the inguinal or the popliteal chain of glands. Chap. XXIII.] The Ankle and Foot. 473 The ankle-joint is a very powerful articulation, its strength being derived not only from the shape of its component bones, but also from tlie unyielding ligaments and many tendons that are bound about it like straps. Of the ligaments, the two lateral are very strong, and have an extensive hold upon the foot. The anterior and posterior are extremely thin and insignificant, although the latter is supported by the tendon of the flexor longus pollicis, which crosses it. When etiusion takes place into the joint, it first shows itself in front, beneath the extensor tendons, and just in front of the lateral ligaments. This is due to the feebleness of the anterior liga- ment and the extent and looseness of the synovial sac in relation with that structure. More extensive effusions cause a bulging behind through yielding of the thin posterior part of the capsule, and fluctua- tion can then be obtained on either side of the tendo Achillis. In no ordinary case can fluctuation be detected distinctly beneath the unyielding lateral ligaments. Moreover, the loose synovial sac of the ankle-joint extends both in front and behind beyond the limits of the articulation, while, at the sides, it is strictly limited to the joint surfaces. The ankle is a perfect hinge-joint, and permits only of flexion and extension. The very slightest amount of lateral movement is allowed in extreme extension, when the narrower, or hinder, part of the astragalus is brought into contact with the widest, or anterior, part of the tibio-fibular arch. When obvious lateral movement exists at the ankle, the joint must be the seat of either injury or disease, and it is important not to mistake the lateral movements permitted between certain of the tarsal bones for movements at the ankle-joint. Flexion is limited by the posterior and middle parts of the internal ligament, by the poste- rior part of the external ligament, by the posterior 474 Surgical Applied Anatomy. [Chap. xxiii. ligament, and by the contact of the astragalus with the tibia. Extension is limited by the anterior fibres of the inner ligament, the anterior and middle parts of the outer ligament, by the anterior part of the capsule, and the contact of the astragalus with the tibia. Owing to its exposed position, this joint is very liable to become inflamed from injury or other ex- ternal causes. When inflamed, no distortion is, as a rule, produced, the foot remaining at right angles with the leg. It would appear that this position is due to the circumstance that the flexor and extensor muscles about balance one another, and it does not seem that the capacity of the joint is affected by the posture of the foot. The synovial cavity of the ankle is in communication with the inferior tibio- fibular articulation. In connection with the subject of " referred pains," it should be remembered that the nerves supplying the ankle-joint bring that articulation into relation with two great plexuses, with the lumbar plexus through the internal saphenous nerve, and with the sacral plexus through the external division of the anterior tibial nerve. Dislocations at the ankle-joint. — The foot may be dislocated at the ankle in five directions, which, placed in order of frequency, are, outwards, inwards, backwards, forwards, and upwards between the tibia and fibula. These dislocations are nearly always associated with fracture of either the tibia or fibula, or of both bones. 1. The lateral dislocations : Outwards, inwards. These luxations differ somewhat from those met with in other joints. In the great majority of cases they consist of a lateral twisting of the foot, of such a kind that the astragalus is rotated beneath the tibio-fibular arch. There is no great removal of the Chap, xxiii] The Ankle and Foot. 475 upper surface of "the astragalus from that of the tibia, but rather is one or other edge of the former bone brought in contact with the horizontal articular surface of the latter. Although mucli deformity is jn-oduced, the actual separation of the foot from the leg is not considerable. In some rare cases a true lateral dislocation in the horizontal direction has been met with. These injuries are due to sudden and violent twistings of the foot, and are in nearly every instance associated with fractures of the tibia or tibula. Tlie luxation outwards is due to forcible eversion of the foot, the luxation inwards to violent inversion. It is of interest, in the first place, to note the re- lation of the fibula to injuries at the ankle-joint, especially as a fracture of the lower end of the shaft of that bone may follow alike upon both inversion and eversion of the foot. The lower three or four inches of the fibula may be considered to form a lever of the first kind (Fig. 54, a). The fulcrum is at the inferior tibio-fibular articulation, one arm of the lever is the malleolus below that joint, while the other arm may be regarded as formed by the lower two or three inches of the shaft of the bone, Now the lower ends of the tibia and fibula are bound together by very powerful ligaments, viz., the anterior and posterior tibio-fibular, the transverse, and the inferior interosseous. I would venture to parti- cularly insist that in no ordinary lesion about the ankle, whether fracture or dislocation, do these liga- ments give way. If they should yield, then an anomalous form of fracture or luxation will be pro- duced. In forcible eversion of the foot, the internal lateral ligament becomes stretched and tears, the astragalus is rotated laterally beneath the tibio- fibular arch and is brousjht into violent contact with the end of the outer malleolus. This process is 476 Surgical Applied Anatomy. [Chap. xxiii. pushed outwards, and acts as one end of a lever. Tlie fulcrum is secured by the unyielding tibio- fibular ligaments, and the fibula breaks at the other end of the lever, a point some two to three inches above the Fig. 54. — Diagrams to illustrate the Mechanism involved in Fractures of the Lower End of the Fibula. A, Parts in normal position; a, tibio-fibular ligaments; 6, external lateral liga- ment; c, internal lateral ligament; b, fracture of fibula due to e version of foot ; c, fracture of Jibula due to inversion of foot. end of the bone (Fig. 54, b). In forcible inversion of the foot, the astragalus undergoes a little lateral rota- tion in the opposite direction ; the external lateral ligament is greatly stretched, and tends to drag the end of the outer malleolus inwards. If the liga- ment yields, the case will probably end as a sprained ankle, or pass on to a dislocation inwards of the foot. But, if it remains firm, the end of the fibular lever Chap. XXIII.] The Ankle and Foot. 477 (the tip of the malleolus) is drawn towards the middle line, the fulcrum is secured by the tibio- fibular ligaments, and the shaft breaks at the other end of the lever, some few inches above the end of the bone (Fig. 54, c). It will be seen that in the fracture due to eversion the upper end of the lower fragment is displaced towards tlie tibia, while, in the lesion due to inversion, it is displaced from that bone. From a careful examination of all the cases of frac- ture of the lower end of the fibula admitted into the London Hospital during the time I held the post of surgical registrar there, I convinced myself that the lesion is much more frequently due to eversion than to inversion of the foot. I think it may be said that a fracture of the lower end of the fibula due to simple inversion of the foot is not possible unless the ex- ternal lateral ligament remains entire. In the outward luxation, better known ^^ Pott^ s frac- ture, the condition is such as has just been described in connection with the effects of eversion of the foot upon the fibula. That bone is always broken some two or three inches above the malleolus, the deltoid ligament is torn, or the tip of the inner malleolus wrenched off*. The astragalus is so rotated laterally that the foot is much everted, its outer edge is raised, while its inner edge rests upon the ground. The inferior tibio- fibular ligaments remain intact. If they yield, an unusual form of fracture or dislocation is produced, as already stated. Boyer relates a case, considered to be unique, where the foot was luxated outwards, but without any fracture of the fibula. That bone, however, had been forced upwards entire, and its head dislocated from the articular facet of the tibia. A horizontal dislocation outwards, without rotation of the foot and without fracture of the fibula, is possible if the inferior tibio-fibular ligaments are entirely torn. In Dujniytren^s fracture (a rare injury) the fibula 47 8 Surgical Applied Anatomy. [Chap. xxiii. is fractured from one to three inclies above the malleolus, the inferior tibio - fibular ligaments are entirely lacerated, or the portion of the tibia to which they are attached is torn away, and remains connected with the lower fragment of the fibula. The foot is dislocated horizontally outwards, and is drawn upwards, the extent of the upward displace- ment depending upon the height at which the fibula breaks. In the inward luxation the external lateral liga- ment is torn or the tip of the outer malleolus dragged away, the deltoid ligament is intact, but the internal malleolus is commonly broken by the violence with which the astragalus is brought into contact with it. That bone itself may be broken, and is in any case rotated laterally, so that the foot is inverted, and its inner border much raised. In all forms of this dis- location, whether simple or complicated, the inferior tibio-fibular ligament remains intact. 2. The antero-posterior dislocations — Backwards ; forwards. These injuries are brought about by great force applied to the foot while the leg is fixed, or more commonly by sudden arrest of the foot during some violent impulse given to the body, as on jumping from a carriage when in motion. In the luxation backwards the astragalus is displaced behind the tibia, while the articular surface of the latter bone rests upon the scaphoid and cuneiform bones. The anterior and posterior ligaments are entirely torn, and a great part also of the two lateral bands. The fibula is broken some two or three inches above the malleolus, and there is usually a fracture also of the inner malleolus. The luxation forwards is of extreme rarity. In the few reported cases one or both malleoli were broken. K. W. Smith believes that the dislocation is never complete. Chap, xxiii.] The Ankle and Foot. 479 3. The. dislocation upwards. — In tliis rare accident the inferior tibio-fibular ligaments are ruptured, the two bones are widely separated at their lower ends, and the astragalus is driven up between them. The anterior and posterior ligaments are entirely rup- tured, but the lateral ligaments usually escape with but some slight aceration. The accident appears to be generally caused by a fall, the patient alighting flat upon the soles of the feet. Mr. Bryant records a case in which both feet were similarly dislocated upwards. The foot. — There are two arches in the foot, an antero-posterior and a transverse. 1. The antero-posterior arch has its summit at the astragalus and ankle-joint. It may be considered Fig. 55.— Antero-Posterior Section of the Foot (Eiidinger). 1, Tibia; 2, astragalus; 3, oscalcis: 4, pcaplioid ; 5. int. cuneiform; 6, first luetatarsal bone ; 7 and 8, phalanges of great toe. as composed of two piers. The hinder pier contains the posterior parts of the astragalus and os calcis, the anterior pier the remainder of those bones with tlie rest of the tarsus, the metatarsus, and the phalanges (Fig. 55). 480 Surgical Applied Anatomy. [Chap. xxiii. The foot rests upon the heel, the heads of the metatarsal bones, and the outer margin of the foot. The hinder pier is solid, is made up of two strong bones, and contains only one joint. It serves to support the main part of the weight of the body, and gives a firm basis of attachment to the muscles of the calf. The anterior part of the arch, on the other hand, contains many small bones and a number of complicated joints. It serves to give elasticity to the foot, and to diminish the effect of shocks received upon the sole of the foot. The comparative value of the two piers of the arch in this latter respect can be estimated by jumping from a height and alighting first upon the heels and then ujion the balls of the toes. The inner part of the arch is much more curved than the outer, and forms the instep. 2. The transverse arch is most marked across the cuneiform bones. It gives much elasticity to the foot and affords protection to the vessels of the sole. These two arches result from the shai)e of the component bones, and are maintained by the various ligaments. The peroneus longus tendon, and nearly all the ligaments which connect the first and second rows of tarsal bones on both the plantar and dorsal aspects, are inclined forwards and inwards, and by this arrangement are well adapted to maintain the integrity of the transverse as well as of the antero-posterior arch. The cliief joints of the foot. — The articu- lation between the os calcis and astragalus forms a double joint. The posterior joint, that behind the interosseous ligament, has a separate synovial sac, while the anterior communicates with the synovial cavity of the mid-tarsal articulation. The two bones are held together not only by the int(;rosseous, the internal, external, and posterior calcaneo-astragaloid ligaments, but are supported also by the external Chap. XXIII.] The Ankle and Foot. 481 calcanoo-soaplioid lii^ament, the two lateral ligaments of the ankle, and the tendons about the part. The articulation permits of adduction and al)duction, and of some rotation of the foot beneath the astragalus. Adduction is associated with some turning of the toes inwards, and abduction with some turning of them outwards. Dislocations of the astrag^alus. — This bone is sometimes luxated alone, being separated from its connections with the os calcis, the tibia, the fibula, and the scaphoid bone. The displacement may be either forwards, backwards, or laterally. The lateral luxations are nearly always oblique, the bone passing as a rule forwards as well as inwards or outwards. The luxation forwards is by far the most common lesion, and next in frequency being a luxation out- wards and forwaids. The backward displacement is extremely rare. The dislocations are usually com- plete, are very often com2:)Ound, especially when in the lateral direction, and are commonly associated with fracture of the tibia or fibula, or of the astragalus itself. A lateral complete dislocation is impossible Avithout fracture of one or other malleolus. In these injuries the interosseous ligament between the os calcis and astragalus is entirely torn, as are also a greater part of the lateral ligaments of the ankle, and the various bands that connect the astragalus with the OS calcis and scaphoid. In all instances the malleoli are brought nearer to the sole. In the antero-posterior luxations the foot as a rule undergoes no rotation, but in the luxation of the bone forwards and outwards it becomes inverted, and in the displace- ment forwards and inwards everted. Dislocation of the os calcis. — This bone, although often fractured, is very rarely luxated. When displaced, however, it is usually displaced outwards, and is torn away from its attachments to F F 4^2 Surgical Applied Anatomy. [Chap. xxiii. the astragalus and cuboid, or from the former bone alone. Subastrag^aloid dislocations of the foot. — In these lesions, which are not very uncommon, the astragalus remains in position between the tibia and fibula, while the rest of the foot is dislocated below that bone. The luxation, therefore, concerns the calcaneo-astragaloid and astragalo-scaphoid joints. The foot may be displaced either forwards, backwards, or laterally. The forward dislocation is extremely rare, and the lateral luxations are nearly always oblique. In the most usual displacement the foot is dislocated outwards or inwards, and is at the same time carried backwards. These luxations are often compound, especially when lateral. They are, as a rule, incomplete as regards the calcaneo-astragaloid joint, while, on the other hand, the displacement of the astragalus from the scaphoid is in nearly every instance complete. In all cases the interosseous liga- ment between the os calcis and astragalus must be torn, and there will also be more or less laceration of the astragalo-scaphoid ligament, and of one or both of the lateral bands of the ankle joint. The malleoli are very often fractured. It is only necessary to notice in any detail the two lateral luxations, as being the only common forms. In the inward dislocation the foot is inverted, its inner border is raised, is shortened, and rendered concave, while its outer border is lengthened and made convex. The deformity much resembles that of talipes varus. The head of the astragalus with the outer malleolus form a projection at the outer aspect of the foot, while below them a deep hollow exists. The inner border of the os calcis is very prominent at the internal side of the limb, while the inner malleolus is buried in the hollow left by the displacement of that bone. The calcaneum and scaphoid are approximated. Chap. XXIII.] The Ankle and Foot. 483 In the outward luxation the foot is abducted, its outer border is raised, and the deformity produced is not unlike that of talipes valgus. The outer malleolus is lost in the hollow caused by the eversion of the foot, while the tibial malleolus and head of the astragalus form a projection on the inner aspect of the limb. The medio-tarsal Joint is composed of two articulations, the astragalo - scaphoid and calcaneo- cuboid. The ligaments supporting the former joint are the external and inferior calcaneo-scaphoid and the astragalo-scaphoid ; while the latter articulation is maintained by the internal and dorsal calcaneo- cuboid ligaments, and the long and short plantar. Movement is somewhat freer in the astragaloid than in the calcaneal segment of the joint. The move- ments permitted in the articulation as a whole consist of flexion and extension, with some rotation around an antero-posterior axis whereby the sole can be turned in or out. Flexion is associated with inward rotation of the sole and adduction of the toes, extension with outward rotation of the sole and abduction of the toes. It should be noted that the movements of turning the toes either in or out take place mainly at the hip-joint ; while the turning of one edge of the foot either up or down is a movement that mostly concerns the medio-tarsal and calcaneo-astrasraloid joints. The chief deformities in club-foot take place about the former articulation. Club-foot. — It is usual to divide the various forms of talipes, or club-foot, into four main divisions, viz., (1) T. equinus ; (2) T. calcaneus; (3) T. varus; and (4) T. valgus. Four secondary forms result from combinations of these principal varieties, viz., T. equino-varus, T. equino-valgus, T. calcaneo-varus, and T. calcaneo-valgus. 1. Talipes equinus. In this deformity the heel is 484 Surgical Applied Anatomy. [Chap, xxiii. drawn up, and the patient walks upon tlie balls of the toes. The contracting muscles are those of the calf attached to the tendo Achillis. In a well-marked case the os calcis is much raised, and may even be brought in contact with the tibia. The astragalus is displaced downwards, and projects upon the dorsum. The foot tends to become more and more bent at the medio-tarsal joint, until at last the scaphoid may even touch the OS calcis. The ligaments of the sole are usually much contracted. 2. Talipes calcaneus. In this form of club-foot the toes are drawn up, and the patient walks upon the heel. The contracting muscles are the extensors on the anterior aspect of the limb. The os calcis is rendered more vertical, and the astragalus becomes so obliquely placed that part of its upper articular surface may project beyond the tibia in a backward direction. 3. Talipes varus. This is the commonest form. In a well - marked congenital case there is a four- fold deformity : (1) The heel is drawn up by the muscles attached to the tendo Achillis ; (2) the foot is adducted ; and (3) its inner edge is drawn up- wards by the contraction of the tibialis anticus and posticus ; (4) the sole is contracted by the flexor longus digitorum muscle and the shrinking of the plantar fascia and ligaments. In this variety of talipes the os calcis is drawn into a more vertical position. The astragalus is displaced forwards and downwards, so that some part of its upper articular surface becomes superficial on the dorsum. The scaphoid is displaced upwards and backwards, until its inner border often touches the internal malleolus. The three cuneiform bones follow the scaphoid, and the cuboid becomes the lowest bone in the tarsus. 4. In talipes valgus the foot is abducted and its ou ter border drawn upwards. The contracting muscles Chap. XXIII.] The Ankle and Foot. 485 are the two peronei. In a well-marked congenital case the os calcis is found a little raised and the astragalus is displaced forwards and downwards. The scaphoid is so rotated that its inner part is depressed and its outer raised. The internal portion of the bone forms one of the two projections obvious on the inner side of the foot, the other prominence being formed by the head of the astragalus. The cuboid is found to be a little rotated outwards. The arch of the foot is lost, and all those ligaments are stretched that serve to support and maintain that arch. Of the mixed, or secondary, forms of talipes nothing need be said. They are the results merely of a combination of the primary varieties. As trouble is often caused in talipes by pressure being brought to bear upon an unusual part of the foot, it is well to note upon what portion of the member the patient treads in the different varieties of the deformity. In varus the " tread " is mainly upon the outer side of the fifth metatarsal bone ; in valgus upon the internal malleolus and scaphoid ; in equinus upon the bases of all the toes ; in equino-varus upon the base of the little toe ; in equino-Aalgus upon the base of the great toe ; in all forms of calcaneus upon the heel. Flat-foot, or splay-foot^ are the names given to a deformity due probably to the yielding of certain ligaments, whereby the arch of the foot is lost and the sole becomes more or less perfectly flat. The foot, at the same time, is abducted, and the outer border is often a little raised, so that the patient walks mainly upon the inner side of the foot. This deformity is met with in those who stand a great deal, and is the direct result of yielding of the tarsal ligaments from long-continued pressure. When the weight of the body is brought to bear on the foot placed flat upon the ground, it will be transmitted in 486 Surgical Applied Anatomy. [Chap. xxiii. an oblique direction from above downwards and in- wards. The foot therefore tends to become abducted, a tendency resisted by such powerful ligaments as the internal lateral of the ankle and those connecting the OS calcis Avith the astragalus. In flat-foot these liga- ments yield, and the toes consequently are turned out or abducted. The ligament, however, that is mainly affected in this deformity is the inferior calcaneo- scaphoid. This strong band of fibres supports the head of the astragalus and holds up the very key- stone of the plantar arch. When it yields, the head of the astragalus is pressed forwards, downwards, and inwards by the superincumbent weight, and the foot beyond becomes, as a consequence, over-extended and rotated out. The long and short plantar liga- ments also, which contribute so much to the main- tenance of the arch of the foot, in time yield, and allow of a still greater degree of deformity. In neglected cases the distortion is rendered more or less permanent by alterations in the shape of the tarsal bones, and by a contraction of such ligaments as have been relaxed by the deformity. The foot being abducted, and its outer border a little raised, the peronei muscles become relaxed, subsequently shorten and contract, and so contribute to the permanency of the disorder. It will be understood that the abnormal pressure brought to bear upon the various tarsal bones and articulations will cause severe pain to be often associated with this affection. It may be noted that the medio-tarsal joint, which is so consjDicuously involved in the distortion, is supplied by the anterior tibial, musculo-cutaneous, and external plantar nerves. According to Duchenne (of Boulogne), flat-foot is rather a muscular affection in the first instance, and is due to a weakening of the peroneus longus, the sinking of the plantar arch being subsequent thereto. Chap. xxiiL] The Ankle and Foot. 487 The tarsal bones, owing to their spongy character, are readily broken by direct violence, as in severe crushes. The soft parts that cover these bones being scanty upon the dor- sal aspect of the foot, it follows, that these accidents are often compound and associated with much lacer- ation of the integuments. The tarsal bone the most frequently fractured is the OS calcis. This bone ^--'iaS^ofc^«!4^'!i^^- may be broken by a fall 6..-Ji^|^|i^;J^^ upon the heel, and in many m^'^'^^^^cK.-.iti.A.l instances has been the only one fractured by such an accident. A few cases have been recorded of fracture of the calcaneum by mus- cular violence, the muscles producing the lesion being those attached to the tendo Achillis. Thus, Sir A. Cooper reports the case of a woman, aged forty-two, in whom a large fragment of the posterior part of the OS calcis was torn away by the muscles and drawn some two and a half inches away from the heel. The accident was caused by her taking a false step. Abel has collected three cases of fracture of the sustenta- culum tali. He believes that this injury may be Fig. 56. — Oblique Antero-Posterior Section of the Foot (Rudiuger). 1, Tibia ; 2, fibula; X nstngnius ; 4, os calcis; 5, external lateral ligament; 6, iiuern-il lateral ligmueiit : 7, inter- osseiiuslitrameHt between astragalus and f)P calcis ; 8, head of astragalus ; 9, scaphoid; 10, ll, and 12, the three cuneiform bones ; 13, cuboid. 488 Surgical Applied Anatomy. [Chap, xxiii. produced by falls upon the sole or by extreme supi- nation (rotation outwards) of the foot, whereby the astragalus is forced violently against the process. The astragalus alone may be broken by a fall upon the feet, and such accidents are often associated with fractures of both that bone and the os calcis. It must be noted, however, that in a fall, when the patient alights upon the feet, the tibia and jQbula are much more likely to be broken than are the tarsal bones, since the bones of the leg transmit the weight of the body directly, whereas that weight is much diffused and broken-up when passing through the foot with its many bones and joints. The metatarsal bones and phalanges are nearly always broken by direct violence. I had, however, under my care at the London Hospital a man who had broken the shafts of the three outer metatarsal bones by simply slipping off the edge of the curb. With regard to the luxations of the foot not yet considered, it may be said that the cuboid is never dislocated only. Walker reports a case of dislocation of the scaphoid alone, that structure being quite separated from the astragalus and cuneiform bones. The acci- dent was brought about by alighting upon the ball of the foot when jumping, and the little bone was found projecting on the dorsum. Mr. Bryant has mentioned an instance of dislocation of the scaphoid inwards. As a rule, however, this bone when displaced is dislocated along with the astragalus. Of the cuneiform bones the one most often lux- ated alone is the internal. The attachment of the tendons of the tibialis anticus and peroneus longus about the internal cuneiform and first metatarsal bones renders it common for the latter to follow its tarsal colleaijue when dislocated. Mr. Luke has recorded a case of incomplete luxation of all three cuneiform bones upwards, and at least Chap. XXIII.] The Ankle and Foot. 489 three cases have been described of dislocation of the internal bone upwards and backwards, together with a like displacement of all the metatarsals. One or more of the .metatarsal bones may be luxated, or the entire series may be displaced upwards, downwards, inwards, or outwards, the first-named lesion being the most common. In rarer instances, one bone has been thrown in one direction and its fellow or fello"ws in another. Dislocation of the first phalanx of the great toe is often very difHcult to reduce, as is also the case in the corresponding luxation in the thumb. When the displacement is dorsal, the difficulty is probably due to the sesamoid bones, which in this joint take the place of the glenoid ligament or fibro-cartilaginous plate of the other toes. " Like the glenoid ligaments, the sesamoid bones are much more firmly connected with the phalanx than with the metatarsal bone, and thus get torn away and shut back behind the head of the metatarsal bone ; or it may be that the sesamoid bones, retaining their connections with the lateral ligaments of the joint as well as with the short flexor tendons, are separated from one another, and so allow the head of the metatarsal bone to pass forwards, and thus become nipped, as it were, in a button-hole between them " (Henry Morris). There are six synovial cavities in the foot, excluding that of the ankle-joint, viz., one for the posterior calcaneo-astragaloid joint, a second for the anterior calcaneo-astragaloid and astragalo-scaphoid joints, a third between the os calcis and cuboid, a fourth between the latter bone and the two outer metatarsals, a fifth for the joint between the inner cuneiform and first metatarsal bones, and a sixth for the remaining articulations (Fig. b^\ These synovial cavities tend greatly to diffuse disease among the various bones of the foot when once one bone has 490 Surgical Applied Anatomy. [Chap. xxiii. become inflamed. The best position, therefore, for bone disease, with reference to the question of exten- sion, would be in the hinder parts of either the OS calcis or astragalus, and one of the worst positions would be as- sumed by disease in- volving the scaphoid bone. The tarsal bones, from their cancellous structure and exposure to external influences and injuries, are pecu- liarly liable to become the seat of caries or necrosis. Syme's ampit- tEition at the ankle. In the heel-flap are cut the integuments, the external saphenous nerve and vein, the peroneus longus, pero- neus brevis, tibialis posticus, flexor longus digitorum, flexor lonaus pollicis, tendo Achillis, and posterior tibial vessels and nerves. In the dorsal flap are cut ciis;i,fle.xorl()ngus(iit'itorum; J, peroneus xi ^ nT,+zirmTYi/:.n+c. -fiKi brevis; k, peroneus l()nf,'us ; I, tendo tno nitegUmCntS, tlDl- Acliillis; w, soiuemusclesofthfi sole that y Q-nfir^nc f^vfoncriT' are not usually left in tbis operation; n, dllfc) diiticLlb, tJA-teiibUi anterior tibial vessels; o, posterior tibial ^^,^,^„^- , J-:^;.*-^^,,,^ vessels ; p, posterior tibial nerve. COmmuniS Cllgltorum, extensor proprius pol- licis, peroneus tertius, anterior tibial vessels and nerve, musculo-cutaneous nerve, and internal saphenous Fig. 57. — Syme's Amputation (Agatz). a. Tibia; &, fibula; c, tibialis anticus ; d, extensor projirius pollicis ; e, extensor communis digltorum ; f, peroneus tertius ; g, flexor longus pollicis; /(, tibialis posti Chap. XXIII.] The Ankle and Foot. 491 nerve and vein. The position of the principal struc- tures divided is shown in Fig. 57. It is not usual to dissect up any of the muscular tissue of the sole as shown in Agatz's plate. It should be noted that the integuments of the heel derive their blood-supply, which is very free, mainly from the external calcaneal branch of the posterior peroneal artery, and the internal calcaneal from the external plantar. The supply of the part is also aided by branches from the tarsal artery, by the internal malleolar branch of the posterior tibial, and the outer and inner malleolar vessels from the anterior tibial trunk. The nerves supplying the integuments of the heel are the calcaneal Branch of the external saphenous and the calcaneal and plantar cutaneous twigs from the posterior tibial. In PirogfoflPs amputation, the parts divided in the anterior flap are the same as in Syme's opera- tion. In the heel or sole flap the same structures also are cut as in the corresponding flap in a Syme, with the exception that the tendo Achillis is not divided, the flexor brevis digitorum, abductor pollicis, abductor minimi digiti, and flexor accessorius are cut, and the plantar vessels and nerves are divided in the place of the posterior tibial. Cliopart^s operation, an amputation at the medio-tarsal joint. In the dorsal flap are cut the integuments, the extensor communis and brevis digi- torum, extensor proprius pollicis, tibialis anticus, peroneus tertius and brevis, the musculo cutaneous, anterior tibial, and two saphenous nerves, the dorsal artery, and the dorsal plexus of veins. In the plantar flap are found divided the integuments, plantar fascia, flexor brevis digitorum, abductors of the great and little toes, flexor accessorius, and tibialis posticus tendon. If the flap be well dissected up from the 492 Surgical Applied Ana tomy. [Chap. xxiil bones, parts of the short flexors of the great and little toes, the adductor pollicis, and transversus pedis will be found cut in the flap. The tendons of the long flexors of the digits and great toes, the peroneus longus, and the plantar vessels and nerves are also divided (Fig. 58). liis franc's operation, or am- putation through the tarso-metatarsal line of joints. In the dorsal flap the same structures are divided as are cut in the correspond- ing flap in Cho- part's amputation. In the plantar flap also the parts divi- ded are the same as in that procedure, with the exception that the flexor ac- cessorius and the tendon of the tibialis posticus es- cape section. In opening the line of joints it should be noted that the articulations between the three outer metatarsals and the corresponding tarsal bones form a line sufficiently straight to be traversed by the knife in one cut when once the blade has been introduced. The joint also between the first metatarsal and internal cuneiform bones is in a straight line and readily opened. The most difficult part of the dis- articulation concerns the separation of the second Fig. 58. — Chopart's Operation (Agatz). a, Astragalus ; b. ns calcis ; c, extensor proprius pollicis: d, tibialis anticus; e, extensor com- munis digitorum ; /, peroneus longus ; g, abduc- tor minimi digiti ; ft., flexor brevis digitorum ; i, flexor longus digitorum ; i, abductor pollicis ; h, flexor longus pollicis; I, dorsalis pedis artery ; TO, internal plantar artery; n, external plantar artery. Chap, xxiii.] Nerves of Lower LnfB. 493 metatarsal bone, which is deeply lodged between the tarsal secrments. The chief bond of union between this bone and the tarsus is effected by a strong interosseous ligament tliat passes between it and the internal cuneiform. In Fig. 59 tlie knife is placed in the position required to divide that liga- ment. Fiof. 60 shows the position of the more important structures that are divided in amputation of the sreat toe tosjether with its metatarsal bone. The nerve sup- ply of the loAver limb. — In Fig. 61 is shown the cutaneous nerve - supply of the inferior extremities on both the anterior and the posterior aspect. Fig- 59.— Lisfranc's Operation (Agatz). "P.-ivq1tcoc r>-P flio IrkTiTOY' «. *> c. Inner, middle, and outer cuneiform j:clld.i_)bfb ui \AW luwt^i bones ;d, cuboid ; e,/, thenietatarsalbon.es; limbs are common, but are more often due to some lesion in the inferior segment of the cord than to damage received by any one indi^ddual nerve. Cases, however, are recorded where a single trunk has been injured and a limited form of paralysis has followed in consequence. Paralysis of the anterior criu'al nerve has been caused by injuries to the lower part of the vertebral column implicating the cauda equina, by g, tibialis anticus ; h, extensor proprius pollicis ; i, extensor craraunis dipltorum ; j, extensor brevis digitorum ; fc, extensor tendons ; /, dorsalis pedis artery. 494 Surgical Applied Anatomy. [Chap. xxiii. fractures of the pelvis, by tumours of the pelvis, by psoas abscess, by fractures and dislocations of the femur, and by stabs in the region of the groin. In this nerve lesion the patient is unable to flex the hip and to raise the body from the recumbent position (ilio-psoas). The power of extending the leg at tlie knee is lost (q[uadriceps extensor cruris") ; the function Fig. 60. — Amputation of Great Toe, with its Metatarsal Bone i^Agatz). a. Internal cuneiform bone ; b, adductor pollicis; c, extensor longus poUicis; d, flexor longus pollicis ; e, plantar branch of dorsalis pedis artery. of the sartorius is destroyed and that of the pectineus impaired. Sensation is impaired in parts supplied by the internal and middle cutaneous nerves and the long saohenous nerve. Paralysis of the obturator nerve alone is a rare condition, although it may be found associated with a like lesion of the preceding trunk. It may be brought about by the pressure exercised upon the nerve in cases of obturator hernia and by the fcEtal head during delivery. The muscles implicated are the adductors, the gracilis, pectineus, and external ob- turator. The patient is unable to press the knees together, or to cross the legs. Rotation outwards of the thigh is difficult, and sensation is affected in the 5 \ \ 3/ 8 G\ i 10 Fig. 61.— Cutaneoits Nerve-Supply of Lower Limb. Avterior Aspect.— \ , Ilio-iiicruinal ; 2, genito-cniral ; .3, extornni cutnneouB ; 4. middle cutaneous ; 5, internal cutaneous; 6, patellar plexus ; 7, branches of external popliteal; 8, internal eaphenous ; 9, musculo- cutaneous; 10, external saphe- nous ; 11, anterior tibial. . . , Posterior Aspect.— \, 2, and S, sraall sciatic; 4, external cutaneous; 5, internal cutaneous; 6, internal saphenous ; 7, branches of external popliteal ; 8, short saphenous ; 9, posterior tibial ; 10, internal saphenous ; 11, internal plantsir ; 12, external plantar. 496 Surgical Applied Anatomy [Chap, xxiii. portions of the skin supplied by cutaneous branches of the nerve. Paralysis of the internal popliteal nerve, — In this condition there is inability to extend the ankle and to flex the toes (flexor longus digitorum, flexor proprius pollicis, tibialis posticus, gastrocnemius, and soleus). The patient is unable to stand upon the toes owinoj to loss of function in the two last-named muscles. The power of adducting the foot and of raising its inner border is impaired (tibialis posticus), and lateral movements in the various toes are lost owing to the paralysis of all the small muscles of the sole. Sensation is impaired over the plantar aspect of the toes, the sole of the foot, and in part of the lower half of the back of the leg. In paralysis of tlie external popliteal nerve the action of the muscles on the front of the leg is lost. The foot hangs do\vn and the toes catch the ground in walking. The foot can be neither flexed nor abducted (extensor communis digitorum, extensor propius pollicis, peroneal muscles). Adduction is im- perfectly performed, owing to paralysis of the tibialis anticus. Extension of the toes is only possible to the slight extent effected by the interossei muscles. The arch of the foot becomes flattened owing to loss of the support furnished by the peroneus longus. Sen- sation is impaired over the front and outer side of the leg and on the dorsum of the foot, and also over some part of the back of the leg, owing to paralysis of the communicans peronei. When the great sciatic nerve is paralysed there will be, in addition to the effects produced by loss of function in the two preceding nerves, an in- ability to flex the knee, owing to paralysis of the hamstrings, while rotation of the limb may be impaired by loss of power in the quadratus femoris and obturator internus muscles. 497 part Vh CHAPTER XXIV. THE SPINE, The vertebral column combines in a remarkable way many very different and complicated functions. It acts as the central pillar of the body, and as the column that supports the weight of the head. It connects the upper and lower segments of the trunk. It gives attachments to the ribs. It has the property of mitigating the effects of shocks that are transmitted from various parts of the body. It permits, to a wonderful degree, of a number of most complicated movements ; and, lastly, forms a solid tube for the reception of the spinal cord. It owes much of its elasticity, and of its power of breaking up divers forces communicated to it, to its curves, which are most fully developed in adult life. At the time of birth these curvatures do not exist, and the infant's spine is straight. As the child begins to sit and stand and walk, and throw, indeed, increas- ing responsibility upon the column in the matter of supporting weight, the curves begin to form. The only marked curve seen in the back of the young child is a general curving of the column backwards — a cyphosis. When the infant is first encouraged to sit erect, this is the outline assumed by the spine, and in some weakly children, and especially in those afflicted with rickets, this curvature is often very pronounced. GG 49^ Surgical Applied Anatomy. [Chap. xxiv. The normal curvatures of the column are maintained to a great extent b j the intervertebral discs. These substances are twenty-three in number, and make up nearly one-fourth of the entire length of the spine. If the discs be removed, and the vertebrae be articulated in the dry state, the cervical and lumbar convexities almost disappear, and the column tends to present one great curvature, the concavity of which is forwards, and the most marked part of which corresponds to a point just below the middle of the dorsal region. This somewhat resembles the curve seen in the spines of the aged, and in such individuals it may be to no small extent due to the shrinking of the intervertebral discs. It is by means of the discs that the movements of the spine are in the main permitted, and it will be found that they are most developed in regions where most movement is allowed. They act also as springs in giving elasticity to the column, and in economising muscular action, while at the same time they play the part of buffers in modifying the effect of shocks trans- mitted along the spine. Although the motion permitted between any two individual vertebrae is not extensive, yet the degree of movement capable of being exercised in the column as a whole is considerable. This movement is least free at the dorsal region, and is most extensive in the neck and loins. In the lumbar region (the base of the column) exists the greatest degree of motion per- mitted in the spine, and here is allowed, not only forward and backward flexion, but also lateral bending, and a certain amount of rotation. In the cervical region flexion in the antero-posterior direction is not so ready as it is in the loins, although the neck enjoys the greatest degree of rotation and of lateral flexion. Spraiii)^ of tlie vertebral column. — The many joints and ligaments of the part, and the varied and Chap. XXIV.] The Spine. 499 violent movements to which it may be exposed, render it veiy liable to be the seat of sprains. These injuries, however, cannot reach any great magnitude, for so closely are the individual vertebrae articulated, that any force severe enough to produce other than slight tearing of the ligaments will tend to cause a fracture or dislocation of the bones. Sprains are most commonly met with in the cervical and lumbar segments of the spine. This localisation is due to the mobility of those parts, and to their tendency to diffuse any violence transmitted to them, and so to render it more general. For it is to be noted that the more localised an injury, the more likely it is to produce a fracture or dislocation rather than a sprain. In the cervical region, also, the tendency to sprain is increased by the near articulation of the column with the head, and the possibility of any violence applied to the skull being transmitted to the spine. Sprains of the spine are not apt to be associated with the external evidences of ecchymosis, since be- tween the skin and the column there intervene not only many layers of muscles, but also dense expan- sions of fascia. It has already been pointed out that sprains in the loin, produced by severe bending forwards of the column, may be associated with some damage to the kidney, and consequent hsematuria (page 328). A sprained back is often the seat of a considerable degree of pain and stiffness, that persists long after the immediate effects of the lesion must have passed away. Such a condition may be understood by noticing that the column presents a vast number of separate articulations, each provided with cartilage, synovial membrane, and capsular ligaments. These joints have no qualities that exempt them from the common evils incident to sprains of more superficial articulations ; 500 Surgical Applied Anatomy, [Chap. xxiv. and there is little doubt that tlie long-felt pain and inconvenience often depend upon some synovitis of the vertebral joints. In a few cases this synovitis has gone on to suppuration, and in one instance at least the pus so formed found its way into the spinal canal, and induced some mischief in the cord. Fractures and dislocations of tlie spine. — The effects of violence applied to the column are much diminished by the general elasticity of the spine, by its curves, and by the circumstance that it is composed of a number of separate segments. Each vertebra meets the one immediately above or below it at three points of contact, the body and the two articulating processes. The bodies are separated by the inter- vertebral disc, which acts as an excellent spring or buffer in modifying the eff'ects of violence. The ar- ticulating processes are more or less wedge-shaped, the thin edge of one being applied to the base of the other. When a force is applied to the column that tends to compress the vertebrae together, the bases of the two wedges are brought in more and more close relation, and thus an increasing resistance is offered to the com- pressing power. The parts of the spine most liable to injury are (1) the atlo-axial ; (2) the cervico-dorsal ; and (3) the dorso-lumbar. In the atlo-axial region the parts not only enjoy a very considerable degree of movement, but are very directly influenced by many forms of violence applied to the head. In the two other regions it will be noted that a flexible part of the spine joins a comparatively rigid segment of it, and thus violence applied to the column in either of these districts is apt to be concentrated rather than diflfused. The mechanism is in a way illustrated by the circumstance that a fishing-rod when it snaps commonly breaks near a joint, that is to say, at a spot where a flexible seg- ment of the rod meets a less elastic portion. In the Chap. XXIV.] The Spine. 501 dorso-lumbar region, moreover, the vertebrae, although they have to support almost as much weight as have those of the lumbar region proper, are yet dispro}}or- tionately small in size. Being placed, also, near the middle of the column, they can be influenced on all sides by a powerful amount of leverage. The gravity of all injuries to the spine depends upon the risk of damage to the cord enclosed in the column. Apart from this complication, fractures and disloca- tions in this region are apt to do well, and if the patient survive, the former lesions nearly always heal readily. The position of the cord within the vertebral canal and the arrangement of its membranes are such that it presents many facilities for escaping injury from violence. These will be dealt with subsequently in speaking of the cord itself. It may, however, be noted here that the construction of the vertebrse, and their relation to one another, are of a character to afford much protection to the cord, even in cases where they themselves are extensively damaged. *' Being lodged in the centre of the column, it (the cord) occupies neutral ground to forces which might cause fracture. For it is a law in mechanics that when a beam, as of timber, is exposed to breakage, and the force does not exceed the limits of the strength of the material, one division resists compression, another laceration of the particles, while the third, between the two, is in a negative condition." (Jacobson, Holmes' "System '"). Now, it happens that fractures of the spine are most often due to violence that bends the column forwards. The anterior segment, in such a case, will be subject to compression, the posterior to laceration, and the intermediate portion will be in a neutral con- dition. \Yhen the spine is examined, it will be found that its anterior part, composed of the large cancellous bodies, is excellently adapted to resist the effects of 502 Surgical Applied Anatomy. [Chap. xxiv. compression^ while its posterior parts, composed of slighter and more compact bones and surrounded by many strong ligaments, are well arranged to resist the effects of a tearing force. The spinal cord, situated between these two divisions, occuj)ies the position of least danger. The vertebrae may be fractured without being dis- located, but a dislocation without a fracture is rarely possible. It would appear, indeed, that a luxation of the spine, with no fracture of bone, cannot occur in either the dorsal or lumbar regions. Mr. Jacobson, in the essay above referred to, writes, "I believe I am correct in stating that there is no case recorded, and thoroughly verified, in recent years, of dislocation of the lumbar or dorsal verteVjrse, unaccompanied with any fracture of the body, transverse or articular processes," Dislo- cation without fracture has been met with in the cervical spine, although even there, if we except the first two vertebrae, it is very rare. When it occurs it most often involves the fifth vertebra, which, with the rest of the column above it, is displaced for- wards and downwards. Luxations in other directions have been noted, but they are extremely uncommon. The possibility of luxation in the cervical region with- out dislocation is explained by the small size of the vertebral bodies, the obliquity of their articular pro- cesses, and the relatively slight opposition they offer to displacement when compared with like processes- in the other parts of the column. The luxation is usually bilateral and incomplete, and the result of a forcible bending of the head and upper part of the spine for- wards and downwards. When situated high up the displacement may be appreciated by an examination of the part through the pharynx, In the complete bilateral dislocation the cord is usually hopelessly crushed. These luxations have been reduced by forcible Chap. XXIV.] The Spine. 503 extension, altliougli the circumstances under'^ which such a procedure is advisable are neither frequent nor very distinctly marked. Since, in severe injuries, dislocation and fracture are so usually associated, it is common to deal with tliese lesions under the title of ''^fracture-dislocation.^^ Fracture-dislocation may be due to (1) indirect, or (2) direct violence. 1. The injuries from indirect violence are by far the more common. They are due to a violent bending of the head, or of the spine above the seat of lesion, forwards and downwards. Thus, the cervical spine has been more than once broken by a "header" into shallow water; while the dorsal vertebrae have been fractured and displaced by the acute bending of the column, produced by a heavy sack falling upon the back of the neck. This form of injury is most commonly met with in the cervical and upper dorsal regions. These parts of the column possess great mobility, the bodies that compose them are not large, and are influenced by violence applied to the head. In a well-marked case there is some crushing of the vertebrae involved, and the usual deformity depends upon a sliding of the centrum above downwards and forwards upon the centrum below. Complete displacement of any two vertebrae from one another is prevented by a locking of the posterior processes. In some cases the luxation is complete, a condition that is least frequently met with in the lumbar spine. In the cervical and dorsal regions, the parts, after the dislocation, may often be returned to their normal position ; but in the loins this replacement is usually impossible, owing to the locking of the large and powerful articular processes. In the neck the laminae and spines may be fractured, while the articulating processes, being broad and nearly horizontal, usually escape, even when there is much displacement of the 504 Surgical Applied Anatomy. [Chap. xxiv. parts. In the dorsal spine the laminae and articular processes are always torn when displacement occurs. In the lumbar region the articular processes usually escape fracture, although they are violently torn asunder. In all cases there is more or less laceration of the intervertebral discs, the supraspinous, inter- spinous, and capsular ligaments are torn, as are also the ligamenta subflava. When the bodies are much crushed and displaced the anterior and posterior common ligaments are commonly ruptured. 2. In the fracture - dislocations due to direct violence the lesion may be at any part of the spine. Some form of direct violence is applied to the back, and the column tends to become bent backwards at the spot struck. In the previous class of injuries it will be noted that the anterior segments of the ver- tebrae suffer compression, while the posterior suffer from the effects of laceration and a tearing asunder of their parts. In lesions due to direct violence the circumstances of the injury are reversed, the posterior segments tend to be crushed together, while the bodies on the front of the spine are separated. Much displacement is very rarely met with in this form of accident. To produce separation of the ver- tebrae the violence must be very extreme, and as a rule the force expends itself upon a crushing of the hinder portions of the spinal segments. It follows from this, also, that injury to the cord is less common and less severe in lesions due to direct violence than in those due to indirect violence. In the atlo-axial region the atlas and occipital bone have been dislocated from one another by direct violence, although the most frequent lesion is a dislocation of the former forwards upon the axis, a lesion usually, if not always, associated with fracture of the odontoid process. The spinous processes may be broken off as a re- sult of well-localised blows. The prominent spines in Chap. XXIV.] The Spine. 505 the lower cervical region and the long processes of the dorsal tract of the column are those that usually suffer. The lumbar spines are less frequently broken, being comparatively small and well protected by the great muscles of the back. The transverse processes and laminae can scarcely be fractured alone. In several instances of fracture-dislocation and of fracture alone the spine has been treyliined, or rather portions of the laminae and spinous processes have been resected. At the present time the operation is con- sidered by most surgeons to be quite unjustifiable. It involves a very deep wound, and an extensive dis- turbance of the muscles and fasci£e of the back. It opens up the spinal canal, and affords an oppor- tunity for blood or pus to enter it. In many cases the rigidity of the injured spine depends upon the locking of the posterior j)rocesses, and in this operation the resection of some parts of those processes would destroy the very desirable fixation of the column. In the majority of instances the cord is crushed by the projection backwards into the canal of the vertebra immediately below the seat of the displacement, a displacement that could not be remedied by any such operation as the present. It is absurd, from an anatomical point of view, to deduce any arguments in favour of trephining the spine from the success of the operation of the same name as applied to the skull. Except in name the two procedures have little in common. The spinal cord is in the adult about eighteen inches in length, and extends from the lower margin of the foramen magnum to the lower edge of the body of the first lumbar vertebra. In some cases it ends at the second lumbar, and in other instances at the last dorsal vertebra. It is to be noted also that in flexion of the spine the cord is a little raised. In the earlier 5o6 Surgical Applied Anatomy. [Chap. xxiv. months of foetal life the medulla spinalis occupies the whole length of the vertebral canal, but after the third month the canal and lumbar and sacral nerves grow so much faster than does the cord itself, that by the time of birth it reaches no farther than the third lumbar vertebra. It is obviously a great advantage, in cases of injury, that the spinal medulla does not occupy that part of the vertebral pillar which joins the base of the column, and which permits not only of considerable movement, but is liable also to frequent wrenches and strains. It is important to recollect that although the cord itself ends at the spot indicated, the dura mater, the arachnoid, and the collection of cerebro-spinal fluid extend as far as the second piece of the sacrum. Injuries inflicted, therefore, upon the sj)ine as low down as this latter ]3oint, may cause death by inducing inflammation of the meninges. The cord in the dorsal region measures about 10 mm. from side to side, and 8 mm. in the antero-posterior direction. The cervical enlargement is largest opposite the fifth or sixth cervical vertebrae, where it measures about 13 mm. from side to side. The greatest part of the lumbar enlargement is opposite the twelfth dorsal vertebra, where its lateral measurement is about 12 mm. The spinal dura mater is a strong and substantial membrane, and between it and the walls of the ver- tebral canal a considerable space exists occupied by loose areolar tissue and a plexus of veins. It will be readily understood that injury and inflammation of the meninges, as results of lesions applied to the spine, are much less frequent than are like complications after injuries to the skull. The looseness of the spinal dura mater, its freedom from any but slight and occasional attachments to the bone, and the space around it in which effusions can extend with little possibility of becoming limited, will explain the rarity Chap. XXIV.] The Spine. 507 in the spine of those complications which follow upon depressed bone, and extravasations of pus and blood in connection with the dura mater within tlie skull. The plexus of thin- walled veins that occupies the interval between the theca and the bones may ])rovo a source of extensive haemorrhage in cases of injury to the column. The blood so poured out tends to gravitate to the lowest part of the canal, and when safficient in quantity may produce pressure effects upon the me- dulhx spinalis. Over the arches at the posterior aspect of the ver- tebrae is situate a plexus of vessels (the dorsal spinal veins) that receives blood from the muscles and inte- guments of the back. These vessels communicate through the ligamenta subflava with the venous plexuses within the spinal canal, and by means of this communication inflammation from without may be conducted to the theca of the cord. Thus spinal meningitis has followed upon deep bed-sores, and upon suppurative affections situated in the immediate vicinity of the spinal laminae. Within the dura mater are two spaces, the sub- dural and the subarachnoid, as in the skull. They are occupied by a considerable quantity of cerebro- spinal fluid, continuous with the collection within the cranium. By means of this open communication inflam- matory affections may readily spread from the cord to the brain. Into these spaces blood may be extrava- sated in cases of injury. Instances have been recorded where the theca has been opened by a wound, and the cerebro-spinal fluid has escaped in large quantities. The position of the cord is such that it is not readily reached in incised and punctured wounds. The only spots at which it is easy of access are the intervals between the atlas and occiput and the atlas and axis. Many cases have been recorded of fatal wound of the cord in these positions. Lower down in the column 5o8 Surgical Applied Anatomy. [Chap. xxiv. the medulla spinalis may be reached if the wound have a certain direction. Thus, a case is reported where a y)ointed body entered the canal between the ninth and tenth dorsal vertebrae, having been introduced from below upwards. Several examples of damage to the cord by sword or bayonet wounds have been put on record, but in most of these instances the wound was associated with some fracture of the protecting bone. Concussion of tlie cord. — After certain in- juries to the back a train of symptoms, usually of a severe and complicated character, have been described, which have been assigned to a concussion or shaking of the spinal cord. In these injuries it is assumed that, as a result of a sudden shock transmitted to it, the cord undergoes certain molecular changes, which lead to a more or less severe disturbance of its function. The condition has been compared to concussion of the brain, al- though it must be owned that the symptoms often accredited to concussion of the cord have a character more complex than that seen in like lesions of the more complex organ, A great many surgeons are inclined to dispute the existence of this lesion, or rather decline to recognise the connection between a certain train of symptoms and a simple molecular disturbance of the cord. It is very probable that in many of the reputed instances of cord-concussion the symptoms (if we except such as are assumed and such as depend upon changes in the brain) are due to a more distinct damage to the medulla spinalis, to haemorrhages, to pressure, and to other gross changes. Without entering into any discussion upon the subject, it may be sufficient to point out some of the anatomical objections that appear to oppose themselves to the common conception of concussion of the cord. The spinal cord is swung or suspended in Chap. XXIV.) The Spine. 509 its bony canal, and is separated from the walls of that canal on all sides by a considerable interval. It is, indeed, only held in position by the nerve trunks that pass out from it through the intervertebral foramina, and by its connections with the theca. Above, it is connected with that part of the brain that lies upon the largest intracranial collection of the cerebro-spinal fluid (page 27), and it would appear that the most violent movements possible of the brain within the skull could be but very feebly communicated to the spinal cord. The cord, moreover, within its theca, is surrounded on all sides by a space occupied by cerebro- spinal fluid. It is difficult to understand, therefore, how a structure so protected can be so violently dis- turbed by a shock received ujoon the body as to undergo a grave and progressive loss of function. The cord is, indeed, somewhat in the position of a caterpillar sus- pended by a thread in a phial of water. It would probably be difficult to permanently disturb the in- ternal economy of such an insect (even if it had a structure as elaborate as the cord) by other than vio- lence that would be comparatively excessive. Contusion and crushing: of the cord. — As has been already observed, the gravity of fractures and dislocations of the spine depends upon the extent of the damage received by the cord. In these accidents it is very usual for some part of the injured vertebras to be projected into the spinal canal, so as to press upon or actually crush the delicate nerve centre that it contains. It is needless to observe that the cord is extremely soft, and thus it happens that it may be entirely broken up by violence without the membranes being percep- tibly damaged. Indeed, in fracture-dislocations it is unusual for the theca to be torn, and it is possible for the cord to be quite crushed at some one spot without the corresponding pia mater being in any way lacerated. 5IO Surgical Applied Anatomy. [Chap. xxiv. The amount of damage inflicted upon the cord will vary, of course, with the magnitude of the accident ; but, other things being equal, it will be found to be more severely injured in fracture-dislocations of the cervical and dorsal segments than in like lesions in the lumbar spine. In the atlo-axial region the amount of displacement that follows upon luxation of the two bones from one another is such that the cord is, as a rule, severely crushed, and death ensues instantaneously, as is seen in cases of death by hanging. In the cervical and upper dorsal segments of the column the vertebral bodies are small, the spine is mobile, the fractures met with in the parts are usually due to indirect violence, and are associated with much displacement. In the lower dorsal region, again, the greater rigidity of the spine renders any displacement, when it does occur, likely to be considerable. In the lumbar region, on the other hand, it must be noted that the cord only extends to the lower border of the first vertebra. The bodies of the vei-tebrse, also, in this district, are very large and cancellous, and can undergo a severe amount of crushing without a corresponding degree of dis- placement being produced. The part is also well protected by the large intervertebral discs, and by the immense masses of muscle that surround the spine in the loins. Such portion also of the spinal medulla as extends into the lumbar region is protected by the many cords of the cauda equina, which, by their loose- ness and comparative toughness, tend to minimise the efiects of violence. The degree of displacement of bone required to produce pressure effects upon the cord is often greater than would be supposed. At post-mortem examina- tions portions of injured vertebrae have been found encroaching upon the spinal canal to a considerable extent in cases where no evidences of damage to the cord existed during life. Dr. J. AV. Ogle reports the Chap. XXIV.] The Spine. 511 case of a man who, after an injury to the neck from a fall, presented no spinal symptoms until three days had elapsed. He ultimately became paralysed, and died thirty-two days after the accident. The autopsy revealed a dislocation forwards of the sixth cervical vertebra, of such an extent that the body below projected at least half an inch into the spinal canal. The remarkable manner in which the cord will accommodate itself to a slowly progressing pressure is often well seen in the results of chronic bone disease in the column. The symptoms due to injury to the cord and to the nerves contained in the spinal canal, will obviously depend from the situation and extent of the lesion. The diagnosis of the situation of the lesion is compli- cated by the relation the nerves bear to the various vertebrae, and by the fact that the majority of the great trunks arise from the cord at a spot above the point at which they issue from the vertebral canal. The two highest nerves, the first and second cervical, pursue an almost horizontal course in their passage from the cord to their points of exit from the canal. The remaining nerves take a more and more oblique direction, until at last the lowest nerve trunks run nearly vertically downwards as they pass to their respective intervertebral foramina. Points of exit. — The first cervical nerve leaves the canal above the first cervical vertebra. The remaining cervical trunks escape also above the vertebrae after which they are named, the eighth cervical nerve leaving the canal between the last cervical and the first dorsal vertebrae. The dorsal, lumbar, and sacral nerves have their points of exit below the vertebrae after which they are named. Thus, the first dorsal nerve will pass through the foramen between the first and second dorsal vertebrae, and so on. 512 Surgical Applied Anatomy. [Chap. xxiv. Points of Origin from the Cord. The first cervical nerve arises from the cord opposite the interval between the atlas and occiput. The second and third cervical nerves arise from the cord opposite the axis. The fourth, fifth, sixth, seventh, and eighth cervical ners'-es arise from the cord opposite the third, fourth, fifth, sixth, and seventh vertehrse respectively. The first four dorsal nerves arise from the cord opposite the discs below the seventh cervical and the first, second, and third dorsal vertebrae respectively. The fifth and sixth dorsal nerves arise from the cord opposite the lower borders of the fourth and fifth vertebrae. The remaining six dorsal nerves arise from the cord opposite the bodies of the sixth, seventh, eighth, ninth, tenth, and eleventh vertebrse. The first three lumbar nerves arise from the cord opposite the twelfth dorsal vertebra. The fourth lumbar nerve arises from the cord opposite the disc between the twelfth dorsal and first lumbar vertebrae. The last lumbar nerve, together with the sacral and coccygeal nerves, arise from the cord opposite the first lumbar vertebra. It will be seen, therefore, that in taking note of the symptoms due to crushing the entire nerve con- tents of the vertebral canal at a certain spot, con- sideration must be taken, not only of the effects of damaging the medulla at that point, but also of the result of lacerating nerve trunks that may issue there, although their origins are above the seat of lesion. The cord is also very often only damaged in part, or it may entirely escape, while one or more nerves are crushed by the fractured vertebrae, or by fragments of bone separated by the lesion. In fracture-dislocations the upper vertebral body, as already stated, usually glides forwards, with the result that the anterior and antero-lateral parts of the cord are brought into violent contact with the pro- tecting border of the vertebrae below the seat of lesion. Chap. XXIV. 1 The Spine. 513 It is in these parts of the cord that the main motor tracts run, and thus it happens that motion is more often lost in the parts below the site of the injury than is sensation. If there be partial motor and sensory paralysis, the disturbance of the former function is likely to be in excess of that of the latter. In no case, indeed, does there appear to have been a loss of sensation without, at the same time, some disturbance in the powers of movement. If the grey matter of the cord be not severely damaged, reflex movements appertaining to that segment of the cord can usually be induced in the paralysed parts by proper stimulation. If those reflex movements be lost, it may be inferred that the grey matter is broken up, and that the entire spinal medulla has been crushed at the seat of lesion. The higher up the fracture in the column the greater is the tendency for the function of respiration to be interfered with. If the lesion be at the upper end of the dorsal spine, then not only will all the abdominal muscles be paralysed, but also all the inter- costals. A fracture, associated with injury to the cord, when above the fourth cervical vertebra, is, as a rule, instantaneously fatal. The phrenic nerve comes off mainlv from the fourth cervical nerve, receivincf contributions also from the third and flfth. The fourth nerve issues just above the fourth cervical vertebra. If the cord be damaged immediately below this spot, the patient can bi-eathe only by means of the diaphragm, and if the lesion be so high as to destroy the main contribution to the phrenic, respi- ration of any kind becomes impossible. Certain disturbances of the act of micturition are frequent in cases of injury to the cord. The reflex centre for tliis act is lodijed in the lumbar enlarge- raent. The irritation of the vesical walls, produced by the increasing distension of the bladder, provides H H 514 Surgical Applied Anatomy, [chap. xxiv. the needful sensory impulse. This impulse is re- flected to the nerves controlling the bladder muscles, and especially to the detrusor urinae, and by their contraction the organ is emptied. The action, how- ever, can be to some extent inhibited by influences passing down from the brain to the lumbar centre, and the tendency to a frequent discharge of urine is resisted by contraction of the sphincter. When, therefore, any part of the cord is damaged that lies between the lumbar centre and the brain, this inhibi- tion can have no efiect. Immediately after the accident the temporary suspension of reflex actions from shock produces some retention of urine, and after that the bladder empties itself at frequent intervals, the patient being unconscious of the act, and unable to influence it. If the centre itself be damaged in the lumbar cord, the patient, after a little retention, will sufier from absolute incontinence ; and a like result will follow if the nerve connections between the cord and bladder below the spinal centre have been destroyed. The principal nerves connecting the medulla spinalis with the bladder are the third and fourth sacral. The act of defsecation also is apt to be disturbed in a like manner. Here there is, as in the previous case, a reflex centre in the lumbar enlargement, with motor and sensory nerves connecting it below with the rectum and its muscles ; and also between this centre and the brain are tracts, but little known, along which inhibitory actions can extend. When the centre itself is damaged, or the con- nection severed that unites it with the viscus, the patient will sufier from incontinence of f feces, and will be unable in any way to control the act. When the cord is damaged at any spot between the centre and the brain, then the act of defaecation will be performed at regular intervals, without either the c'i:ip. xxiv.i 'The Spine. 515 patient being conscious of the act or being capable of inhibiting it. In some injuries to the cervical cord the patient has suffered from severe vomiting for some time after the accident, or has exhibited a remarkable alteration in the action of his heart. Mr. Erichsen, for example, reports the case of a man who, after a severe blow upon the cervical spine, continued to vomit daily for several months. In the other category, instances have been recorded when the pulse has sunk as low as 48, or even as 36, and 20, after lesions to the column in the neck. These changes are supposed to be due to dis- turbance of the vagus, and it is further suggested that the morbid influence is conveyed to the vagus by the spinal accessory nerve with which it is so freely associated. It should be remembered that the spinal accessory trunk has origin from the cord as low down as the sixth or seventh cervical nerves. INDEX. Abc^s en. bissac, 467. Abdomen, Blows on the, 267. , Congenital deformities of the, 277. , Emphysema of wall of, 267. , Nerves of the, 273. , Prutuberance of the, 262. , Skin of the, 265. , Sxirface anatomy of the, 262. , Wounds of the, 272. "Abdominal belt," 266. connective tissue and ab- scesses, 271. muscles, Ei^dity of the, 274. parietes. Anterior, 265, 267. , Posterior, 2S0. ring, external, Feeling for the, 279. wall, nerve associations, 274 Abnormalities in skull, 16. Abscess about axillary region, 182. about cervical region, 127. , Gluteal, 383. , Iliac, 291. in antrum, 81. in mastoid cells, 67. in meiliastina, 160. in testis, 370. in the abdominal parietes, 271, 291. in the female breast, 153. in the scalp, 5. in the temporal fossa, 8. Ischio-rectal, 347. Lumbar, 295. Orbital, 36. Palmar, 245. Parotid, 62, 88. , Opening of, 91. Pelvic, iu hip joint, 397. Perinepbritic, 328. Peritvphlitic, 296, 311. Popliteal, 430. Post-pharyui,'eal, 114. Prostatic, 360. Psoa.=!, 293, 392. Kenal, 328. , Thecal, 248. Accelerator urinse, 346. Acetabuhim, 396. , Fractures of, 338. Aching legs from standing, 455. Acne hji)ertropbica, 71. Acromial vault, 189. Acromio-clavicular joint, 176. , Dislocations of, 177. -thoracic artery, 166. Acromion process. Fracture of, 179. Addison's disease, 332. Adductor longus muscle, 389, 393. Air in veins, 143, 185, " Alderman's nerve," 64. Alexis St. Martin's case, 301. Amputation (see Arm, Ami»utatiou of, etc.). Anal triangle, 344. Anastomotica magna, 426, 428. Anatomical neck of humerus, fracture, 199. Anchylosis at the shoulder-joint, 193. at the sterno-clavicular joint, 174. Aneiirism, Aortic, 143, 333. , AxiUary, 186. in the neck, 143. of the posterior tibial artery, 45t. , Popliteal, 432. Ankle and fibula, relations, 475. and foot, 461. , Surface anatomy of, 461. joint, Amputation at, 490, 491. , Disease of, 473. , Dislocations at, 474. , its movements, 473. line, 462. , Referred pains in, 474. Annular litraments of ankle, 468. of wrist, 246, 248. Anosmosia, 79. Anterior crural nerve, 394. , Paralysis of the, 493. , Strength of the, 387. Antero-posterior arch of the foot, 479. Antrum of Highmore, 76, 81. Anus, 344, 376. in violent defsecatiou, 377. 5i8 Surgical Applied Anatomy. Aorta, Abdomiual, 264, 333. , Thoracic, 140, 143, 159, Aortic orifice, 159. Aponeuroses (see Fasciae). Aqueduct of Faliopius, 67. Aqueous humour, 51. Arachnoid cyst, 26. , The, 26, 506. Arcus senilis, 41, Arm, 202. , Amputation of, 209. , Issue on, 205. , Skin of the, 204. , , Ecchymosis in th.e, 204. , Surface anatomy of the, 202. Arnold's nerve, 64. Arteria centralis retinse, 46. Arteries (see Axillary, etc., and Blood-vessels). Arterio-venous aneurisms, 37, 215, 393. Arthritic nail, 243. Astragalo-scai^hoid articulation, 462, 483. Astragalus, Fractures of, 488, , Dislocations of, 481. Atlas, Disease of, 114. Atlo-axial portion of spine, 500. Auditory meatus, External, 59. , its i-elations, 62, Auriculo-ventricular orifices, 159. Avulsion of the fingers, 257. Axilla, 165, 181. , Suspensory ligam.ent of, 182. Axillary abscess, 182. ■ artery, 165, 186. glands, 165. , Removal of, 185, nerves, 187. vein, 185. Axis, Disase of, 114. Azygos veins, 161. Barbadoes leg, 396. Bartholin's duct, 102. Base of skull, Fractures of, 22. Belly-ache and spinal disease, 275. Bend of elbow, 210. Bent arm after venesection, 215. Biceps tendon in arm, 191. in ham, 431. Bichromate disease, IQ. Bicipital groove, 164. Bifurcation of the aorta, 264. Bile duct, Eupture of the, 321. Bladder, Distance of the, from the surface, 352, , Distension of, 353. , Double, 358. Bladder, Extroversion of the, 278. , Fasiculated, 357. , Female, 358. , Foreign bodies in, 359. found in hernise, 355. , Male, 353. , Mucous raembrane of the, 357. of child, 359. , Puncture of above pubes, 3j3. , , per rectum, 355. relations to the peritoneum, 355, , Eupture of the, 356. , Sacculated, 358, stabbed through buttock, 388 Blisters to knee, Effect of, 428. Blood-vessels in the abdominal vralls, 272. in foot and ankle, 470. in Scarpa's triangle, 393, of .auditory meatus, 63. of brain, 32. of breast, 154. of buttock, 385. of face, 83. of foot, 470, of globe, 45. of hand, 240, 249. of heel, 491. of knee, 428. of nares, 78. of neck, 142. of orbit, 37. of pinna, 63. of rectum, 376. of scalp, 9, of the abdomen, 333, of the soft palate, 112, of tympanum, 70. Brachial aponeurosis, 204. , Principal structures re- lated to, 205. artery, 205, 216. , Compression of, 206. in phlebotomy, 215. , Ligature of, 206. plexus, 122, 258. , Injuries to the, 131, 258 — , Strength of the, 387. Bracbialis anticus, 205. Brain, 31. and skull relations, 29, , Blood-vessels of the, 32. , Compression of the, 25. , Concussion of the, 32. Index. 519 Brain, Congestion of the, neu'ra- lised, 28. , Fissures of the, 29. injuries, 27, 32. , Membnmes of the, 25 , Motor centres of, 31. BranoLial fistulre. 59, 14tj. Brasdor's operation, 143. Breast, Tbe female, 153. Bregma, 12. Brocas convolution, 30. Bronchi, 131. 141. 157. , Foreign bodies in, 137. Bronchocele, 138. Brunner's glands in burns. 308. Bryant's method of dividing the muscles of the palate, 112. Buccal cavity, 102. in foetus, 110. nerve, 87. Bulbous urethra, 364. Bunions, 469. Bursaj about the foot, 468. about the ham, 433. about tlie shoulder, 190. between the patella ligament and the tubercle of the tibia, 429. between the quadriceps and the femur, 42';>, 436. of the elbow, 217. • over the great trochanter, 385. over the ischial tuberosity, 385. over th« knpe joint, 429. , Patellar, 429. , Subacromial, 187, 190. Buttocks, Arteries aud nerves of the, 385. , Surface anatomy of the, 38^. Button-hole action of tbe sesamoid bones and their tendons, 257. Caecum, 311. , Foreign bodies in the, 311. in intestinal obstruction, 312. Caesarian section, 338. Calcaneo-iisti-agaloid joint, 480. cuboid articulation, 483. scaphoid hgament, 462, 483, 486. Calcar femorale, 406. Canal of Nuck, Hernia in, 285. of Schlemm, 51. Cancer of gullet, 141. Caucrum oris, 83. Capsule of Tenon, 35. Carbuncle on tbe neck, 12:3. Cardiac orifice of stomach, 299. Caries siccw, 68. Curious teeth, Efifecta of irritation caused by, 99. Carotid artery, 120, 142. , Aneurism of, 143. destroyed by abscess, 128. , Ligature of, 142. , Wounds of, 130. tubercle, 119. Castration, 371. Cataract, 50. , soft, Treatment of, 52. Catheterism of Eustachian tube, 69. of urethra, 362. Centre of gravity of an adult body, 336. Cephalboematomatn, 7. Cerebral localisation, 30. Cerebro-spiual fluid, 28, 506. Cervicul cord injimes aud vomit- ing, 515. sympathetic. Paralysis of, 39. Cervico-dorsal piut of spine, 500. Charbon, 83. Cheek, Substances embedded in, 83. Chemosis, 56. Cholecystotomy, 322. Chopart's operation, 491. Chorda tympani nerve, 70. Choroid, 42. Ciliary zone, 45. Circulus major, 45. minor, 45. Circumcision, 365. Cix'cumcomeal Z"ne, 46. Circumflex artery, external, Rup- ture of, 420. , internal, "Wound of, 420. , Posterior, 166, lb8. — — nerve, 106, 188. Cirsoid nu'-nrism, 10. Clavivle, 162, 166. , Dislocations of, 175, 177. , l>'ractures of the, 169. , Green-stick fracture of the, 171. , Movements of the, 173. , Ossiti cation of the, 172. , Relations of. 171. , Removal of the, 168. , Structures behind the, 167. Cleft palate, 109. Clergvman's sore-throat, 132. Club-foot, 483. 520 Surgical Applied Anatomy. Coccygeus, 34Q, 341. Coccygodyiiia, ?A). Cochin leg, 396. Cceliac axis, 265. Colectomy, 317. CoUes' fracture, 252. Coloboina iridis, 44. Colon. 310. , Oonaenital nialfonnation of the, 314', , Stricture of the, 312. Colotomy, 315. Compression of brain, 25. of cord, 507, 509. Concretions in the caecum, 312. Concussion of brain, 32. of cord, 508. Conditions lessening the danger of blows upon the skull, 19. Condyle of the elbow. External, 211. . , Internal, 211. of the femur, Inner, 425. , Outer, 425. Condyles of femur, Condition of, in knock-knee, 441. , Fracture of, 446. of humerus, Fracture of, 222. Congenital club-foot, 484. exomphalos, 278. fistulse, 59, 146. hernia, 283. hydrocele, 283. malformations of anus and rectum, 377. of bladder, 278. of colon, 314. of penis, 366. tumour of stemo-mastoid, 121. Conjunctiva, 56. Conti-auted knee and anchylosis, 435. Contre-coup, Fracture by, 22. Convolutions of brain. Motor centres on, 30. , Relations of, to skull, 29. Coraco acromial arch, 189. ligament, 164. brachialis muscle, 203. Coracoid process. Fracture of the, 179. Cord, Spinal, 505. , Concussion of, 508. , Contusion of, 509. , Injuries to the, symp- toms of, 511, Cornea, 40. Corneitis, Seat of pain in, 47. Coronal suture, 12. Coronoid process, fracture of the, 225. of the ulna, 211. Corpus striatum, 30. Coryza, 74. Costo-coHc fold, 324. coracoid membrane, 182. Coup de fouet, 4.53. Cranial contents, 25. — — sutures, 12. Cranio-tabes, 13. Cranium, Bony vault of the, 12. Creases in the skin of the palm, 239. on abdomen, 265. Cremaster muscle, 370. Cremasteric artery, 370. Cribriform plate, 73. Cricoid cartilage, 118, 119, 131, 132. Crico-thyroid space, 119, 137. Crural canal, 286. Crushing the si>inal cord, 509. Crutch paralysis, 207. Cuboid bone, 462. Cuneiform, bone. Inner. 462. , , Dislocation of the, 488. , , Fracture of the, 488. Curves of the vertebral column, 497. Cyphosis, 497. Dacryops, 58. Dangerous area of the scalp, 2. Dartos, 266, 367. Defagcation and the seminal vesi- cles, 373. Deltoid muscle. Insertion of the, 203. region, 187. tubercle, 162. Dental foramen, 86. Digital arteries, 240, 249. Diploic veins, 11. Discs, Intervertebral, 498. Dislocation (see the several bones and joints). Distension of the bladder, 353. of the intestines, 310. of the rectum, 374. Distinguishing large bowel from small in lumbar colotomy, 317. Diverticula from the synovial membrane of the shoulder-joint, 192. Index. 521 Dorsal surface of the baud, 240. vein of peuis, 3 19. Dorsalis pedis artery, 471. scapulae artery, 1(36. Dorso-luuibar i>art of spine, 500. Double chiu, 123. Drop wrist, 2.">8. Duodenum, 305. Dupuytren's coutraction, 241. fracture, 477. Dura mater, 25, 506. , Fungus of, 26. Dyapbonia clericoi urn, 132. Ear, Abscess of, 61. , Bleeding from, in fractures of base of skull, 23. , Blood-supply of the, 63, 70. -coughing-, 6t. , External, 59. , Foreign bodies in, 62. , Gangrene of, 63. , Haematomata of, 63. , Nerves of, 63. , P<->lypi of, 62. -rings in eye disease, 65. , Slits in, in scrofula, Q/^i, sneezing, 64. , Tophi in, 60. yawning, 64. Earache and toothache associa- tions, 65. Ectropion, 54. E.jaculatory ducts, .363. Elbow. Disease of the, 218. , Dislocations of the, 219. , Fold of the, 210. -joint, 216. , Rigidity of, 219. , Ligaments of the, 217. , Region of the, 213. , Rejection of the, 225. . Surface anatomy of the, 210. Elephantiasis Arabtim, 395. in the labia m'ajora, 372. Emboli in cerebral arteries, 33. in left carotid artery, 143. Emissary veins of skull, 10. Encephalocele, 15, 73. Encysted calculi, 358. hydrocele of the cord. 2^3. End-bulbs in the nerves of the foot, 466. Enlarged spleen, 32 i. Enostoses of frontal sinuses, 80. Enterotomy, 309. Entropion, 57. Epicondyle of humerus, 223. Epigastric artery. Deep, 265. Epiphora, 58. Epiphyses of acromion, 179. of pelvis. Separation of, .3-37. , upper, of the femur. Separa- tion of the, 408. Epiphysis, Lower, of femur in ex- cision of knee, 449. , , in knock-knee, 441. , , , Separation of, 4t6. , , of humerus, Separ.ition of, 224. , -, of radius, Separation of, 255. , , of tibia. Separation of, 458. of clavicle. Separation of, 172. of coraooid process, 179. of olecranon, 225. of third phalanx in whitlow, 248. , upper, of humerus. Separa- tion of, 200. , , of tibia, Separation of, 443. Epispadias, 366. E[jistaxis, 78. E pithelinmata of the scrotum,366. Erector spinaB muscles, 261. ' Eustachian catheter. To pass, 69. tube, 68. Excision (see special parts). of the tongue, 108. Extensor carpi ulnnris, 236. communis digitorum, 236. longus digitorum, 463. poUicis, 463. ossis metacarpi pollicis, 235. primi intemodii pollicis, 235. secundi internodii pollicis, 236. External auditory meatus, 60. Extracapsiilar fracture of the fe- mur, 407. Extravasation of urine, 266, 340. Eye-ball, 40. , Blood supply of the, 45. , Dangerous area of, 49. , Nerves of the, 47. Eyelids, 54. , Layers of the, 55. Face, 82. , Extensive injuries to, &4. , Nerves of the, 85. Facial artery, 84, 121, nerve, 90. 522 Surgical Applied Anatomy. Facial neuralgia, 11, 85. paralysis, 58. vein, 85. Faeces, Incontinence of, in spinal injuries, 514. Fascia, Axillary, 182. , Bicipital, 215. , Cervical, 124. , Clavi-pectoral, 182. , Iliac, 290. in region of Scarpa's triai gle, 391. lata, 392, 419. luniborum, 295. in lumbar colotomy, 315. ■ , Obtirrator, 342. of arm, 204. • of buttocks, 383. of Colles, 348. of deltoid reg'on, 187. of foot, 463, 466. of leg, 452. of paim, 242, 244. of the scalp, 7. , Parotid, 88. ■, Pectoral, 182. , Pelvic, 341. , Perineal, 348. , Popliteal, 430. , Prevertebral, 127. , Eecto -vesical, 342. , Temporal, 7. , Transversalis, 290, 315. Fasciculated bladder, 357. Fatty tumours about face, 83. Female bladder, 358. . breast, 153. rectum and vagina, 374. Femoral artery. Ligature of, 420. Femur, Dislocations of the, 409. fractures of, 405, 421, 446. , , and shortening of limb, 422. Fenestra ovalis, 67. • — — rotimda, 67. Ferguson's method of dividing the miiscles of the palate, 112. Fibula, fractures of, 458. 475. , Head of the, 425, 450. Fibular shaft. Lower half, 451. Fissure of Eolanrlo, 29, 31. Fistula at the navel, 270. between the gall bladder and gut, 313. in ano, 347. , Lachrymal, 58. , Salivary, 92. Flat-foot, 485. Flexing of the thigh in hip disease, 399. Flexor carpi radialis tendon, 235. ulnaris tendon, 286. longus digitorum, 463. pollicis pedis, 463. — — sublimis tendons, 236. Fold, Gluteal, in hip disease, 381. Fontanelle, Sagittal, 17. , Fontanelles, 12. Foot, Amputations of, 490, 491, 492. , Arches of the, 479. , Blood vessels of, 470. , Chief joints of the, 480. , Dislocations of, 474, 481, 482, 488. , Fasciae of, 466. , Fractures of, 487. , Integuments of, 465. , Lymphatics of, 472. , Nerves of the, 465. , Surface anatomy of, 461. , Synovial membranes of, 483. , The, 461, 479. Foramen of Magendie, 28. of Monro, 28. Fore-arm, 227. , Amputation of the, 234. -, Bones of the, 229. , Fractures of the, 231. , Luxations of the, 219. — — , Surface anatomy of the, 227. , Vessels of the, 228. Fossa, Ischio-rectal, 344, 345. , Nasal, 73. , Subclavicalar, 164. of Eosenmiiller, 69. Fracture (see the several bones). dislocation of the vertebral column, 503. MHcoide, 458. Fraenum linguae, 105. Frontal sinus, 80. Fungus of the dura mater, 26. of the testicle, 370. Gall bladder, Eiipture of the, 321. , Fundus of, 318. , Ulceration of the, 313. stones, 321. Gangrene of nose, 71. of pinna, 63. of the leg and embolism, 454. Garters and the saphenous vein, 454. Gasserian ganglion, affected by abscess spreading from parotid, 90. Index. 523 Gastric fistula, 301. Gastrocnemius imiscle, 451. , Rupture of the, 453. Gastrostomj', 303. Gastrotomy, 303. Geuerative or^aus, Female, 372. Geiiito-crural nerve, 370, 394. Geuu-valjjum, 440. , Three stsiges of, 441. Gladiolus separated from manu- brium, 148. Glandular larjii^tis, 133. Glans penis, 365. Glaucoma, 42, 53. (Tlaucomatous cup, 54. Glottis, 132. , (Edema of, 132. Gluteal abscess, 383. aneurisms, 385. artery, 385. bursse, 385. region, 380. Gluteus maximus, 384. , Kupture of, 384. Goitre, 138. Granulai- lids, 57. Great trochanter, 380. Groin, Eegion of, 388. Gullet, 139. , Foreign bodies in the, 110. , Operations on, 141. Guma, 104. Gustatory nerve. Moore's method of dividing the, 103. Haematomata of scalp, 6. on septum nasi, 77. on the pinna, 63. Hsematuria after injury to back, 328. Haemophysis, 157. Haemorrhage, Extra-meningeal, 25. from choroid, 43. from fraenum linguae, 105. from intercostal vessels, 152. from tongue, 106. from tonsil, 117. in lithotomy, 350, 352. into subdural space, 26. into vitreous, 47. in tracheotomy, 136. Hsemorrhoidal vessels and nerves, 347, 376. Haemothorax, 157. Hamstring muscles, 418, 4.30. Hiunular process to be felt. 111, Hand, 237, 241. ■ , Amputation of, 257. Hand, Blood-vessels and lym- phatics in the, 240, 249. , Dislocations of, 255, 256. , Fasciae of, 244. , Surface anatomy of, 2.37. , Synovial sheaths of, 247. Hanging, Mode of death from, 510. Hard palate, 110. H:ire-lip, 109. Heart, its relation to the surface, 157. , Wounds of the, 1.59. Heel, Integuments of, 491. Hplicoidal fractures of Leriche, 422. Hemiplegia, 33. Hernia, Congenital, 283. , , disposition to, 284. , Diaphragmatic, 290. , Direct, 280. , uersus indirect, ingui- nal, 281. , Kncysted, 2&3. , Femoral, 286. , Infantile, 283. , Inguinal, 278, 284. into the funicular process, 283. , Lumbar, 289. , Mesenteric, 298. , Meso-colic, 298. , Obturator, 288. , Perineal, 289. , Pudendal, 289, 372. , Rare forms of, 289. , Sciatic, 289. , Structures related to fem- oral, 287. , UmbiUcal, 289. , , Congenital, 269. , Vaginal, 372. Herniotomy, 285. Herpes labialis, 100. zoster of face in association with eye att'ections, 48. Hip disease and pain in the knee, 403. dislocations of, 409. joint, .396. , Amputation at the, 415. disease, 398. , Fractures about, 405. movements of, 397. , Region of the, 3S0. Hippocratic hand, 243. Holden's Line, 388. Hottentot Venus, 383. Human tails, 340. 524 Surgical Applied Anatomy. Hamerus, Dislocations of, 193. , fractures of, 199, 207, 223. , , nou-union after, 208. Hydatid cyst in tlie liver, 321. Hydrencephalocele, 15. Hydrocele, 369. of the neck, 146. Hydrocephalus, 13, 28. Hyoid bone, 119. , Fracture of, 131, Hypertrophy of the prostate, 360. Hypopyon, 52. Hypospadias, 366. Hypo thenar emineuce, 237. Hysterical hip, 404. knee, 404. Ichthyosis linage, 105. Ileo-csecal valve, 308. He am, 305, 308. Ihac abscess, 291. fascia, 290. Iho-psoas muscle, 290, 392. tibial band, 384, 419, 425. Indh-ect hernia, 280. Inequality of liujbsin length, 423. lufautile hernia, 283. Interior dental nerve, Dividing the, 86. maxilla, Dislocations of, 97. , Excision of the, 98. , Fracture of the, 95. thyroid veins, 119, 129, 136. Inflammation of the viscera and blood-lettings, 334. Infraorbital foramen, 86. nerve, 86. Inguinal canal. Female, 284. Innominate artery, 143, 159. bone, 335. Intercostal artery, Wounding of the, 152. spaces, 151. Internal carotid artery, 67,115,117. jugular vein, 67, 115, 117. mammary artery, 152. popliteal nerve. Strength of the, 387. Interstitial keratitis, 41. Intervertebral discs, 497. and fracture-dislocation, 504. Intestinal calculi, 312. Intestine, Diverticulum from, 308. , Foreign bodies in, 309, 311. ■ , Large, 310. , Kesectiou of, 310, 317. , Euijture of, 307. Intestine, Small, 305. Intestines, Wounds of, 306. lutracai^sular fracture of the femur, 405. Intussvisception, 309, 310. Inversion of the testicle, 339. Iridectomy, 44. Iridodyalisis, 44. Iris, 43. Iritis, Seat of pain in, 47. Iscbio-rectal fossa, 34i, 346. Isthmus of thyroid, 135. , Division of, 136, 138. Jacob's ulcer of the eyelid, 55. Jaws (see Inferior and Superior Maxilla). Jejunum, 305. Joints, Surgical classification of the, 189. Keloid, its frequent seat, 148. Kidney, 326. , Hilus of the, 326. , Horse-shoe, 329. , its relations, 326, , Movable, 329, , Operations on, 330. , Rupture of the, 328. vessels. Point of origin of, 265. Knee, Blood-supply of the, 428. , Bursse about, 429, 433. , Dislocations of the, 445. , Fractiu-es about, 443, 447. , Integuments of, 427. joint, 435, , Amputation through the, 449, — , Disease of, 437. , Excision of the, 448. , Mobility of the skin over the, 427, pains and sigmoid flexure,332, , Region of, 424. , Surface anatomy of the, 424 Knock-knee, 440. Labia majora, .372. Lachrymal abscess, 58. apparatus, 58, canals, 58, gland, 58. sac, 58. Lachrymation from irritation of nasal nerve, 48, 79. Lacuna magna, urethal, 364. Lambda, 12. Lambdoid suture, 12. Index. 525 Lamina cril^rosa, 54. fi.sca, -ti. suprachoroidea, 43. Laparotomy', 309. Larviigotomy, 133, 137. l.aryi.x, 131. • , Foreiga bodies in the, 137. , Fracture «f, 132. , Mucous membrana of the, 132. , Eemoving the, 133. , Submucous tissue of the, 132. Lateral htbott.my, 349. Left carotid artery, 159. innominate vein, 159. Leg, 450. , Amputation of the, 459. , Fasciae of, 452. , Fractures of the, 4"6. pain and diseased rectum, 4^)6. , Kickets affecting bones of, 459. , Skin of the, 452, , Surface anatomy of the, 4?0. , Vessels of, 453. Length of lower hmbs, 413. Lengtheninff of the limb in hip disease, 399. Lens, 50. Leucsemic enlargement of the spleen, 324. Levator ani, 341, 345, 346. , relation to fistula in ano, 347. palati. 111. palpebrse, 55. Ligamentum patellae, 425, 437, 444. pectinatiim iridis, 51. Lighterman's bottom, 385. Liiiea alba, 2fi3, 268. semilunaris, 263. Lingual artery, 121. Lipomata iu deltoid region, 1S7. in neck, 123. in Scarpa's triansrle, 391. on the buttock, 383. rare on face, 83. , Seat of, 187. Lips, 100. Ijisfrauc's ampittation, 492. Lithotomy, Lateral, 349. , , in childreu, 351. , , Parts divided iu, at9. , , that may be wounded, 350. , Median, :351. , versus lateral, 351. Littre's operation, 313. Liver, 318. Liver, Absci^sses of, 321. iu pyaemia, 321. , Piece of, forced into heart, 319. , Protrusion of, 319. , Pus from, discharged by bronchi, 321. , Relations of, 318. , Euptures of, 318. , Wounds of, 319. Lockjaw, 100. l>ordosis of the spine in hip disease, 400. Lower limb, Nerve supply of, 493. Lumbar colectomy, 317. colotomy, 315. fascia, 295. region, 294. spine, 498. , Injuries to, 409, 502, £01, 505, 514. Lung, 155. and secondary deposits, 157. , Relations of to sui'face, 155. , Rupture of, 157. , Wounds of, 156. Lvipus erythematosus, 71. Lymphangioma cavernosum, 107. Lymphatic glands and vessels (si;e each region). Macro-glossia, 107. Malar bone, 87. , Fracture of, 87. Malleoli, 461. , Fi-actures of, in dislocations of the foot, 475. Mammary abscess, 153. gland, 152. , blood-vessels and nerves of, 151. in groin, 391. Manubrium, 148. Masseter, 9, 100. Mastoid cells, 67. Maxillae (see Inferior and Supe- rior). Meatuses of nose, 76. Meatus, Walls of the auditory, 62, 63. Meckel's diverticulum, 270, 308. Median basilic vein, 211, 213, 214. , why selected for venesection, 214. cepVialic vein, 211, 213. lithotomy, 351. nerve, 229. , Paralysis of the, 260. Mediastina, 160. 526 Surgical Applied Anatomy. Mediastina, Abscess of, 128, 160. Medio-tarsal joint, 462, 483. , Amputation at, 491. Meibomian glands, 55. Melanotic growths of choroid, 43. Membrana tympani, 65. , Perforation of, 66. Membranous uretba, 349, 363. Meningeal artery, 8. Meninges of brain, 25. ■ of spinal cord, 503. Meningites (spinal) from bed- sores, 501. Meningitis from, abscess in the ear, 62. Meningocele, 15, 73, 75. Mesenteric arteries, 265, 333. Mesentery, 297. Meso-csecum, 311. nephron, 329. Metacarpo-phalangeal joint of thumb, dislocations at, 256. Metatarsal bone of great toe, Am- putation of, 494. bones. Fractures of the, -188. Metatarso - phalangeal articula - tions, 432. joint of thumb, Dislocation at, 489. Micturition and spinal injurie-, 513. Miner's elbow, 217. Motor centres on the cortex, 30. paralysis in injuries to cord, 513. Mucous polyp of nose, 77. Mumps, 91. Mnscae volitantes, 53. Muscles of mastication, 100. Muscular coat of tbe bladder, 357. Masculo-spiral nerve, 206. , Paralysis of the, 258. Nail, 2 13. Nares, Anterior, 73. , Posterior, 74. Nasal bones, 72. , Fracture of, 22. cavity, 73, 78. douche, 85. duct, 76. floor, 77. fossae, 75. mucous membrane, 77. nerve and orbital conuections, 48,71. polypi, 77. ■ septum, 76. sinuses, 80. Neck, 118. , Abscess of, 127. , Fascise of, 124. , Great vessels of, 142, , Hydrocele of, 146. , Integuments of, 122. , Lymphatic glands c»f, 144. , Middle line of the, 119. , Surface anatomv of the, 118. , Wounds of the,"l29. Necrosis of skull, 17. Nelaton's line, 381. Nephrectomy, 330. Nephrolithotomy, 330. Nephroraphy, 330. Nephrotomy, 330. Nerve-stretching, 387. supply of lower limb, 493. of ujDper Umb, 260. Nerves (see various regions). , Division of (see vario is trunks). of the spinal cord, their points of exit, 511. Neuralgia, Facial, 11, 85. Nipple in groin, 39 L of the female breast, 154. Nose, 70. , Cartilagmons part of, 72. , Nerve supply of, 79. , Outer wall o% 76. Notch of Eivini, 66. Obturator hernia, 288. nerve. Paralysis of the, 49t. or thyroid dislocation, 409. Occipital bone at birth, 15. , Necrosis of, causing wasting of tongue, 106. Occipico-frontalis, Suppuration under, 5. CEdema of the glottis, 132. CEsophagostomy, 141. (Esox)hagotomy, 141. (Esophagus, 139. Olecranon, 212. , Fractures of the, 224. Omental sac, 297. Omentum, Great, 297. Omo-hyoid muscle, 120. Onychia. 213. Onyx, 40. Ophthalmia, Sympathetic, 40. Optic disc, 50. neuritis, 51. thalamus, 30. Ora serrata, 50. Orbicularis palpebrarum, 55. Orbit, 33. Index. 527 Orbit, Fascire of. 35. , Fractiire of, 34. , Pulsating tuiuoiirs of, 37. Orbital al>scess, 36. arteries, 37. cavity, Bones of the, 34, ecchymosis, 87. fat, Foreign bodies in, 36. nerves, 37. walls, 34. Os calcis. Dislocations of the, 481. , Fractures of the, 487. , Tuberosity of, 461. 6pactal, 16. incisivum in hare-lip, 109. innominutiTm, 310. magnum, Dislocation of the, 253. Otitis externa, 62. Pacinian bodies in tbe liaul, 241. in the foot, 466. Palate, 108. , Cleft of, 109. , Hai-d, 110. , in idiots, 109. , Soft, 111. Palmar (.-:ce Haul). Palniaris longus tendon, 235. P.mcreas, 325. Panuiis, 41. Paracentesis of the pericardium, 160. of thorax, 151. of tjnnpanum, 66. of ventricles of braiu, 13. Paralysis in spinal injuries, 509, 513, 514, 515. ■ of anterior crural nerve, 493. of cervical symi.iathetic, 39. of external popliteal nerve, 496. of great sciatic nerve, 496. of internal popliteal nerve,496. of median nerve, 260. of musciilo-spiral nerve, 258. of obturator nerve, 494. of orbital nerves, 38. of ulnar nerve, 260. Pai'ietal tissures, 16, 17. Parieto-occipital fissure, 29. Paronychia, 243. Parotid abscess, 88. fascia, 88. gland, 88. , Structures in, 90. region, 87. tumour, 91. Patella, 424, 442. Patella dislocation, 444. Patellar ligament, 425, 437, 444. Pelvic arch, 335. cellulitis. 342. fascia, 341. symphysis, 338. Pelvis, 334. , Floor of the, 341. , Fractures of, 3.37. , Mechanism of, '34. Penile urethra, 364. Penis, 365. Perforating ulcer, 466. Pericrauiuui, 4. Perinea] hernia, 289. vessels and nerves, 3lr7. Piriuephritic abscess, 3-8. Perineum, Depth of, 346. , Fasciae of, 348. , male, 344. Peritoneum, 295. Perityphlitis, 311. Peroneal artery, 451. —' — tubercle, 462. Peroneus tertius, 463. P'^tit's triangle, 264. Phantom tumour, 270. Pharynx, 112. , Foreign bodie=! in, 11.^. , Mucous membrane of, 114. , Eelations of, 114. Phlebolithes, 361. Photophobia, 48. Phrenic nerve, 122. 332. Pis:eon breast, 147. Piles, 376. Pinna, 59. Pirogoff's amputation, 491. Plantar (stv Foot). Plantaris tendon, Rupture of, 453. Plaques des fumeurs, 105. Platysma myoides, 122. Pleura, 1.55. Pneumatocele, 68. Pueumo-thorax, 156. Politzer's method of inflating the middle ear, 68. Pollock's metbod of dividing the muscles of the palate, 112. Polypi of nose, 71. Popliteal abscess, 4;?0. artery, 426, 431, 451. b\irs8e, 433. fascia, 430. glands, 427, 433. nerves, 426, 427, 496. space, 425, 429. vein, 432. 528 Surgical Applied Anatomy. Pott's fracture, 477. Poulticing the loin in nephritis, 33 i. Profunda arteries in arm, 203. • femoris, .390. Prolajisus ani, 373. Pronator radii teres, 210. Prostate, 349, 359. , Abscess of, 360. , Hyi^ertropLy of, 360. Prostatic plexus of veins, 361. Psoas ahscess, 293. muscle, 290, 392. Pterioij, 12, 29. Ptosis, 38. Puhic spine, 263. Pudendal hernia. 289 372. Pudic vessels and nerves, 346. Pulmonary apoplexy, 157. artery, 158. Puncta lachrymalia, 58. Puncturing the hladder per rec- tuxii, 355. Pylorus, 299. , Eesection of the, 303. Rachitic nail, 243. Radial artery, 228. nerve, strength of the, 387. vein in venesection, 215. Radius, Dislocations of the, 220, 222 — , 'Fractures of the, 225, 232,252. Ranula, 102. Rectocele, 372. Recto-vaginal fistula, 372. Rectum, Adult, 373. , Attachments of the, 375. , Effects of distension of, 374. - — , rorei<^n bodies in, 374. , Infant, 373. ,Introductionof handinto,374. , Mucous membrane of the, 375. , Serous membrane of the, 373. , Vessels of, 376. Rectus abdominis muscle, 270. femoris, 417. Itesection of the small intestine, 310. Resections (see the various parts). Respiration iu fracture of the s]iine, 513. Retina, 50. Rhiuoiithes in the nose, 11. Rhinoplasty, 9, 204. Rhinoscopy, Posterior, 74. Ribs, 149. , Fractures of, 149. Rickets, Effect of, on pelvis, 336. , , on the ribs, 151. , , on the skull, 13. , , on tibia, 459. Rider's bone, 393. sprains, 393. Right auvicle. 159. Rima glottidis, 119, 132. Rouge's operation, 73. Sacculated bladder, 358. Sacro-coccygeal joint, 340. -iliac synchondrosis, 335, 339. Sacrum, 335. , Dislocation of the, 339. Sagittal fontanelle, 16, 17. Salivary fistulse, 92. Saphenous openintr, 390. veins, 418, 426, 433, 452, 454. Sartorius muscle, 389, 392, 420. Scalene muscles, 120, 123. Scalp, Dangerous area of, 2. , its mobility, 3. , Suppuration in the, 6. , Vascularity o? the, 4. wounds, 3. Scaphoid bone. Dislocation of the, 488. tubercle, 237, 461. Scapula, 164, 178. , Fractures of, 179. , Removal of, 180. Scarpa's triangle, .388. , Fascia of. 391. , Glands of, 394. , Vessels of, 39^. Sciatic nerve. Great, 386. , , Course of the, 382. , , Paralysis of the 493. , , Strength of the, 387. Sciatica, 386. Sclerotic, 42. Scrofula, Sign of, in pinna, 60. Scrofulous pharyngitis, 114. Scrotum, 366. and elephantiasis, 367. and oedema,, 367. , Application of leeches to the. 367. . Subcutaneous tissue of the, 367. Semilunar cartilages of knee, Dislocation of the, 439. Semi-membranous tendon,426,430. Septum crurale, 286. Shortening of the limb in hip dis ease, 401, 403. Index. 529 Shoulder, Bursse about, 190. , Dislocations of the, 193. , Fractures about the, 199. joint, 189. , Amputation at the, 201. , Disease of the, 191. -tip pain from liver ailments, 332. Sigaultean operation, 338. SiKmoid flexure, 313. Sinuses of skull, 80. Skull, 12. • — , Abnormalities of, 16. , Deformities of, 18. , Development of the, 14. , Fractures of, 17, 21, 22. , Necrosis of, 17. , Sutures of, 14. , Thickness of, 21. , Trephining the, 8. Socia parotidis, 92. Soft palate, 111. Solar plexus, 331. Soleus, 451. Spaces in the fasciae of the palm, 241,. of fontana, 51. Spasmodic stricture, 363. Spermatic artery, 370. cord, 370. plexus of veins, 370. Spina bifida, 340. Spinal accessory nerve, 122. cord. Concussion of, 508. , Contusion and crushing of, 509. , Length of the, 505. , Loss of motion due to injury of the, 513. , of sensation due to injury of the, 513. , Protection of the, 501. , Wounds of, 507. injuries and defiBcation, 514. and micturition, 514. and respiration, 513. and vomiting, 515. meninges, 506. meningitis, 507. nerves, Points of origin of, 512. Spine, 497. , Curves of, 497. — fractures and dislocations, 500. , Fractures of, 497. , Spi-ains of, 499. , Trephining the, 505. Spinous process of the vertebi-a promineus, 118. processes, Breaking the, 504. Sphincter ani, 346, 376. SplMy.foot, 485. Spleen, 322. , Capsule of the, 324. , Enlarged, 324. , Extirpation of the, 324. , Injuries to the, 322. , Relations of, 322. , Kupture of, 323. Stenson's duct, 91. Sbemo-clavicular joint, 172. , Disease of tlie, 174. , Dislocations of the, 175. , Movements of, 173. -mastoid. Congenital tu- mour of, 124. muscle, 120, 123. , Dividing the, 126. xiplioid joint, 148. Sternum, 148. , Fractures of, 148. , Holes in, 149. , Operations on the, 149. , Separation of segments of, 148. , Trephining the, 149. Stomach, 298. , FistulDB of, 301. , Foreign bodies in the, 302. , its proximity to the heart, 299. , its relation to the abdominal wall, 299. , Relations of, 298. , Vertical, 301. , Womids of the, 301. Strabismus, 36, 39. Stye, 56. Subarachnoid spice, 27, 507. Subastraijoloid diolocations of the foot, 482. Subclavian artery, 121. vein, 121. Subclavicular fossa, 164. Subclavius muscle, lfj7. Subconjunctival ha3iuorrhage, 56. Subdural space, 26, 27, 507. Sublingual bursa mucosa, 103. Subserous connective tissue of the abdomen, 271. Superior maxilla, 92. , Excision of the, 93. , Fractures of, 92. 1 1 530 Surgical Applied Anatomy. Superior maxilla, Necrosis of, 93. thyroid artery, 120. vena cava, 159. Supinator longus, 210, -^7. Supraclavicular artery, 121. nerves, 166. Supraorbital foramen, 86. Suprai-enal ai-tery, 265. Surgical emphysema, 156. Sustentaculum tali, 461. , Fracture of, 487. Sycosis, .56. Sylvian fissure, 29. Symbleph.aron, 57. Syme's amputation at the ankle, 490. Sympathetic opMlialmia, 49. Synecliise, 44. Synostosis of skull, 19. Synovial cavities of tbe foot, 489. — — sacs and sheaths in the hand, 247. Synovitis, Acute, in the hij) joint, 398. , , in the knee, 439. Sweat glands in the skin of the hand, 241. Tabatifere anatomique, 240. Tagliacozzi's operation, 204. Tahpes calcaneus, 484. cavus, 467. equinus, 483. and the plantar fascia, 467. , mixed or secondary forms, 485. valgus, 484. varus, 484. Tapping antrum, 81. Tarsal bones. Fractures and dis- locations of, 487. cartilage, 55. cyst, 56. Tarsus (see Foot). Taxis, Reducing an inguinal hernia by, 285, 288. Teale's operation for symble- pharon, 56. Temporal abscess, 8. fascia, 7. , Wound of simulating fracture, 8. fossa, 7. Temporomaxillary articulation, 96. , Dislocations at, 97. — , Fractures at, 96. sphenoidal lobe, 30. Tendo Ach'llis, 453, 403, 469. oculi, 58. Tenotomy and the peroneal nerve, 431. of hamstrings, 431. of sterno-mastoid, 126. Tensor palati. 111. Testicle, 368. Testis in the foetus, 282. , Investments of, 368. Thecal abscess, 248. 'J henar eminence, 237. Thickness of the skull cap, 24. Thigh, 417. , Amputation of the, 424. , Fasciae of, 419. , Fractures of, 421. , Integuments of, 418. , Muscles of, 419. , Surface anatomy of, 417. Thoracic duct, 334. viscera, 155. walls, 147. Thorax, 147. Thumb, Amputation of the, 253. , Dislocation of, 256. Thymus; 136. Thyroid body, 119, 138. , Division of isthmus of 138. in tracheotomy, 136. cartilage, 119, 132. Thyroidea ima artery, 136. Tibia and fibula fractures, 456. , Anterior border of the, 450. fractures, 447, 458. in rickets, 459. shaft, its strength, 456. Tibial arteries, 451, 471. Tibialis anticus muscle, 451. Tongue, 104. , Blood supply of, 106. , Epithelium of, 105. , Excision of, 108. , Mucous cysts of, 105. , Nerve supply of, 106. tie, 105. Tonsil, 115. , Bleeding from, 117. , Foreign body in, 117. , Hypertrophy of, 116. , , and deafness, 116. Tophi, 60. Trachea, 119, 131, 157. , Foreign bodies in, 137. Tracheotomy, 133, 136. tubes, 13 1. Transversalis fascia, 2S0, 315. Transverse arch of the foot, 480. Index. 53^ Transverse cervical artery, 121. colon, 310, 313. process di the atlas, 118. of cervical vertfbra, 118. Trapezium, 2tO. ridgre, 'I'Sl. Trephiniug, 8. Tiiangxilar ligament of the urethra, 341, 349. Trigone, 355, 357. Trismus, 100. Tubera ischii, 3:35, 381. Tubercle for the adductor magnus, 425. of the tibia, 425. Tubercular nail, 243. Tumours in th*! orbit, 34, 35. Tunica abdomiualis, 266. albusineu, 369. vaginalis, 282, 369. Tympanum, 67. Ulua, Dislocation of the, 220. , Fractm-es of the, 231, "S^\ Ulnar artery, 228. nerve, 204, 216. , Paralysis of the, 2 )0. , Strength of, 387. vein in venesection, 215. Umbilical hemia, 269, 289. Umbilicus, Fibrous ring of the, 268. , Position of the, 263. Urachus, 269. Ureter*, 3:30. and regui gitation of urine, 358. , Distension of, 330. -, Eupture of, 331. Urethi-a, Female, 365. , Male, 361 , , Curve of, 361. , Membranous, 363. , IVFucous membrane of, 364. , Narrowest parts of the, 364. , Penile, 364. — — , Prostatic, 363. , Rupture of ihe, 365. Urethral tr'angle, 344, 347. Uterus, Impregnated, 372. Vagina. 372. Vaginal cystocele, 372. Valsalva's method of inflating the mid'lle ear, 68. Valvular couniventes, 303. Varicocele, 371. Varicose veins, 454. Vas deferens, 370. Vastus intemus muscle, 417. Veins (see various parts). , Air in, 143, 185. Venesection in the foot, 472. on the arm, 214. Vermiform appendix, 312. Vertebral artery and articulation, 144. and neuralgia, 144. , Ligaturing the, 144. column, 497. Vesico-vaginal fistula, 359, 372. Vitello-intestinal duct, 308. Vitreous humour, 52. Volvulus of the sigmoid flexure, 313. Vulva, 372. Wardrop's operation in the neck, 143. Wax in ear, 62, 64. Weaver's bottom, 385. Wharton's duct, 102. White line at anus, 376. in tbe pelvic fascia, 341. Whitlow, 248. Wrist, 235. joint, 237, 251. , Amputations at, 257. , Dislocations at, 255. , Fractiu'es about, 252. , Movements at, 251. , Strength of the, 251. , Surface anatomy of the, 235 Wry- neck, 124. Zygoma, Fracture of, 9. CASSRLL AND COMPANY, BELLE SAUVAGE WORKS, LONDON, B.C. COLUMBIA UNIVERSITY LIBRARY This book is due on the date indicated below, or at the expiration of a definite period after the date of borrowing, as provided by the rules of the Library or by special ar- rangement with the Librarian in charge. DATE BORROWED DATE DUE DATE BORROWED DATE DUE AUI \ 2 2 1941 ! 1 i 1 ' C28(239)MI00 { QJ.:531 T7Z Treves Sur^^^ical applied anatomy •AMk^Ba^MMaaadhliksaika^aaamMMrfaMMMa^i^M^HaBiMM i I iBmui^jJIi* 'T»KH