CHEST 265 ing force is applied, and near the angles at the back, the force travelling along the ribs. These are not always accompanied by external injuries or ecchymoses of blood in the soft tissues over the ribs, Sternum.—Fracture of the sternum is rare. It is ordinarily due to direct violence, and usually occurs transversely either between the manubrium and gladiolus or a little below this level. The fragments remain in apposition or the upper portion passes backwards behind the lower, and is liable to damage the viscera behind it. The sternum may be fractured by indirect violence as the result of forcible flexion or extension of the body. In such cases it is possible for a vertebral bone to be fractured. The sternum may rarely be fractured spontaneously by muscular spasm caused during violent coughing. Bass and Small13 report a case in which a 51-year-old man, who was suffering from pulmonary tuberculosis, sustained a sudden and spontaneous fracture of the sternum during a pronounced cough. There was no history of trauma nor was there any evidence of intrinsic bone disease. Lungs.—Wounds of the lungs may be immediately fatal from profuse haemorrhage, or from suffocation due to respiratory embarrassment on account of the presence of blood in the pleural cavity or in the air-passages, or may result in death subsequently from septic pneumonia. They may be produced by penetrating wounds of the chest caused by a cutting or stab- bing instrument, by the sharp fragments of a fractured rib, or by a projectile from a firearm. The haemorrhage is recognized by the escape of bright red and frothy blood from the mouth, and from an external wound, ' if present. Contusions or lacerations of the lungs may be produced by blows from a blunt weapon or by compression of the chest even without fracturing the ribs or showing marks of external injury. These may cause instantaneous death or may result in pleurisy, traumatic pneumonia or hsemothorax. In June 1919, a girl, 3 years old, was run over by an rkfca and died immediately. At the autopsy there was no external mark of injury to the chest nor were the ribs fractured, but the left lung was found lacerated. In February 1922, a Mahomedan girl, 15 years old, received a kick on the chest from her husband, and died within an hour. On examination no external injury was visible, but there was a laceration of the lower lobe of the left lung which was fibroid from disease. The body of a Hindu female was found lying near the railway line near Alambagh on or about the llth November 1925. Post-mortem examination showed a bruise, 3" X 1", obliquely across the left side of the chest 3" below the left collar bone, but no fracture of any ribs. The right lung was lacerated in front 1" below the apex and a contusion, 2" X 2", was found on the base of the left lung. These appeared to have been caused by compression of the chest. A Hindu male, 25 to 30 years old, was crushed under a machinery in a workshop on January 3, 1929, and died on the next day. Post-mortem examination did not show any marks of external violence on the chest or fracture of the ribs. The chest cavity contained blood, and the right lung had four contusions on its anterior aspect, while the left lung showed a contusion of its root and a tear, 2£" long, over its lower lobe. There was also dislocation of the fourth cervical vertebra. A boy,14 8 years old, was knocked down by a heavy cart and was supposed to have been run over, but there was not the slightest trace of abrasion or bruising of the chest, not behind the ribs and sternum. The upper lobe of the right lung, however, had been completely cut off from its root, and it floated freely in a pleura filled with blood. Heart.—Wounds of the heart are produced by a cutting or stabbing instrument, a bullet or a sharp end of a fractured rib or sternum. wounds are commonly instantly fatal from shock and haemorrhage ex -------------------,----------------------------------,--------- ' i 13. Jour. Amer. Med. Assoc., Sep. 20, 1952, Vol. 150, p. 209. 14. J. B. Cleland, Med. Jour. Austral, Sep. 9, 1944, Vol. 31, p. 278.