protruding handlebar split his lower anterior muscles down to the peritoneum without damaging the skin or the peritoneumitself. So, in this case, andin Jamieson's, the anterior abdominal wall was suddenly forced against a sharp unyielding object. Normally the contracting abdominal musculature is a powerful guard to intra-abdominal structures and, though anterior wall bruises are common, traumatic hernia is rare.
When examining the abdomen of a patient brought in from a road accident, special note should be made of the site of bruises as they may help to some extent to localize intraperitoneal injury.
Motor Cyclists.-A motor cyclist crouches over his machine, bending his hips and knees, and brings his upper pelvis to the lower thoracic cage so as to decrease the area of the abdominal wall. The anterior wall also lies on the comparatively smooth-surfaced petrol tank.
As is known, motor cyclists usually damage the thigh, leg, or ankle besides the other less common injuries.
Car Occupants.-With the safety harness across the chest and anterior abdominal wall, on impact, the supported car occupant is not thrown about.
Those car occupants without safety harnesses sit with the hips flexed and again the abdominal wall to some extent is protected.
Motor cyclists, pedestrians, and car occupants are often thrown considerable distances on impact. It is surprising that they do not more often injure the anterior abdominal wall from falling on to a sharp I54