Seat belt aorta: acute dissection and thrombosis of the abdominal aorta.

Aortic trauma mainly involves the thoracic aorta (95%), while the abdominal aorta is infrequently involved (5%). Of growing interest is the role of seat belts in abdominal aortic injuries. Although seat belts are known to cause injuries to the abdominal viscera, they rarely produce aortic trauma. We report here an acute dissection with thrombosis of the abdominal aorta leading to complete peripheral occlusion as a result of lap-type seat belt injury. The two previously reported cases of similar injuries which resulted in incomplete occlusion are reviewed. A hypothesis for the causal mechanism of these injuries is described. The authors also stress careful follow-up of all patients with seat belt injuries since other intra-abdominal vascular injuries may be present.