The seromuscular tear and other intestinal lesions in the seatbelt syndrome: a clinical and pathologic study of 29 cases.

The authors describe the clinical and pathologic findings in 29 patients with injuries from motor vehicle accidents. The seromuscular tear (SMT), the hallmark intestinal injury of the seatbelt syndrome, is an unambiguous lesion similar in all segments of bowel and is caused by a tear that separates the inner muscularis from the submucosa. It is characterized by (1) a wedge that strips the submucosa from the inner circular muscle; (2) a bending retraction of the torn muscularis toward the uninvolved bowel wall; (3) mucosal-submucosal fold effacement, causing the mucosa-submucosa bridge spanning the tear to become paper thin; and (4) the vulnerability of this bridge to ischemia that in 35% of the tears studied culminated in incipient or frank perforations and/or gangrene.