Blunt thoracic aortic injury (BAI) is a rare but often fatal injury that occurs with severe polytrauma. Immediate diagnosis and treatment of BAI are essential for a successful outcome. We reviewed our experience with 20 patients with BAI treated at a Level I trauma center between 1995 and 2006. The mean Injury Severity Score was 38 +/- 14 and 14 patients had an abnormal Glasgow Coma Score; associated injuries included abdomen in 13 patients, extremity in 12, and head in six. Chest x-ray (CXR) findings were suggestive of aortic injury in 15 patients, equivocal in three, and showed no evidence of aortic injury in two. Diagnosis was made by CT angiography (CTA) in 17 patients, transesophageal echocardiography (TEE) in two, and formal angiography in one. Sixteen patients underwent operative repair of BAI. Of these, eight also underwent laparotomy, six had operative repair of extremity fractures, and three had pelvic embolization. Five patients died, three of whom were treated nonoperatively, and length of hospitalization in survivors was 32 +/- 20 days. BAI is rare and often associated with multiple life-threatening injuries complicating diagnosis and treatment. Our data support the aggressive use of CTA even when classic CXR findings are not present. When CT must be delayed for abdominal exploration, intraoperative TEE is useful.