The initial chest radiographs of 54 trauma patients who were referred for angiography of the thoracic aorta were reviewed. Retrospective evaluation used eight radiographic signs that have been described in possible aortic injury. This review was undertaken to establish the occurrence and validity of these signs in the diagnosis of aortic tear. Results indicated that loss of the aortic arch contour and mediastinal widening were the most reliable signs of disruption of the aorta. In patients with at least one of these two signs, there was a high percentage of positive angiograms.