Acute traumatic aortic injury with intimal flap at the aortic isthmus and periaortic hematoma without active bleeding seen. Incomplete right rib fractures anterolaterally.

This case emphasizes the insensitivity of chest radiographs in identifying aortic injuries, particularly in supine elderly patients where superior mediastinal widening is a common normal finding. Instead of looking for widening (which is almost always present), looking for asymmetric widening of tissue to the left of the trachea compared to the right should alert you to the possibility of an aortic injury.