Pneumomediastinum after injection injury to the hand.

Pneumomediastinum as a consequence of injection injury to the hand has not been previously reported. We present a 22-year-old male who developed pneumomediastinum when a high pressure hose injected air into his hand. The anatomic continuity between peripheral ulnar neurovascular bundle and the hilar vessels provided the route for air entering the hypothenar eminence to penetrate the mediastinum. After ruling out life-threatening causes of pneumomediastinum such as esophageal perforation, his management included observation and serial radiographs. By one week there was complete resolution of the mediastinal air. This report demonstrates that pneumomediastinum may be associated with air injection injury of the hand, and that expectant management is appropriate.