Anterior interosseous nerve avulsion.

A 19-year-old man with a fracture of the distal humerus avulsed the anterior interosseous nerve. Avulsion of this nerve may be more common than previously believed. As shown by a cadaver study, the mechanism of injury is related to traction on the median nerve. Complete clinical assessment requires an accurate neurological examination; specifically, the integrity of the anterior interosseous nerve is tested, and a characteristic disturbance of pinch is identified. By treatment with a free nerve graft it is possible to achieve full functional recovery.