Missed proximal radioulnar joint translocation with ulnar nerve entrapment: an unusual injury in a child.

Traumatic elbow dislocation in a child is rare, and it is usually associated with fractures. Simultaneous proximal radioulnar joint (PRUJ) translocation with ulnar nerve palsy is even rarer. We report an unusual case of a missed PRUJ translocation with ulnar nerve entrapment in a 10-year-old child. The key to diagnosing the translocation is the position of the proximal radius, which lies medial to the ulna. This was treated by open reduction and release of the entrapped nerve. The ulnar nerve palsy recovered fully at the 1-year follow-up. Although PRUJ translocation with ulnar nerve entrapment is a rare injury, a successful outcome is possible with timely open reduction and release of the ulnar nerve.