Ulnar nerve palsy associated with fracture of the distal radius.

OBJECTIVE

To describe the clinical features and outcome of a series of patients with complete motor and sensory ulnar nerve palsy associated with a fracture of the distal radius.

DESIGN

Retrospective case series.

SETTING

Level 1 trauma center.

PATIENTS/

PARTICIPANTS

Five adults with acute complete motor and sensory ulnar nerve palsy associated with fracture of the distal radius were treated during a 2 year period. There were 3 men and 2 women, with an average age of 42 years (range, 33 to 56 years). All 5 distal radius fractures were high energy and widely displaced. Three patients had an associated ulna fracture (2 styloid, 1 styloid and distal diaphysis), and 1 had a complete triangular fibrocartilage complex (TFCC) avulsion from the distal ulna (associated with an open wound). Two patients had open fractures.

INTERVENTION: Open reduction and internal fixation of the distal radius fracture in 4 patients and external fixation in 1 patient. Three patients had exploration and release of the ulnar nerve because it was associated with an acute carpal tunnel syndrome.

MAIN OUTCOME MEASUREMENTS: Recovery of ulnar nerve function.

RESULTS

At an average follow-up of 17 months, 4 patients had complete or near-complete recovery of ulnar nerve function. One patient had moderate motor and mild sensory dysfunction.

CONCLUSIONS

Acute ulnar nerve palsy may occur in association with high-energy, widely displaced fractures of the distal radius. These are usually neurapraxic injuries that recover to normal or near-normal strength and sensation. We recommend exploration and release of a complete ulnar nerve palsy associated with a fracture of the distal radius fracture when there is an open wound or an acute carpal tunnel syndrome, and observation without exploration otherwise.