Musculocutaneous nerve entrapment revisited.

Compression of the lateral cutaneous nerve of the forearm (LCNF), the distal sensory termination of the musculocutaneous nerve, can occur below the biceps aponeurosis, most commonly after strenuous elbow extension or forearm pronation. Between 1965 and 1992, 15 patients reported pain in the anterolateral elbow with "burning" into the forearm. There was a minimum 2-year follow-up of all patients in the study (average 13.4 years, median 15 years). All patients were managed conservatively for 12 weeks. Of the 15 patients, 11 required operative decompression that involved resecting a triangular wedge of aponeurosis overlying the nerve. Of the four nonoperative patients, one had persistent hypesthesia even though pain was relieved and range of motion was restored. Of the 11 patients treated operatively, none had recurrence of hypesthesia, and all patients continued to have complete relief of pain and full range of motion. One additional patient required surgery for lateral epicondylitis 2 years later. There were no operative complications.