Axillary nerve injury: diagnosis and treatment.

Axillary nerve injury is infrequently diagnosed but is not a rare occurrence. Injury to the nerve may result from a traction force or blunt trauma applied to the shoulder. The most common zone of injury is just proximal to the quadrilateral space. Atraumatic causes of neuropathy include brachial neuritis and quadrilateral space syndrome. The vast majority of patients recover with non-operative treatment. Baseline electromyographic and nerve conduction studies should be obtained within 4 weeks after injury, with a follow-up evaluation at 12 weeks. If no clinical or electromyographic improvement is noted, surgery may be appropriate. The results of operative repair are best if surgery is performed within 3 to 6 months from the injury. Surgical options include neurolysis, nerve grafting, and neurotization. The results of repair of axillary nerve injuries have been good compared with treatment of other peripheral nerve lesions, due to the monofascicular composition of the nerve and the relatively short distance between the zone of injury and the motor end-plate.