Peripheral nerve injury associated with shoulder trauma: a retrospective study and review of the literature.

PURPOSE: To determine the incidence of peripheral nerve injury in patients referred to an electrodiagnostic laboratory with a history of shoulder trauma. The characteristics of those presenting with the triad of shoulder dislocation, peripheral nerve injury, and rotator cuff tear were further examined.
METHODS: We conducted a retrospective chart review of all patients referred to our electrodiagnostic laboratory over a 17-month period. Requisitions, clinical histories, physical findings, electrophysiological results, and radiologic investigations were reviewed. Inclusion for analysis was a clinical history of shoulder trauma and electrophysiological evidence of nerve injury.
RESULTS: Of 1844 patients studied, 48 had nerve injury associated with trauma to the shoulder. Twenty presented with brachial plexopathies; 17 isolated mononeuropathies (axillary nerve was most common, 47%); and 11 multiple nerve involvement. Of the multiple nerves involved, the axillary was most commonly affected (45% axillary and musculocutaneous; 36% axillary and suprascapular). Fifteen (31%) patients had a history of shoulder dislocation, whereas 5 (10.4%) demonstrated the triad of dislocation, nerve injury, and rotator cuff tear.
CONCLUSIONS: Peripheral nerve injury is an important consideration in patients with shoulder trauma. For patients presenting with nerve injury post-shoulder dislocation, it is important to consider a potential concomitant rotator cuff tear as an ongoing source of pain or weakness. Similarly, a patient with a rotator cuff tear following dislocation may have an associated peripheral nerve lesion.