gms | German Medical Science

Objectives/Interrogation: We report the patterns of infraclavicular brachial plexus injuries (BPI) after anterior shoulder dislocation and their functional recovery rates.

Methods: This was a retrospective review of a prospectively-maintained database of patients who presented with infraclavicular BPI following anterior shoulder dislocation. Each patient was examined by the senior author. All underwent EMG and MRI of the affected shoulder. Patients were followed up until functional recovery was achieved.

Results and Conclusions: Between 2014-18, 42 patients (23 male:19 female) with a mean age of 61 years (range 15-87) presented with these injuries. There were 15 pure shoulder dislocations and 27 fracture-dislocations. Twelve had concomitant rotator cuff tears. Four patterns of nerve injuries were observed: a) Isolated axillary nerve (n=20), b) 3-cord plexopathy (5), c) 2-cord injury (axillary & medial - 2, medial & posterior - 4, posterior & lateral - 1), d) Single cord injury (medial - 6, posterior - 3, lateral - 1).

The mean follow-up duration was 15 months (SD 11). Overall, 45% had full spontaneous recovery, 29% had partial recovery and 26% had no recovery at the time of their latest review. All lateral cord palsies recovered spontaneously to M4/5 elbow flexion (either in isolation or in combination with other cords). Amongst 13 posterior cord palsies, 11 recovered to M4/5 elbow extension and 2 did not show recovery at the 7-month review. Of the 17 medial cord palsies, 6 patients regained M4/5 intrinsic power, 5 recovered to grade M1-3, and 6 did not show any recovery at a mean of 13 months post injury. For those with isolated axillary nerve palsy, 11 recovered to M4/5 deltoid power, one had M3 activity, one did not show recovery at 7-months, and 7 underwent radial-to-axillary nerve transfer at a mean duration of 9 months post injury.

Nerve injury following anterior shoulder dislocation is not necessarily a benign condition. Isolated axillary nerve palsy is the commonest associated nerve injury with 60% spontaneous recovery rate. Lateral and posterior cord injuries have the best spontaneous recovery potential. The presence of medial cord palsy signifies a more severe nerve injury and recovery of hand function is often poor. All nerve palsies should be monitored closely and early referral to a specialist nerve service is recommended.