Axillary nerve neurotization by a triceps motor branch: comparison between axillary and posterior arm approaches.

Objectives: This study is aimed at comparing the functional outcome of axillary nerve neurotization by a triceps motor branch through the axillary approach and posterior arm approach.

Methods: The study included 27 patients with post-traumatic brachial plexus injury treated with axillary nerve neurotization by a triceps motor branch for functional recovery of shoulder abduction and external rotation. The patients were retrospectively evaluated and two groups were identified, one with 13 patients undergoing axillary nerve neurotization by an axillary approach and the second with 14 patients using the posterior arm approach. Patients underwent assessment of muscle strength using the scale recommended by the British Medical Research Council, preoperatively and 18 months postoperatively, with useful function recovery considered as grade M3 or greater.

Results: In the axillary approach group, 76.9% of patients achieved useful abduction function recovery and 69.2% achieved useful external rotation function recovery. In the group with posterior arm approach, 71.4% of patients achieved useful abduction function recovery and 50% achieved useful external rotation function recovery. The difference between the two groups was not statistically significant ( = 1.000 for the British Medical Research Council abduction scale and  = 0.440 for external rotation).

Conclusion: According to the British Medical Research Council grading, axillary nerve neurotization with a triceps motor branch using axillary approach or posterior arm approach shows no statistical differences.