Evaluation of nerve transfer techniques for shoulder function recovery in traumatic brachial plexus injuries: A...

Traumatic brachial plexus injuries can significantly impair shoulder function, particularly abduction and external rotation. Various nerve transfer techniques are available to restore these functions. This meta-analysis evaluates the efficacy of different nerve transfers for shoulder abduction and external rotation recovery to identify the most effective surgical approaches.

A literature search was conducted in PubMed and Mendeley up to June 2025 following PRISMA guidelines. Studies were included if they involved nerve transfers to the suprascapular and/or axillary nerves in patients with traumatic brachial plexus injuries. Studies were excluded if they were not in English, involved patients under 16 years old, reported direct axillary or suprascapular nerve injuries, or presented aggregated data. Outcome measures included abduction and external rotation strength and range of motion (ROM), assessed using the Medical Research Council (MRC) scale and angle measurements. Statistical analyses included chi-squared tests, Kruskal-Wallis tests, Dunn-Bonferroni post-hoc tests, and logistic regression.

A total of 29 studies involving 393 patients were included. Among nerve transfers, the spinal accessory to suprascapular combined with long head of triceps to axillary (SAN-SSN + LHT-AxN) transfer showed the highest rates of satisfactory abduction and external rotation and the highest mean ROM values. Double transfers consistently outperformed single transfers, particularly regarding satisfactory abduction outcomes and ROM. Older age and prolonged denervation time were associated with poorer outcomes, whereas partial plexus injuries showed better recovery compared to total plexus injuries.

Double nerve transfers targeting the suprascapular and axillary nerves, especially the SAN-SSN + LHT-AxN technique, demonstrate superior shoulder function recovery. Early intervention is crucial for optimizing outcomes, and the choice of technique should be tailored to injury severity and patient-specific characteristics.