Tendon Transfers to Restore Shoulder Function for Obstetrical Brachial Plexus Palsy

Abstract

Background: Obstetrical brachial plexus palsy (OBPP) is a relatively common stretch injury of the brachial plexus sustained during delivery. Tendon transfers are commonly performed to improve shoulder function among patients with OBPP. Although several techniques for the surgical management of OBPP exist, it is unclear whether tendon transfers to the rotator cuff vs. posterior humerus yield different outcomes. Methods: A systematic search in PubMed, Web of Science, the Cumulative Index to Nursing and Allied Health Literature, the Cochrane Library, and Google Scholar up to January 1, 2021, was performed. Relevant publications were classified by surgical technique of tendon transfers to the rotator cuff or posterior humerus. The standard mean difference (SMD) and 95% confidence intervals were calculated to compare preoperative and postoperative aggregate Mallet scores as well as abduction and external rotation scores using the Mallet scale. A p value of <0.01 was considered significant. Results: Data from 26 studies and 951 patients (46.2% male patients) with a mean age of 68.9 ± 29.3 months were included. Eight hundred three patients underwent tendon transfer to the rotator cuff and 148 to the posterior humerus. The average postoperative follow-up period was 45.2 ± 21.7 months. The pooled cohort had an overall improvement in postoperative aggregate Mallet scores (SMD = 5.53, p < 0.001), abduction scores (SMD = 1.79, p < 0.001), and external rotation scores (SMD = 1.99, p < 0.001). Tendon transfer to the rotator cuff had a greater postoperative improvement in abduction (SMD = 1.90, p < 0.001) than transfer to the posterior humerus (SMD = 1.32, p < 0.001) while both techniques yielded similar improvements in external rotation (rotator cuff SMD = 2.01, p < 0.001, posterior humerus SMD = 1.98, p < 0.001). Conclusion: This is the first systematic review comparing outcomes for tendon transfers to the rotator cuff vs. the posterior humerus for improving shoulder function in patients with OBPP. Overall, tendon transfers are an effective treatment for improving shoulder function. Transfer of the latissimus dorsi and teres major to the rotator cuff compared with transfer to the posterior humerus results in greater improvement in abduction while both techniques have similar results in improving external rotation. Level of Evidence: Level I Systematic review of Level I and Level II studies