Arthroscopic isolated capsular release for shoulder contracture after brachial plexus birth palsy: clinical outcomes in a prospective cohort of 28 children with 2 years' follow-up

Background The primary objective of this study was to evaluate improvements in external rotation after isolated arthroscopic capsular release in children with shoulder contracture due to brachial plexus birth palsy. Materials and methods This study included all children older than 2 years with a range of active external rotation limited to 30° or less and/or active anterior elevation (AE) limited to 90° or less secondary to brachial plexus palsy treated between 2011 and 2015. Passive glenohumeral motion, passive global (glenohumeral plus scapulothoracic) motion, active global motion for external rotation with the elbow at the side (ER1), AE, and internal rotation with the elbow at the side were recorded before and 2 years after surgery. Improvement was evaluated by comparing the preoperative and follow-up values. The operation performed was subscapularis-sparing arthroscopic capsular release. Results Thirty-five patients were included, and 28 completed 2 years of follow-up. The average changes in active global ER1, passive glenohumeral ER1, and passive global ER1 were +35° (range, −20° to +100°; P  .0001), +35° (range, +0° to +75°; P  .0001), and +26° (range, −15° to +60°; P  .0001), respectively. There were no significant changes in internal rotation with the elbow at the side or AE. The mean improvement in the aggregate Mallet score was 3.9 points (range, −3 to +9 points; P  .0001). Conclusions For children with shoulder contracture secondary to brachial plexus palsy, subscapularis-sparing isolated capsular release improves external rotation and functional scores and avoids any loss of active internal rotation but does not improve AE.