Arthroscopic subscapularis-complex release and conjoint tendon transfer in birth brachial plexus injuries: a case series with evidence-based insights.

PURPOSE: Shoulder deformities and impaired function in individuals with birth brachial plexus injury (BBPI) are often caused by internal rotator (IR) contractures and abductor weakness, which may progress to glenohumeral dysplasia. Although subscapularis-complex release and tendon transfer is a time-tested procedure, there are controversies regarding the appropriate management of shoulder contractures, especially in preschool children. Therefore, this study examines the efficiency of arthroscopically done progressive controlled release of IR contracture combined with tendon transfer.

METHODS

This study included 12 children who presented with shoulder soft tissue contractures and functional impairments, specifically, loss of shoulder abduction and external rotation, but with good deltoid function. They underwent a surgical intervention involving arthroscopy-assisted subscapularis-complex release and conjoint muscle transfer onto the infraspinatus footprint on the humeral head. The evaluation of shoulder function was conducted using the Mallet score system, and the range of motion was measured at preoperative and six month postoperative intervals. Statistical analyses were performed to determine the significance of the outcomes.

RESULTS

The average age of participants was 4.83 ± 2.1 years. Preoperatively, the mean Mallet score was 14.08 ± 1.4, which improved to 23.83 ± 1.2 postoperatively. The average gain in shoulder abduction was 66.4 ± 5.6°, and external rotation improved by 85.4 ± 16.6° at 18 months final follow-up. All patients exhibited improvements in shoulder function, with a significant correlation (p value = 0.037) between Naraka grading, and clinical outcomes.

CONCLUSION

The combined surgical approach of arthroscopic subscapularis-complex release with conjoint tendon transfer effectively enhances the shoulder function in the studied cohort. Further research and extended follow-up are needed to evaluate the long-term benefits.

LEVEL OF EVIDENCE: Level IV (Therapeutic case series).