Change in shoulder external rotation strength and motion after lower trapezius transfer to the infraspinatus in children with obstetric brachial plexus palsy

Lower Trapezius Tendon Transfer for Restoration of External Rotation in Brachial Plexus Birth Injury

OBJECTIVE

Patients with brachial plexus birth injuries (BPBIs) are at risk for limitations in shoulder external rotation. The role of lower trapezius tendon transfer to restore shoulder external rotation in this population has not been well characterized. This study aimed to evaluate the utility of lower trapezius tendon transfer for restoration of external rotation in a subset of pediatric patients.

METHODS

Seventeen pediatric patients with BPBI were treated with lower trapezius tendon transfer to restore external rotation of the shoulder. Mean age at surgery was 8 years, and 11 were female. Six patients had prior shoulder surgery to restore external rotation, while 1 had prior nerve surgery to restore shoulder function. Range of motion before lower trapezius transfer and at latest follow-up was obtained. Mean follow-up was 36 months.

RESULTS

Active forward flexion did not significantly change from preoperative to final follow-up (mean, 147° and 141°; P = 0.46). External rotation in adduction significantly changed from preoperative to final follow-up (mean, 4° and 26°; P < 0.001). External rotation in abduction significantly changed from preoperative to final follow-up (mean, 75° and 84°; P = 0.048). Six patients (35%) had subsequent surgeries at average 17 months from this procedure. Significant univariate associations with subsequent surgery included certain intraoperative concomitant procedures-coracoid osteotomy/excision (P = 0.02) and biceps tenodesis (P = 0.04)-while bony glenoid augmentation/reconstruction trended toward significant association (P = 0.05).

CONCLUSIONS

Lower trapezius tendon transfer for BPBI showed a statistically significant but unlikely clinically meaningful improvement in external rotation with a high rate of reoperation.