Arthroscopic treatment of posterior glenohumeral joint subluxation resulting from brachial plexus birth palsy.

The purpose of this study is to assess the ability of arthroscopic anterior capsular release, subscapularis tenotomy, and glenohumeral manipulation to reduce glenohumeral joint subluxation resulting from brachial plexus birth palsy. Twenty-two children with a mean age of 3.9 years (range, 1.6-8.3 years) underwent preoperative magnetic resonance imaging, arthroscopic surgery with or without tendon transfers, and postoperative imaging in their spica cast. In the uninvolved shoulders, the mean percentage of the humeral head anterior to the middle of the glenoid fossa (PHHA) was 45.2% +/- 4.8% and the mean glenoid version was -7% +/- 3%. In the involved shoulders, preoperatively, the mean PHHA was 15.6% +/- 13.5% and the mean glenoid version was -37 degrees +/- 15 degrees . Postoperatively, the mean PHHA corrected to 46.9% +/- 11.2% and the mean glenoid version improved to -8 degrees +/- 8 degrees . There was a significant improvement in the mean PHHA (P < .001) and mean glenoid version (P < .001) that approached the values of the uninvolved shoulder. Arthroscopic capsular release and subscapularis tenotomy were successful in obtaining reduction of glenohumeral joint subluxation in all patients. The maintenance of reduction requires continued follow-up over time.