The effect of derotational humeral osteotomy on global shoulder function in brachial plexus birth palsy.

BACKGROUND: Derotational humeral osteotomies have been used in older children with brachial plexus birth palsy and glenohumeral joint deformity to place the upper extremity in a more functional position. The purpose of this study was to determine the effects of these procedures on shoulder function and joint morphology.

METHODS: Forty-three patients underwent a derotational humeral osteotomy for functional impairment in the setting of internal rotation contracture and/or glenohumeral joint deformity at our institution from 1996 to 2004. Osteotomies were performed proximal to the deltoid insertion and were stabilized with plate-and-screw fixation. The average age of the patients at the time of surgery was 7.6 years (range, 2.3 to 17.0 years). Shoulder function was graded according to the modified Mallet classification system. Glenohumeral deformity was graded according to the classification scheme of Waters et al. The results for twenty-seven patients who were followed for a minimum of two years (average, 3.7 years) are reported.

RESULTS: The average amount of external rotation achieved with osteotomy was 64 degrees (range, 35 degrees to 90 degrees). The mean aggregate Mallet classification score improved from 13 to 18 points (p < 0.01). The mean Mallet classification scores for the individual elements similarly demonstrated improvement following osteotomy, with the greatest gains in hand-to-mouth, hand-to-neck, and external rotation motions. The mean classification of the glenohumeral deformity was type IV preoperatively and postoperatively, signifying the persistence of glenohumeral dysplasia. There were no nonunions. One patient required a revision osteotomy for inadequate initial correction. One patient sustained a humeral fracture distal to the plate fixation because of sports-related trauma.

CONCLUSIONS: Derotational humeral osteotomy improves shoulder function in patients with brachial plexus birth palsy, internal rotation contracture, and/or advanced glenohumeral joint deformity. This osteotomy provides an attractive treatment option for patients with brachial plexus birth palsy who have advanced glenohumeral dysplasia precluding soft-tissue releases and tendon transfers.