Derotational Pronation-producing Osteotomy of the Radius and Biceps Tendon Rerouting for Supination Contractures in Neonatal Brachial Plexus Palsy Patients: A Review of 20 Cases.

BACKGROUND: Forearm supination contractures can occur as a result of neurological derangement of the upper extremity in patients with neonatal brachial plexus birth palsy. The contractures become problematic in childhood as patients begin requiring forearm pronation for activities of daily living including typing on a keyboard and writing. There have been several techniques described to remedy this deformity. We present a case series describing the early clinical results of combined radial osteotomy and intraosseous biceps rerouting to realign the forearm in resting pronation and convert the biceps from a supinator to a pronator.

METHODS: A retrospective review identified patients who had a radial osteotomy and biceps rerouting for supination contracture between 2006 and 2016. Inclusion criteria required a fixed forearm supination contracture, patients below 18 years of age and at least 1 year of clinical and radiographic follow-up. Demographic and surgical variables, early clinical results, complications, reoperations, and revisions were documented.

RESULTS: Twenty patients were identified who met inclusion criteria. The mean follow-up was 3 years (range, 1 to 9 y). We observed a statistically significant difference in the mean resting position of the forearm from 56 degrees of supination preoperatively to 17 degrees of pronation postoperatively. Correspondingly, there was an increase in passive forearm pronation from 0 degree preoperatively to 66 degrees postoperatively and an expected decrease in passive forearm supination from 78 degrees preoperatively to 41 degrees postoperatively. There were 2 complications which were both radial osteotomy nonunions. Excluding revisions, there were 14 reoperations in 14 patients (63%) for hardware removal. Hardware removal was considered an expected return to the operating room, not an unplanned reoperation. There were 2 revisions for osteotomy nonunion, both of which went on to eventual union. Overall survivorship from the need for revision surgery was 95% at 12 months, 88% at 24 months, and 88% at 60 months. There were no recurrences of the supination contracture.

CONCLUSIONS: We present results of a novel surgical solution to forearm supination contractures through the combination of a derotational osteotomy of the radius and biceps tendon rerouting. The results show a significant benefit in forearm positioning and passive pronation with excellent survivorship and maintenance of correction.

LEVEL OF EVIDENCE: Level IV-therapeutic.