61. ARTHROSCOPIC TREATMENT OF EXTERNAL ROTATION OF THE SHOULDER FOR SEQUELAR OBSTETRICAL BRACHIAL PLEXUS INJURIES: 13 CASES

Abstract

Purpose of the study: A stiff shoulder in internal rotation is a classical complication of obstetrical injury to the brachial plexus. The condition generally associates glenohumeral dysplasia. In 2003, Pearl proposed arthroscopic release of the shoulder, with or without latissimus dorsi transfer as an alternative to an open procedure. We report a series of 13 patients who underwent this procedure.

Material and method: From 2004 to 2007, 13 children aged 1 to 11 years (range 3.5) underwent surgery. The procedure was an arthroscopic tenotomy of the intra-articular portion of the subscapularis associated with release of the anterior capsuloligament structures without tendon transfer. A thoracobrachial resin cast maintained the shoulder in maximal external rotation for six weeks. The functional outcome was assessed on the basis of the passive and active range of motion and the Mallet score. Pre and postoperative MRI was used to assess glenohumeral dysplasia and check its correction.

Results: Mean follow-up was 23 months (range 5–40). There were no complications. Mean immediate postoperative gain was 53 (range 30–70) for external rotation (RE1). On average, passive RE1 improved from −5.4 to +57.7. Eight patients (61%) recovered active external rotation (57.5 on average). Mean active abduction improved from 45.8 to 56.5. Active internal rotation declined in 38% of the shoulders. The Mallet score improved in 69% of the shoulders. The best results were observed for children aged less than 4 years. There was one failure, related to major dyplasia which could not be reduced with an open procedure. Correction of the glenohumeral dysplasia was noted on 7 of the 9 MRI performed and the retroversion angle of the glenoid improved from −28.2 to −25.6, on average.

Discussion: Open techniques are aggressive and only variably effective. A majority of our patients (8/13) achieved improved passive and active RE1 solely with the arthroscopic procedure. Correction of the glenohumeral dysplasia with growth appears to correspond to the clinical improvement but further follow-up is needed.

Conclusion: Our results are comparable with those reported by Pearl. This is a minimally invasive easy-to-perform technique. For children aged less than 4 years, systematic tendon transfer does not appear to be necessary.