Surgical Restoration of Pediatric Forearm Supination Deformity in Obstetric Brachial Plexus Palsy

Abstract

Purpose: Obstetrical palsy of the upper extremity repre-sents a severe traumatic complication, which involves thebrachial plexus and occasionally the osteoarticular struc-tures and muscles of the shoulder. Our aim is to describeand find an adequate modality of treatment for the rela-tively frequent obstetrical palsy sequela presented as fore-arm supination deformity. Forearm supination deformitytends to be progressive and therefore early recognition ofthis deformity is of paramount importance to prevent fixeddeformities, which increase the hand function deficit.Forearm supination deformity is classified in two stages:flexible (posture in supination) and fixed (contracture)deformity, which directly determine the choice of the oper-ative procedure(s). When passive reduction of the supina-tion deformity is possible (flexible deformity) soft tissueprocedures including tendon transfers are indicated. Thebony procedures should be preferred in cases with severecontracture of the forearm in supination and distal radio-ulnar joint luxation (fixed deformity). In this study we usedsoft tissue techniques (including biceps re-routingpronotoplasty, brachioradialis re-routing pronotoplastywith or without interosseous membrane release) and tech-niques which include osteotomy of the forearm bones (ex-cision of the radial head, radius pronation osteotomy, distalradio-ulnar fusion and wrist arthrodesis) to restore fore-arm posture and wrist stability in patients with supinationdeformity secondary to brachial plexus birth palsy.Methods: Forty-three children (27 male, 16 female) whoseage ranged between 3 and 15 years (mean age 8.2) oper-ated between 1998 and 2004 were included in this study.Eighteen of them (11 male, 7 female) underwent soft tissueprocedures, while twenty-five (16 male, 9 female) hadosteotomy.Results: As soft tissue procedures, the selected tech-niques were biceps re-routing pronotoplasty for 4 children and brachioradialis re-routing pronotoplasty for 14 ofthem. Average gain in active pronation was 82.5 degrees,average loss of active supination was 22.5 degrees andaverage gain in total active motion was 55 degrees forthe biceps re-routing group, whereas average gain inactive pronation was 63.5 degrees, average loss of activesupination was 11 degrees and average gain in total activemotion was 53.2 degrees in brachioradialis re-routinggroup. Selected techniques were excision of the radialhead for 4 patients, radius pronation osteotomy for 6patients, distal radio-ulnar fusion for 4 patients and wristarthrodesis for 4 patients as the osteotomy procedures.Average gain in active pronation was 96 degrees in radiushead excision, 66 degrees in radius pronation osteotomy,61 degrees in distal radio-ulnar fusion and 58 degrees inwrist arthrodesis groups. For the osteotomy group as awhole, the mean active forearm supination decreasedfrom 50.4 degrees preoperatively to 40.8 degrees after sur-gery. More than one procedure (mostly 2-3) were oftennecessary to achive the desired results.Conclusions: These results clearly show that patients canbenefit from surgical correction of forearm supinationdeformity which probably will cause significant improve-ment in functional status. After these surgical procedures,in a considerable proportion of patients, the "begging hand"posture can be corrected to a more functional and lessnoticeable position. Key words: Obstetric palsy, brachialplexus, supination deformity, osteotomy, brachioradialisre-routing pronotoplasty.