[Pectoralis major muscle transfer for reconstruction of elbow flexion in posttraumatic brachial plexus lesions].

OBJECTIVE: Active elbow flexion is necessary for bimanual tasks. Reconstruction of powerful active elbow flexion. Reconstruction of missing muscle unit by neurovascular pedicled functional muscle transposition. INDICATIONS: Treatment of second choice (first choice bipolar latissimus dorsi transfer according to Zancolli & Mitre, transfer of the flexor/pronator muscle onto the distal humerus, or transposition of the triceps onto the biceps): --(Secondary) reconstruction of active elbow flexion in case of lesion of the brachial plexus or musculocutaneous nerve. --Replacement of the elbow flexor muscles in case of primary muscle loss (tumor, trauma). CONTRAINDICATIONS: Ongoing spontaneous or postoperative nerve regeneration. Ankylosis of the elbow joint (in case of good shoulder and hand function, one should consider arthrolysis or even total joint replacement). Insufficient power of the pectoralis major muscle (< M(4)). Lesion of the axillary artery involving the thoracoacromial artery. Relative: concomitant lesion of the latissimus dorsi and teres major muscles (loss of glenohumeral adduction [thoracohumeral pinch]. SURGICAL TECHNIQUE: Distal muscle transposition: transposition of the origin--pars abdominalis, pars sternocostalis, pars clavicularis (unipolar or bipolar, partial or complete distal transfer): --Unipolar partial pectoralis major muscle transposition according to Clark. --Bipolar partial pectoralis major muscle transposition according to Schottstaedt et al. --Bipolar complete pectoralis major muscle transposition according to Dautry et al. and Carroll & Kleinmann, respectively, possibly in combination with transfer of the pectoralis minor muscle. --Myocutaneous flap in case of concomitant skin defect at the upper arm level. Proximal tendon transfer: transposition of the tendinous insertion at the humerus of the pectoralis major muscle. POSTOPERATIVE MANAGEMENT: Immobilization for 6 weeks in a dorsal upper arm splint, a Gilchrist bandage or a thorax-arm abduction orthesis with the elbow in 90 degrees flexion and supination. Early passive motion depending on pain within the sector 90-140 degrees. Progressive increase of active range of motion after 6 weeks. Protected exercise from "out of the splint" with increasing elbow extension of 10 degrees per week. It is important, that there is still an extension lag of 30-40 degrees at 3 months after transfer, in order to protect the reinnervated muscle and avoid overstretching. Although complete elbow extension should be the aim after 1 year, most patients will keep an extension lag of 20-30 degrees. Physiotherapy must continue for 12-18 months. Postoperative standardized compression therapy, combined with scar therapy (silicone sheet).
RESULTS: Meta-analysis of the literature and personal results show functional (very good and good) results in 54-86% of patients. There are only few complications.