Outcomes From Radial Fascicular Nerve Transfers Including Extensor Carpi Radialis Longus to Triceps for Elbow Extension.

Abstract

Reconstruction of elbow extension is an important aim after brachial plexus injury. In extended partial brachial plexus injuries affecting elbow extension, a variety of nerve transfer techniques have been described to neurotize triceps. Spinal accessory, ulnar fascicles, axillary branches, intercostal and phrenic nerves have all been reported. These donors have mostly been transferred to triceps brachii nerves; however, more proximal transfers have also been reported. Results with these techniques have been inconsistent. In extensive partial brachial plexus palsy, radial fascicular transfers, primarily aiming for the extensor carpi radialis longus (ECRL) fibers as donors, warranted further investigation for their efficacy in the restoration of elbow extension. Single-surgeon case series of four consecutive patients (mean age: 32 years, range 22-46 years) over a 5-year period with traumatic brachial plexus palsies, including complete triceps weakness, underwent radial fascicular transfers incorporating ECRL donor fibers direct to triceps nerves. All had previously undergone nerve transfers for restoration of elbow flexion and shoulder function. Expendable radial fascicles (primary to ECRL with possible inclusion of other extensors including ECRB) were coapted to motor branches of triceps (medial or lateral head) using standard microsurgical techniques. All patients were followed clinically (mean: 19 months) and assessed for elbow extension strength (Medical Research Council grade), range of motion and any donor-site deficits. All patients regained functional elbow extension. Mean follow-up was 19 months (range 10-24 months). At final follow-up, elbow extension strength was MRC ≥ 4/5 in all cases (three patients achieved MRC grade 4/5, one achieved MRC grade 5/5). Elbow active range of motion reached was excellent. There were no wrist or finger extensor weakness/donor site deficits or postoperative surgical complications. Radial fascicular transfers using ECRL donor fibers direct to triceps nerves represent a safe and effective surgical technique for the restoration of elbow extension. As demonstrated in these 4 consecutive successful cases, patients with brachial plexus palsy including triceps palsy with preserved function in wrist extensors warrant consideration for this technique.