Objectives: Report on a new transfer for the reinnervation of biceps and brachialis muscles after multilevel avulsive injuries of brachial plexus provided at least T1 is viable: the Medial Cord to Musculocutaneous (MCMc) and its variant, the Medial Cord to anterior Upper Trunk (MC-aUT). The MC-aUT is indicated in agenesia of musculocutaneous nerve and when a residual function in the biceps is present. The MCMc transfer would be unfeasible in the former and contraindicated in the latter.
Methods: Three hundred and five consecutive patients, classified according to the quality of hand function, are available for a long-term follow-up after reconstructive surgery. They had multiple cervical root avulsive injuries at two (C5-C6), three (C5-C6-C7) and four (C5-C6-C7-C8) levels. The reinnervation was obtained via an end-to-end transfer from two donor fascicles located in the medial cord (MC) and aimed at the flexor carpi ulnaris or the flexor digitorum profundus.
Results: These transfers have no failures and no complications when the hand shows a normal function. In the case of suboptimal conditions of the hand, the technique is more challenging, but still has many satisfactory results. In the four-root avulsive injuries, on the contrary, strong limitations suggest that different strategies should be preferred. EMG shows a reinnervation in both biceps and brachialis muscles and this accounts for the quality of results. Tendon transfers for wrist and finger dorsiflexion, when required, remain unencumbered.
Discussion: The procedures are safe, effective and easily feasible. The ideal candidate has a C5-C6 injury and a normal hand function.
Keywords: Brachial plexus injury; C5-C6 palsy; Erb-Duchenne; musculocutaneous nerve; nerve transfer; root avulsion; upper plexus; upper trunk.