Electrophysiologic recovery of the abductor pollicis brevis after contralateral C7 nerve transfer in 95 patients with global brachial plexus avulsion

In this study, we investigated the electrophysiologic recovery of the abductor pollicis brevis (APB) muscle after contralateral seventh cervical (cC7) nerve transfer for the treatment of global brachial plexus avulsion (GBPA). We retrospectively analyzed the electromyography records of 95 patients with GBPA, comprising 81 men and 14 women, focusing on the motor unit potential (MUP) recovery of the APB. All patients underwent cC7-median nerve (MN) transfer. The cC7 nerve was transferred to the MN alone in 58 patients (One-Nerve Group), whereas 37 patients underwent cC7 transfer to the MN and another nerve (Two-Nerve Group). Fifty-three patients (MUP Group) exhibited MUP recovery of the APB, whereas 42 patients did not (No-MUP Group). The MUP Group comprised 31 patients from the One-Nerve Group and 21 patients from the Two-Nerve Group. The mean age of the MUP Group was significantly lower than that of the No-MUP Group. In summary, electrophysiologic recovery of the APB was common in patients with GBPA after cC7-MN transfer, indicating that it may be possible to restore the function of the intrinsic muscles of the hand after GBPA. The rehabilitation strategy for patients with GBPA, which overlooks the restoration of intrinsic hand muscle function, may require amendment.