Objectives: Following tetraplegic spinal cord injury upper limb function may be improved by selective use of peripheral nerve transfers in isolation or in combination with tendon transfers. Early surgery is essential for nerves originating in the injured spinal cord segments due to Wallerian degeneration. Motor nerves arising from the infralesional segment of the injured spinal cord will have an intact peripheral neural pathway and nerve transfer may be undertaken beyond 12 months. This study evaluates the role of electromyography in planning and timing reconstruction. Methods: A consecutive series of 8 patients referred for consideration of nerve transfer surgery for restoration of upper limb function following tetraplegic spinal cord injury were evaluated with electromyography to establish volitional control, denervation, or evidence of reinnervation. For those patients undergoing surgery, further evaluation of intraoperative stimulation thresholds and motor response was recorded using a 4-point scale. Results: At our unit, we established a service for rehabilitation surgery of the upper limb after cervical spinal cord injury in 2013. Electromyography predicts lower motor unit lesions without reinnervation and early nerve transfer intervention may be offered to key target muscles in this group. For the C5/6 level tetraplegic with International Classification of Surgery of the Hand in Tetraplegia (ICHT) function at level 0 to 2, we recommend electromyography of extensor digitorum communis (EDC) and triceps to establish timing of reconstructive nerve transfers. Conclusions: Electromyography is an essential component of the preoperative assessment of patients for nerve transfer reconstruction of the upper limb after spinal cord injury. For the C5/6 level tetraplegic with ICHT function at level 0 to 2, we recommend early electromyography of EDC and triceps between 3 and 6 months from injury to establish timing of reconstructive nerve transfers.
