2 The condition, current treatments and procedure
2.1 Tetraplegia is typically caused by cervical spinal cord injuries, with associated complete or incomplete loss of muscle strength in all 4 extremities. The exact symptoms depend on the location and extent of injury. The most common neurological level of injury is the fifth cervical vertebra. This results in loss of upper limb function and the inability to carry out activities of daily living.
2.2 Restoring upper limb function is an important rehabilitation aim in people with tetraplegia. Conservative treatment options include a comprehensive program of physical and occupational therapy, including orthoses and functional electrical stimulation. Surgical techniques to restore function of the upper limb (elbow, thumb and finger extension, wrist movement, hand opening and closing, and pinch and grip) include neuroprostheses, tendon transfer, nerve transfers, reconstructive surgeries or a combination of these procedures.
2.3 In this procedure, the nearest functional undamaged and non-essential nerve is used as the donor nerve.
2.4 Under general anaesthesia, with the patient in a supine position and with their arms on a board, the non-functioning nerve is exposed and the degree of paralysis is defined neurophysiologically. The closest functional donor nerve is identified. It is then isolated, divided, transferred and joined to the selected damaged nerve while avoiding tension in the donor nerve. The aim is to re‑innervate the target muscles and improve limb function.
2.5 Post-operatively, the patient needs nerve and muscle rehabilitation training to recover the strength of the re‑innervated muscles and improve activities of daily living.
2.6 Nerve transfers may sometimes be combined with tendon transfers.