Susan E Mackinnon (Washington University School of Medicine, St Louis, USA) and colleagues have reported the first case of restoration of some hand function (finger and thumb flexion) in a quadriplegic patient utilising nerve transfers after cervical spinal cord injury. The case was published on 15 May in the online edition of the Journal of Neurosurgery.
Instead of operating on the spine itself, the surgeons rerouted working nerves in the upper arms. “The use of nerve transfers has gained significant momentum over the last decade and has changed the treatment algorithm in patients with nerve injuries,” Mackinnon et al wrote.
The patient is a 71-year-old man who presented spinal cord injury in the C7 level. Twenty-three months after the injury — caused in a car accident — the patient underwent bilateral transfer of the brachialis nerve (C6 level) to the anterior interosseouss nerve (AIN) (C8 level). “Surgery was performed initially on the patient’s left side and was followed one week later by surgery on the right,” the authors reported.
According to the authors, “this is the first reported case of thumb and finger flexor reinnervation after a spinal cord injury”.
“This procedure is unusual for treating quadriplegia because we do not attempt to go back into the spinal cord where the injury is,” said surgeon Ida K Fox, assistant professor of plastic and reconstructive surgery at Washington University, who treats patients at Barnes-Jewish Hospital (place where the surgery was performed). “Instead, we go out to where we know things work — in this case the elbow — so that we can borrow nerves there and reroute them to give hand function.”
After one year of intensive physical therapy, the patient regained some hand function, specifically the ability to bend the thumb and index finger. “He can now use his right hand to perform simple hand-to-mouth movements. With his left hand, he is able to feed himself and perform rudimentary writing activities,” Mackinnon et al reported.
“Our experience with this transfer in nerve injury suggests optimism for continued improvement for this patient over the next 3 years,” the authors wrote.
Mackinnon cautions that the hand function restored to the patient was not instantaneous and required intensive physical therapy. It takes time to retrain the brain to understand that nerves that used to bend the elbow now provide pinch, she said.
Though this study reports only one case, Mackinnon and colleagues do not anticipate a limited window of time during which a patient with a similar spinal cord injury must be treated with this nerve transfer technique. This patient underwent the surgery almost two years after his injury. As long as the nerve remains connected to the support and nourishment of the spinal cord, even though it no longer “talks” to the brain, the nerve and its associated muscle remain healthy, even years after the injury.
“This is not a particularly expensive or overly complex surgery,” Mackinnon said. “It is not a hand or a face transplant, for example. It is something we would like other surgeons around the country to do.”
“As Bertelli et al, have previously demonstrated, the use of nerver transfers may represent a significant breakthrough toward improved independent function in select patients with cervical spinal cord injuries.” Mackinnon et al concluded.