The Journal of Neurosurgery published a case report this week on an emerging procedure which allows doctors to transfer working nerves to other locations in the body where nerve function has been lost, thus restoring movement. The study highlights the treatment’s success by describing one patient who underwent this procedure to regain hand function after a 2008 vehicle accident left him with a crushed spinal cord at the C7 vertebrae.
This spinal cord injury (SCI) severed the nerves that would normally send signals from his brain to the muscles in his hands, leaving him unable to use them. However, the accident spared nerves that were close, enabling doctors to utilize those to restore hand function.
ABC News explains that those with C7 spinal cord injuries lose the ability to move their hands, although they retain shoulder, elbow, and wrist movement due to nerves that begin above the injury. In this patient’s procedure, they cut the nerve which controls the brachialis, an arm muscle that helps bend the elbow. Doctors then “attached it to the non-working nerve projecting out to his hand with a tiny stitch the size of a hair,” ABC explains.
Doctors said this nerve could be sacrificed because other muscles would compensate for the missing brachialis function. After six months, this borrowed nerve grew another six inches along the path of the non-functioning nerve and reached the muscles of the hand. Following intense physical therapy, this patient learned to once again move his fingers with this borrowed nerve.
This technique seizes on the peripheral nerves’ ability to regenerate, which nerves inside the spinal cord cannot do. Peripheral nerves are those which transmit signals between muscles and the spinal cord.
Researchers and surgeons believe this process could offer up a new option to restore some of the lost independence of SCI patients. Despite the adaptive strategies many of these patients may have developed, this procedure could help many surpass previous physical limitations due to nerve damage.
However, ABC points out that this procedure cannot help all SCI patients. For those with injuries higher up on their spinal cord, doctors do not have the extra muscles to borrow nerves from because so many no longer work.
The authors also note that despite the positive findings with the focus patient, further research is needed to “assess reliable clinical outcomes and optimal timing for surgical intervention.” Nevertheless, the researchers point out that for those who undergo brachialis nerve transfer, they tend to continue recovering increasing amounts of motor power after their surgery.