Surgeons reroute nerves to restore hand, arm movement to quadriplegic patients

October 15, 2015

A nerve transfer bypasses the zone of a spinal cord injury (C7). Functional nerves (green) that are under volitional control are rerouted (yellow) to nerves (red) that come off below the spinal cord injury. (credit: Washington University in St. Louis)

A pioneering surgical technique has restored some hand and arm movement to nine patients immobilized by spinal cord injuries in the neck, reports a new study at Washington University School of Medicine in St. Louis.

Bypassing the spinal cord, the surgeons rerouted healthy nerves sitting above the injury site, usually in the shoulders or elbows, to paralyzed nerves in the hand or arm. Once a connection was established, patients underwent extensive physical therapy to train the brain to recognize the new nerve signals, a process that takes about 6–18 months.

The technique targets patients with injuries at the C6 or C7 vertebra, the lowest bones in the neck. It typically does not help patients who have lost all arm function due to higher injuries in vertebrae C1 through C5.

“Physically, nerve-transfer surgery provides incremental improvements in hand and arm function. However, psychologically, these small steps are huge for a patient’s quality of life,” said the study’s lead author, Ida K. Fox, MD, assistant professor of plastic and reconstructive surgery.

One of the most humbling effects of spine damage is the inability to manage bladder or bowel functions. “People with spinal cord injuries cannot control those functions because their brains can’t talk to the nerves in the lower body,” said Fox, who performs surgeries at Barnes-Jewish Hospital.

The study is published in an open-access paper in the October issue of the American Society of Plastic Surgeons’ journal, Plastic and Reconstructive Surgery.

Ultimately, medical professionals hope to discover a way to restore full movement to the estimated 250,000 people in the U.S. living with spinal cord injuries. More than half of such injuries involve the neck. However, until a cure is found, progress in regaining basic independence in routine tasks is important.

Abstract of Nerve transfers to restore upper extremity function in cervical spinal cord injury: Update and preliminary outcomes

Background: Cervical spinal cord injury can result in profound loss of upper extremity function. Recent interest in the use of nerve transfers to restore volitional control is an exciting development in the care of these complex patients. In this article, the authors review preliminary results of nerve transfers in spinal cord injury.

Methods: Review of the literature and the authors’ cases series of 13 operations in nine spinal cord injury nerve transfer recipients was performed. Representative cases were reviewed to explore critical concepts and preliminary outcomes.

Results: The nerve transfers used expendable donors (e.g., teres minor, deltoid, supinator, and brachialis) innervated above the level of the spinal cord injury to restore volitional control of missing function such as elbow extension, wrist extension, and/or hand function (posterior interosseous nerve or anterior interosseous nerve/finger flexors reinnervated). Results from the literature and the authors’ patients (after a mean postsurgical follow-up of 12 months) indicate gains in function as assessed by both manual muscle testing and patients’ self-reported outcomes measures.

Conclusions: Nerve transfers can provide an alternative and consistent means of reestablishing volitional control of upper extremity function in people with cervical level spinal cord injury. Early outcomes provide evidence of substantial improvements in self-reported function despite relatively subtle objective gains in isolated muscle strength. Further work to investigate the optimal timing and combination of nerve transfer operations, the combination of these with traditional treatments (tendon transfer and functional electrical stimulation), and measurement of outcomes is imperative for determining the precise role of these operations.