The Nerves to Stand Up

A type of "nerve cuff" technology invented by two Case Western Reserve University biomedical engineers promises to some day orchestrate the stepping motion that will allow wheelchair-bound individuals to walk. It may also one day interpret the brain's thought cues to control prostheses, allowing a person to pilot an artificial limb by simply thinking about a movement, with help from a tiny decoding sensor embedded in the brain or in the nerves.

A recent study by one of the technology's inventors, Dustin Tyler, PhD, of Case Western Reserve and the Louis Stokes Cleveland VA Medical Center, shows the nerve cuff could have some real advantages to offer in the near term as well.

Before long, it could help those who are paralyzed to shift in their wheelchairs, avoiding painful and dangerous pressure sores, and enable them to stand up—a triumphant stride toward independence. "The nerve cuff would allow a person in a wheelchair to stand and grab something out of the cupboard," Tyler says of the technology he invented several years ago with Dominique Durand, PhD, of the university's Neural Engineering Center.

In most other devices under review to mobilize paralyzed arms or legs, electrodes are attached directly to muscles. However, Tyler and Durand's model—which is moving from computer simulations to the early stages of human testing—attaches multiple electrical contacts to a single nerve to trigger movement. For standing, the cuff stimulates six major muscles simultaneously for a powerful effect beyond that of direct muscle activation.

The team's recent study shows the nerve cuff could selectively stimulate just the right nerves for standing. Results of the study will be published in an upcoming issue of the Journal of Neural Engineering.