Locomotion via paralyzed leg muscles: feasibility study for a leg-propelled vehicle.

Functional electrical stimulation has been used to restore some degree of controllable movement to paralyzed muscle. The purpose of this study was to demonstrate the feasibility of using electrically stimulated paralyzed leg muscles to propel a wheelchair-type vehicle. For this, a conventional manual wheelchair was modified by the addition of a drive system which permits forward propulsion by reciprocating movements of the legs. A battery-powered electrical stimulator using surface electrodes over the quadriceps muscles controls locomotive characteristics. This vehicle has been successfully operated by paraplegic and quadriplegic test subjects. Advantages of using paralyzed leg muscles for locomotion may include improvement in locomotive capability, circulation in the lower extremities, cardiovascular and respiratory fitness, strength and size of the exercised muscles and bones, and self-image.