Multicenter evaluation of electrical stimulation systems for walking.

Abstract

To test the long-term benefits of several noninvasive systems for functional electrical stimulation (FES) during walking. Forty subjects (average years since injury, 5.4) were studied in four centers for an average time of 1 year. Gait parameters were tested for all subjects with and without FES. Thus, subjects served as their own controls, since the specific effect of using FES could be separated from improvements resulting from other factors (e.g., training). Subjects used the devices in the community, but were tested in a university or hospital setting. Subjects with spinal cord injury (n = 31) were compared to subjects with cerebral damage (n = 9). Gait parameters (speed, cycle time, stride length). Acceptance was studied by means of a questionnaire. Some initial improvement in walking speed (average increase of >20%) occurred, and continuing gains were seen (average total improvement, 45%). The largest relative gains were seen in the slowest walkers (speeds of <0.3 m/sec). Acceptance of the FES systems was good and improved systems have been developed using feedback from the subjects. Based on the improvements in speed and the acceptance of these FES systems, a greatly increased role for FES in treating gait disorders is suggested.