Electromyographic versus rhythmic positional biofeedback in computerized gait retraining with stroke patients

Abstract

This research provides a preliminary investigation of the relative efficacy of electromyographic (EMG) versus a novel biofeedback (BFB) approach to improve ankle control and functional gait in stroke patients. A computerized system was designed to provide audiovisual feedback of either muscle activity or ankle position during dorsiflexion and plantar flexion. The novel approach also included rhythmic pacing to emphasize the rapid timing of ankle motion necessary to switch from stance to swing during walking. Thirty-seven subjects were randomly assigned to one of the following groups: (1) no-treatment control, (2) EMG BFB, and (3) rhythmic positional BFB. Blind evaluations of ankle performance, gait, and perceived exertion were performed at regular intervals. Analyses of covariance revealed that subjects receiving rhythmic positional BFB significantly increased their walking speeds relative to other groups at posttest (p = .02) and at three-month follow-up (p = .035), without any increase in subjectively reported energy cost. The ability of positional BFB to emphasize the timing events during walking provided optimistic results for carry-over into gait functioning. The degree of sensorimotor recovery and time since onset of stroke were considered important factors in determining outcomes.