Treating chronic hemiparesis with modified biofeedback.

Eleven patients with chronic spastic hemiparesis were treated with biosignal processing (BSP), a modified biofeedback method in which the patient practices useful tasks, not isolated individual movements. A surface EMG measures sequential movements, and an acoustic signal monitors muscle exertion. The patient first learns how the signal develops by using the unaffected limb. Then the patient tries to reproduce the course of the signal in the paretic limb. Patients received 12 to 30 treatments for upper and/or lower extremities. We measured maximum strength as expressed through the EMG signal; ability to perform the trained action as measured by specific grading systems; and general increase in movement competence during a Bobath movement test. Ten patients showed improved strength; four made marked progress in the performance of specific tasks with the upper extremity, as did four with the lower extremity. Four patients in each group improved in general movement. We recommend the integration of useful tasks into movement exercises in EMG biofeedback therapy.