Prevention of Post-Stroke Hand/Wrist Flexion Deformity

BION™ Experimental Group Following implantation, the patients receiving BIONs will have a 3 to 7 day healing period. During this period, subjects will not receive active therapy. At the end of this healing period, subjects will come to the testing center so that the examiner can program the exercise patterns. They will be instructed to increase the strength of their muscle contractions as tolerance permits. The goal for the BION™ patients is to achieve 30 minutes of stimulation twice daily, using a cycled stimulation at frequencies adequate to produce tetanic contraction, (typically 25-35 pps) that raises the joint through full range of motion against gravity (a range graded as 3/5) based on the available range of motion. The intensity, duration and frequency of the exercise program will be modified according to the progress of the participant, so that the strength of the contraction is increased over time. Surface Stimulation Group Patients will be instructed to stimulate twice daily for 30 minutes through surface electrodes placed according to instructions that the subject has been given. Stimulus parameters will be similar to those reported in earlier successful stimulation studies. The parameters should achieve a tetanic contraction that raises the joint through full range of motion against gravity (graded 3/5) based on the patient's available range of motion, and cycled, typically at 25-35 pps, using stimulus ramps as necessary so that contractions are smoothly graded and comfortable. Every effort will be made to ensure that the parameters needed in this group are chosen to produce a similar type of contraction to that obtained with BION™ stimulation. Control Group with conservative therapy (Range of motion exercises) The research participant is instructed in self-administered, standard range of motion stretching exercises. If the patient is unable to stretch the fingers into extension, a family member or a care-giver will be instructed to assist. They will be instructed to exercise the affected hand twice daily, repeating the exercise a minimum of 15 times in each session for 6 weeks. Control subjects will return to the clinic every two weeks for the first 6 weeks and every 3 weeks during the follow-up period. During these visits, passive range of motion testing will be administered.