Eligibility CriteriaInclusion criteria:
- Male or female over the age of 18 who experienced no more than one ischemic or hemorrhagic stroke, at least 6 months ago resulting in hemiparesis in one upper extremity
- Upper extremity Fugl Meyer score >10- - subject must score at least a 10 on the UE FM at the baseline screening appointment only.
- Moderate to Low Tone (Modified Ashworth Score <= 3) If there is too much background contraction in the arm, the system will be unable to pick up voluntary contraction from the background noise, and the brace may not be strong enough to counter the muscle tone. Subject's Modified Ashworth at the screening evaluation score should be < 3
- Considered medically stable- medical conditions that are not under control may affect the subject's ability to participate in treatment sessions safely.
- Able to participate in 17 one hour treatment sessions and willing to complete the evaluations- subjects must be willing to attend all evaluation and treatment sessions
- Score < 3 rating of shoulder pain on the visual analog scale (Appendix N) - subjects must be able to safely tolerate the weight of the brace (about 2 lbs) during treatment sessions.
- Brace fits on arm properly and without discomfort (No red marks or discomfort observed in 10 minutes of use)- subjects need to be able to tolerate sessions with the device
- There is a detectable EMG signal in bicep and tricep and the subject is able to use the brace volitionally- Some voluntary muscle activity must exist for the system to be controlled by the subject due to the non-invasive, surface EMG, sensing methodology.
Exclusion Criteria- A current medical history of uncontrolled cardiovascular, or pulmonary disease, or other disease that would preclude involvement in a therapeutic treatment - Subjects must be able to tolerate a 45 minute upper-extremity therapy session in order to participate.
- History of neurological disorder other than stroke- other neurological disorders may affect the upper extremity motor performance of subjects.
- Other significant pain or skin irritation in the upper extremity that would be exacerbated if by the use of the brace - While wearing the brace, the system is pressed close to the upper arm and strapped around it. If the subject suffers from dermal breakdown or other skin conditions that may be aggravated by such a situation, they should not be involved in the study.
- Substantial contracture of elbow - The system cannot work in the presence of reduced range of motion due to contractures. A substantial contracture is defined as greater than 20 degrees of elbow flexion contracture measured at the baseline evaluation.
- Severe sensory loss: Score of 2 on the NIH stroke scale for sensory impairment. The system can work on subjects with sensory loss, however the concern is that a subject with severe sensory loss would not know if the system was applying too much force to the arm or if a strap was too tight and therefore not be able to inform their clinician.
- Use of Botox injections in shoulder, arm or hand for the 3 months prior to study start and throughout the duration of the research study. - the use of Botox may alter the subject's performance on upper extremity motor tasks that are being assessed in the research
- Cognitive or perceptual deficits sufficiently severe enough to interfere with ability to follow instructions- If the subject is unable to understand and follow simple instructions or express if the presence of pain, they should not be included. If the subject scores <69 on the Modified Mini Mental Exam or, if in the opinion of the principle investigator the subject can not safely participate in the study, the subject will be excluded.