Therapies for Recovery of Hand Function After Stroke

Inclusion Criteria: * 6 to 24 months since a first clinical cortical or subcortical, hemorrhagic or nonhemorrhagic stroke * unilateral upper limb hemiparesis with finger extensor strength of grade no more than 4 out of 5 on the Medical Research Council (MRC) scale * score of at least 1 and no more than 11 out of 14 on the hand section of the upper extremity Fugl-Meyer Assessment * adequate active movement of the shoulder and elbow to position the hand in the workspace for table-top task practice (necessary for the lab task practice sessions) * able to follow 3-stage commands * able to recall at least 2 of a list of 3 items after 30 minutes * skin intact on the hemiparetic arm * surface stimulation of the paretic finger and thumb extensors produces functional hand opening without pain (this will exclude those who have too much flexor spasticity) * able to hear and respond to cues from stimulator * not receiving occupational therapy (no concomitant OT) * full voluntary opening/closing of the contralateral (less affected) hand * demonstrates ability to follow instructions for operating the stimulator or have a caregiver who will assist them Exclusion Criteria: * co-existing neurologic diagnosis of peripheral nerve injury, Parkinson's disease, spinal cord injury, traumatic brain injury, or multiple sclerosis * uncontrolled seizure disorder * brainstem stroke * uncompensated hemineglect * severe shoulder or hand pain * insensate forearm or hand * history of potentially fatal cardiac arrhythmias with hemodynamic instability * implanted electronic systems (e.g. pacemaker) * botulinum toxin injections to any upper extremity muscle within 3 months of enrolling * pregnant women due to unknown risks of surface NMES during pregnancy * lack of functional passive range of motion of the wrist or fingers of affected side * diagnosis (apart from stroke) that substantially affects paretic arm and hand function * deficits in communication that interfere with reasonable study participation * lacking sufficient visual acuity to see the stimulator's display * concurrent enrollment in another investigational study