Electrical Stimulation for Upper Limb Recovery in Stroke

Stroke is the leading cause of activity limitation among older adults in the United States. NeuroMuscular Electrical Stimulation (NMES) can be used by stroke survivors who do not have enough residual movement to take part in volitional active repetitive movement therapy and does not require expensive equipment or skilled personnel. Two types of NMES are available. The first is cyclic NMES, which electrically activates paretic muscles at a set duty cycle for a preset time period. (This study will employ both "traditional" cyclic stimulation and "sensory-only" stimulation, in which intensity is set at a level to be felt by the patient but insufficient to cause muscle contraction.)In cyclic NMES, the patient is a passive participant and does not assist the NMES by volitionally contracting the muscle during stimulation. The second type encompasses various forms of NMES in combination with biofeedback. For example, in "EMG-triggered" NMES, subjects are "rewarded" with stimulation in response to successful attempts to reach a pre-set level of EMG activity in the affected muscle. There is increased cognitive input and involvement on the part of the patient. The purpose of this study is to first demonstrate the effectiveness of these two types of surface stimulation on decreasing motor impairment and activity limitation; the study also seeks to assess the effect of adding cognitive input to NMES to reduce motor impairment and activity limitation.

Study subjects will be acute stroke survivors. They will participate for a total of eight months, beginning within the first six months after their stroke. Subjects will be randomly assigned to one of three treatment groups and will receive stimulation accordingly: 1) Cyclic stimulation; 2)Sensory-only stimulation; and 3)EMG-triggered stimulation. Members of each treatment group will be given an appropriate NMES device to use for two 40-minute treatment sessions per day, five times per week for eight weeks; for a total of 80 treatment sessions. Stimulation will be applied to ECR and EDC (wrist and finger extensors) on the affected arm. A treatment therapist will visit the patient at home on a weekly basis to monitor subject compliance and to provide feedback on device usage. The primary outcome measure will be the upper extremity portion of the Fugl-Meyer Motor Assessment (FMA), a measure of motor impairment. The modified Arm Motor Ability Test (mAMAT) is a hemiparetic arm-specific measure of activity limitation, and will serve as a secondary outcome measure.

In addition to the baseline visit on day of enrollment, subjects will complete these outcome measurements at the clinic on five other occasions: at mid-treatment (week 5); end of treatment (week 9); and for follow-up visits at one-, three- and six-months post-treatment.