Abstract 122: AMES Treatment of Severe Hand Impairment Following Stroke
The objective of this study was to determine whether AMES (Assisted Movement with Enhanced Sensation), a novel therapeutic intervention that addresses impairments, rather than function, can reduce impairment and restore lost function in persons with a severely disabled hand. Forty-three participants with stroke (>1 yr post-injury) were provided with thirty 30-min AMES treatments over 10 weeks. Of these participants, 24 had no baseline active extension of any finger of the affected hand. Participants were randomized to 1 of 2 treatment groups differentiated by the kind of biofeedback (active torque or EMG) associated with the AMES intervention. During treatment, a robotic device cyclically opened and closed the hand (5 deg/s, ±15 deg) while the participant assisted this movement using visual biofeedback, and while vibration (60 pulses/s, 2 mm) was applied to the lengthening muscles. Participants were evaluated twice, before and after the treatment period, with the Fugl-Meyer Assessment (FMA-UE), Stroke Impact Scale (SIS), and Box-and-Block Test. In addition, during each treatment session, the AMES robot tested each participant’s strength of thumb-and-finger flexion and extension. Both torque and EMG were recorded during this Strength Test in participants assigned to the EMG-biofeedback group. The results showed overall a significant increase in the FMA-UE score (t-test, p<0.001), SIS score (t-test, p<0.05), and Box-and-Block Test score (Wilcoxon, p<0.005), without any difference between the 2 treatment groups. Four of the 24 initially plegic participants recovered the ability to move one or more blocks; however, all participants showing improvement in the Box-and-Block Test had a baseline FMA score of ≥17. Analysis of EMG during the hand-opening part of the Strength Test showed that AMES treatment of the EMG-biofeedback group significantly increased the amplitude of extensor activity (t-test, p<0.001) and decreased flexor co-contraction (t-test, p<0.05). We conclude that AMES coupled with either type of biofeedback may be effective at reducing impairment and increasing function in the severely impaired hand following stroke.
- © 2012 by American Heart Association, Inc.