Long-term electromyography-based virtual reality training for chronic upper-limb motor paralysis after stroke: an exploratory single-case experimental design.

INTRODUCTION

Stroke commonly causes various symptoms, such as motor paralysis. Limited motor recovery during the chronic stage of stroke is a challenge in rehabilitation. Motor training using myoelectric pattern recognition (MPR) and virtual reality (VR) may improve maladaptive sensorimotor integration, thereby promoting motor recovery after stroke (MVR training). We evaluated the feasibility of adding upper-limb MVR training to conventional rehabilitation therapy for >3 months in individuals with chronic motor paralysis after stroke.

METHODS

Two individuals with chronic stroke participated in this preliminary, single-case study. An open-label, repeated-measures design was used for Participant A, and an ABA-type single-case experimental design was used for Participant B. During the intervention period (Participant A: 40 sessions over 8 months; Participant B: 20 sessions over 3 months), participants underwent MVR training in addition to conventional rehabilitation care. During MVR training, the participants performed the posture-matching test (30 min, twice a week), requiring them to voluntarily move their paretic hand with real-time visual feedback of the virtual hand that was controlled by the MPR of the paretic upper-limb muscles.

RESULTS

Both participants completed the planned training sessions without serious adverse events. The Fugl-Meyer assessment score of the upper extremities was used to assess upper-limb motor function. Following VR training, the improvement from baseline exceeded the estimated minimal clinically important difference in Participant A (+7 points) but not in Participant B (+5 points).

DISCUSSION: In conclusion, these findings suggest that long-term MVR training is feasible and can be implemented without serious adverse events in individuals with chronic motor paralysis after stroke. Although improvement in upper-limb motor function was observed in one participant, further studies with larger samples and controlled designs are warranted to assess the efficacy of MVR training.