Synergy effects of combined multichannel EMG-triggered electrical stimulation and mirror therapy in subacute stroke patients with severe or very severe arm/hand paresis

Background: Neurorehabilitation requires the development of severity-dependent and successful therapies for arm/hand rehabilitation in stroke patients. Objective: To evaluate the effectiveness of adding mirror therapy to bilateral EMG-triggered multi-channel electrostimulation for the treatment of severe arm/hand paresis in stroke patients. Methods: The subjects of this randomized, controlled, multicentre study were stroke patients who had suffered their first insult between 1 and 6 months before study start and had severe or very severe arm/hand paresis, as classified by Fugl-MeyerAssessment. Subjects were randomly allocated to an intervention group (n = 16) or control group (n = 17). Both groups were treated for 3 weeks (5x week, 30 minutes) with bilateral EMG-triggered multi-channel electrostimulation. The intervention group additionally received mirror feedback of the unaffected limb. The primary outcome measure was motor recovery of the upper extremities, as measured by the Fugl-Meyer Assessment. Results: The Intervention Group with very severe paresis had significantly better motor recovery in total Fugl-Meyer Assessment (p = 0.017) at a medium effect size (Cohen) of d = 0.7, due to a significant recovery of shoulder and elbow function (p = 0.003) in the Fugl-Meyer Assessment Part A subtest. For subjects with severe paresis, additional mirror therapy did not significantly influence outcome. Conclusion: Additional mirror therapy in combination with EMG-triggered multi-channel electrostimulation is therapeutically beneficial for post-acute stroke patients with very severe arm/hand paresis.