Functional and neuromuscular changes induced via a low-cost, muscle-computer interface for telerehabilitation: A feasibility study in chronic stroke

Octavio Marin-Pardo; Miranda Rennie Donnelly; Coralie S Phanord; Kira Wong; Jessica Pan; Sook-Lei Liew

doi:10.3389/fnrgo.2022.1046695

Functional and neuromuscular changes induced via a low-cost, muscle-computer interface for telerehabilitation: A feasibility study in chronic stroke

Front Neuroergon. 2022 Nov 17:3:1046695. doi: 10.3389/fnrgo.2022.1046695. eCollection 2022.

Authors

Octavio Marin-Pardo¹, Miranda Rennie Donnelly², Coralie S Phanord², Kira Wong², Jessica Pan³, Sook-Lei Liew^{1

2

4}

Affiliations

¹ Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States.
² Chan Division of Occupational Science and Occupational Therapy, University of Southern California, Los Angeles, CA, United States.
³ Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, CA, United States.
⁴ Stevens Neuroinformatics Institute, Department of Neurology, University of Southern California, Los Angeles, CA, United States.

Abstract

Stroke is a leading cause of adult disability in the United States. High doses of repeated task-specific practice have shown promising results in restoring upper limb function in chronic stroke. However, it is currently challenging to provide such doses in clinical practice. At-home telerehabilitation supervised by a clinician is a potential solution to provide higher-dose interventions. However, telerehabilitation systems developed for repeated task-specific practice typically require a minimum level of active movement. Therefore, severely impaired people necessitate alternative therapeutic approaches. Measurement and feedback of electrical muscle activity via electromyography (EMG) have been previously implemented in the presence of minimal or no volitional movement to improve motor performance in people with stroke. Specifically, muscle neurofeedback training to reduce unintended co-contractions of the impaired hand may be a targeted intervention to improve motor control in severely impaired populations. Here, we present the preliminary results of a low-cost, portable EMG biofeedback system (Tele-REINVENT) for supervised and unsupervised upper limb telerehabilitation after stroke. We aimed to explore the feasibility of providing higher doses of repeated task-specific practice during at-home training. Therefore, we recruited 5 participants (age = 44-73 years) with chronic, severe impairment due to stroke (Fugl-Meyer = 19-40/66). They completed a 6-week home-based training program that reinforced activity of the wrist extensor muscles while avoiding coactivation of flexor muscles via computer games. We used EMG signals to quantify the contribution of two antagonistic muscles and provide biofeedback of individuated activity, defined as a ratio of extensor and flexor activity during movement attempt. Our data suggest that 30 1-h sessions over 6 weeks of at-home training with our Tele-REINVENT system is feasible and may improve individuated muscle activity as well as scores on standard clinical assessments (e.g., Fugl-Meyer Assessment, Action Research Arm Test, active wrist range of motion) for some individuals. Furthermore, tests of neuromuscular control suggest modest changes in the synchronization of electroencephalography (EEG) and EMG signals within the beta band (12-30 Hz). Finally, all participants showed high adherence to the training protocol and reported enjoying using the system. These preliminary results suggest that using low-cost technology for home-based telerehabilitation after severe chronic stroke is feasible and may be effective in improving motor control via feedback of individuated muscle activity.

Keywords: biofeedback; electromyography; human-computer interface; stroke; telerehabilitation.