Clinical Sciences/Health Conditions
Syoichi Tashiro, MD, PhD (he/him/his)
Department of Rehabilitation Medicine
Kyorin University School of Medicine
Mitaka, Tokyo, Japan
Mitsuaki Takemi, PhD
Associate ProfessorProfessor
Hiroshima University
Hiroshima, Hiroshima, Japan
Shin Yamada, MD, PhD
Professor
Kyorin University School of Medicine
Mitaka, Tokyo, Japan
Tetsuya Tsuji, MD, PhD
Professor
Keio University School of Medicine
Shinjuku, Tokyo, Japan
Chronic hand paresis is one of important stroke sequelae. Although neurorehabilitation utilizing electrical stimulation targeting either the brain or periphery has become common, integrating both approaches remains underexplored.
Design:
This double-blind, randomized crossover trial investigated the safety and feasibility of combining transcranial alternating current stimulation (tACS) targeting the cortex with neuromuscular electrical stimulation (NMES) applied to the periphery. The intervention was formed into a one-hour weekly outpatient rehabilitation program, including conventional occupational therapy. The tACS was applied at the primary motor cortex to boost the post-movement beta-rebound following the finger-extension training task assisted by NMES. The precision stimulation principle was incorporated in tACS in terms of the timing of the training task, focality of the montage, individualized frequency of the AC, and in the NMES set to amplify the detected activity of the paretic muscle correctly using a hybrid electrode for detection and stimulation. The result on behavioral and physiological assessments were compared between Real-tACS and Sham-tACS interventions.
Results:
Ten participants completed ten weekly sessions, and no remarkable adverse events were recorded. After the real-tACS sessions, participants reported less sleepiness (p = 0.037, r = 0.66, t-test), and the weak incrementation of stress measured by heart rate variability (p = .010, r=1.19, t-test), and the endurance to repeat training tasks, as measured by the transition of detected electromyography, was higher (F[1,18] < 2.05, p < 0.001, repeated-measures ANOVA). Scores of the Fugl-Meyer upper extremity (FMA)and Action Research Arm Test (ARAT) showed enhanced motor recovery in the real-tACS intervention compared to sham (FMA: pre, 27 [19-29.75]; post 30 [22.5-33.75], p = .043, r = 1.00; ARAT: pre, 6 [4-14.75]; post 8 [5-16.5]).
Conclusion:
Findings support the safety and feasibility of combining the two modalities of electrical stimulation, tACS and NMES, in stroke rehabilitation, highlighting its potential effectiveness.
