May Dual Transcranial Direct Current Stimulation Enhance the Efficacy of Robot-Assisted Therapy for Promoting Upper Limb Recovery in Chronic Stroke?

Abstract

Objective To assess whether dual transcranial direct current stimulation (tDCS) may enhance the efficacy of exoskeleton robotic training on upper limb motor functions in patients with chronic stroke. Methods A prospective, bi-center, double-blind, randomized clinical trial study was performed. Patients with moderate-to-severe stroke (according to The National Institute of Health Stroke Scale) were randomly assigned to receive dual or sham tDCS immediately before robotic therapy (10 sessions, 2 weeks). The primary outcome was the Fugl–Meyer for Upper Extremity, assessed before, after, and at the 12-week follow-up. Neurophysiological evaluation of corticospinal projections to upper limb muscles was performed by recording motor evoked potentials (MEPs). ClinicalTrials.gov-NCT03026712. Results Two hundred and sixty individuals were tested for eligibility, of which 80 were enrolled and agreed to participate. Excluding 14 dropouts, 66 patients were randomly assigned into the 2 groups. Results showed that chronic patients were stable before treatment and significantly improved after that. The records within subject improvements were not significantly different between the 2 groups. However, a post-hoc analysis subdividing patients in 2 subgroups based on the presence or absence of MEPs at the baseline showed a significantly higher effect of real tDCS in patients without MEPs when compared to patients with MEPs ( F = 4.6, P = .007). Conclusion The adjunction of dual tDCS to robotic arm training did not further enhance recovery in the treated sample of patients with chronic stroke. However, a significant improvement in the subgroup of patients with a severe corticospinal dysfunction (as suggested by the absence of MEPs) suggests that they could benefit from such a treatment combination.

Transcranial direct current stimulation for upper extremity motor dysfunction in poststroke patients: A systematic review and meta-analysis

“…The included studies 18–61 involved 1555 patients (experimental group: 820, control group: 715) and were published between 2010 and 2024 in 20 countries. The top three countries based on the number of research studies were Italy ( n = 10), China ( n = 9), and the United States ( n = 5).…”

“…Taud et al 53 utilized anodal and bilateral stimulation for the experimental groups, while Qu et al 46 employed 1 and 2 mA of cathodal stimulation for the experimental groups. Fifteen studies 21,22,24–26,29,32,37,38,42,47,50,55,56,61 exclusively utilized anodal stimulation for the experimental group, 19 18–20,23,28,31,34–36,39,41,43,45,51,52,54,57,58,62 exclusively utilized bilateral stimulation for the experimental group, and four 27,40,48,59 exclusively utilized cathodal stimulation for the experimental group (Table 1). Additionally, 39 studies 18–23,26–28,30–40,42…”

“…Fifteen studies 21,22,[24][25][26]29,32,37,38,42,47,50,55,56,61 exclusively utilized anodal stimulation for the experimental group, 19 [18][19][20]23,28,31,[34][35][36]39,41,43,45,51,52,54,57,58,62 exclusively utilized bilateral stimulation for the experimental group, and four 27,40,48,59 exclusively utilized cathodal stimulation for the experimental group (Table 1). Additionally, 39 studies [18][19][20][21][22][23][26][27][28][30][31]…”

Neurophysiological and Clinical Effects of Upper Limb Robot-Assisted Rehabilitation on Motor Recovery in Patients with Subacute Stroke: A Multicenter Randomized Controlled Trial Study Protocol

“…On the contrary, less affected subjects have the possibility to perform, even without a robot, adequate arm training in terms of dose and task specificity. Following these considerations, there is the need for a well-powered randomized controlled study (RCT) that identifies subject characteristics for exoskeleton-based UL-RAT [ 9 , 10 ] in subjects affected by stroke in their subacute phase.…”

Post-Stroke Rehabilitation: Challenges and New Perspectives

“…Despite these advancements there is still little consensus on which approach is the most effective for each category of patient, among the plethora of novel solutions including those based on robotics, non-invasive brain stimulations, [ 6 ] brain–computer interfaces [ 7 ], and more. In other words, while many of these approaches have proven some level of efficacy, even in well-designed randomized controlled trials (RCTs), most patients are offered these options according to their availability in the facilities that they refer to for rehabilitation with the certainty that they will do no harm and in the presumption that they will contribute to a better outcome.…”