The use of brain stimulation in the rehabilitation of walking disability in patients with multiple sclerosis: A randomized double-blind clinical trial study

Abstract

Background: Transcranial direct current stimulation (tDCS) of the primary motor cortex of the lower limb has been exploited in the treatment of patients with stroke and spastic lower limb paresis. We examined this stimulation efficacy in the treatment of multiple sclerosis (MS)-related walking disability. Methods: In a single-center randomized doubleblind clinical trial study, 13 patients with MS and walking disability and Expanded Disability Status Scale (EDSS) score of 3 to 6 were randomized to the real and sham stimulation groups. In the real tDCS stimulation, 7 patients received anodal 2.5 mA stimulation at 1 cm anterior to the Cz point for 30-minute daily sessions in 7 consecutive days. The other group received sham stimulation with the same protocol. The primary outcome of the trial was change in the Timed 25-Foot Walk (T25-FW) from before to after the stimulation. We also assessed the Multiple Sclerosis Walking Scale-12 (MSWS-12). We employed linear mixed effects model to examine the efficacy of tDCS stimulation on changing the outcomes. Results: On average, patients who received real tDCS stimulation walked faster after 7 sessions of stimulation [Estimate = -2.7, standard error (SE) = 1.3, P = 0.049], while walking speed of sham stimulation recipients did not change. For every session of stimulation, recipients of real tDCS stimulation spent 2.7 seconds less for walking the 25 feet. Real tDCS stimulation was not effective in improving MSWS-12 scores. Conclusion: tDCS stimulation of the lower limb motor cortex speeded up patients with MS in walking, but without improvement in patients’ mobility in daily activities.

No Immediate Effects of Transcranial Direct Current Stimulation at Various Intensities on Cerebral Blood Flow in People with Multiple Sclerosis

“…Because some MS symptoms (e.g., neuropathic pain) are treatment-resistant [2], practical and inexpensive adjunctive therapies, like transcranial direct current stimulation (tDCS), are of high interest. Despite promising findings in tDCS studies in people with multiple sclerosis (PwMS) [3][4][5] (see [6] for a review), the validity and utility of tDCS is under scrutiny. For example, a critical review [7] did not support the idea that tDCS has a reliable neurophysiological effect beyond motor evoked potential (MEP) amplitude modulation.…”

Walking in multiple sclerosis improves with tDCS: a randomized, double‐blind, sham‐controlled study

“…18 The authors found a decrease in distance walked in the "during" group and an increase in gait velocity in the "before" group. 18 A previous study using tDCS alone found an increase in gait velocity in the active versus the sham group following seven sessions, 19 but without any corresponding change in self-reported outcomes (MSWS-12 score). Taken together, the present findings suggest that tDCS should be paired with simultaneous exercise or motor training and should include extended treatment with multiple sessions to lead to measurable benefits.…”

“…Our results are in line with recent reports that proposed NIBS, and tDCS paired with exercise training specifically, to augment or potentiate the benefits induced by physical activity in Parkinson's disease, 39 cerebellar ataxia, 40 and cerebral palsy. 41 Two previous studies have tested anodal tDCS to treat walking impairment in patients with MS, 18,19,21 evaluating outcomes after only one session of tDCS paired with a motor activity 18 or using tDCS only (without paired activity) for five sessions. 21 Most recently, the timing window of tDCS application was assessed using the 6-minute walk test in 12 patients with MS either before or during stimulation.…”

“…Two previous studies have tested anodal tDCS to treat walking impairment in patients with MS, 18,19,21 evaluating outcomes after only one session of tDCS paired with a motor activity 18 or using tDCS only (without paired activity) for five sessions 21 . Most recently, the timing window of tDCS application was assessed using the 6‐minute walk test in 12 patients with MS either before or during stimulation 18 .…”

“…[9][10][11][12] Beyond symptom management, tDCS has been theorized to be a neuromodulation tool that can induce long-term potentiation (LTP) phenomena causing specific changes in synaptic efficacy of the targeted brain region, 10,13,14 and promote synergistic effects when paired with a training activity. 15,16 Thus far, studies using tDCS over M1 have shown mixed results in the treatment of gait functions in patients with MS. [17][18][19][20][21][22] However, these studies have used tDCS in only one or a few sessions, where multiple repeated treatments are necessary for behavioral effects.…”