P 36 Split-belt training but not cerebellar anodal tDCS improves stability control and reduces risk of fall in patients with Multiple Sclerosis. (May 2022)

• Record Type: Journal Article
• Authors: Nguemeni, C.; Hiew, S.; Kögler, S.; Homola, G.; Volkmann, J.; Zeller, D.
• Is Part Of: Clinical neurophysiology. Volume 137(2022)
• Page Start: e35
• Page End: e36
• Publication Date: 2022-05
• Subjects: Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2022.01.067
• Languages: English
• ISSNs: 1388-2457

Abstract

Abstract : Introduction: Multiple Sclerosis (MS) is a chronic neurological disease leading to gait impairment in 40-60% of people with MS (PwMS). The following loss of mobility and increased risk of falls is a key concern due to the interference with activities of daily living and independence. Further, a heightened fear of falling constitutes a vicious cycle leading to deconditioning and social isolation. The management of motor symptoms in MS remains a therapeutic challenge. Therefore, it is of utmost importance to develop effective and alternative approaches to motor symptom management. Split-belt treadmill (SBT) paradigms are a promising tool for improving gait and balance in PwMS due to its ability to improve walking symmetry. Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulatory method that is emerging as a promising rehabilitative tool. Objective: We aimed to evaluate the therapeutic potential of a non-pharmacological intervention combining multiple sessions of SBT with cerebellar anodal tDCS (ca-tDCS) on gait and balance in PwMS. We hypothesized that the combination of motor training and stimulation would be complementary, further translating to a reduction in risk of falls and increased mobility in PwMS. Patients and Methods: 22 PwMS received six sessions of anodal (PwMSreal, n = 12) or sham (PwMSsham, n = 10) tDCS to the cerebellum ipsilateral to the faster leg prior to performing the locomotor adaptation task on the SBT. To evaluate the effect of the intervention on gait and balance, functional gait assessment (FGA) scores and distance walked in 2 minutes (2MWT) were measured at baseline (T0), day 6 (T5) and at 4-week follow up (T6). Results: PwMSreal and PwMSsham showed the same level of performance and changes on the motor outcomes independent from tDCS stimulation mode applied to the cerebellum (anodal vs. sham, p > 0.05 on FGA and 2MWT). When the data were pooled across the groups to investigate the effects of multiple sessions of SBT training alone, an improvement in FGA scores relative to baseline by 3.3 and 5.1 points at T5 and T6 respectively was found (p < 0.001). The change in FGA at T6 was significantly higher than at T5 ( p = 0.010) underlining a long-lasting improvement. An improvement in distance walked during the 2MWT was also observed by 12.31 m on T5 and 11.56 m T6 relative to T0 (p < 0.050) . Conclusion: While no effect of ca-tDCS was found on improving gait and balance in PwMS, multiple sessions of SBT walking resulted in a significant and lasting improvement in gait stability and endurance as measured by FGA and 2MWT respectively. Before we can rule out any potential beneficial effect of combining tDCS with training, more thorough investigations into altered brain activation and functional connectivity patterns in PwMS are needed which could aid the selection of more effective tDCS parameters that will be able to boost therapeutic outcomes.