Multiple Sclerosis (MS) has an estimated prevalence of 337-362 per 100,000 people and is characterized as an autoimmune disease that causes axonal degradation, leading to mobility and cognitive impairments. While physical rehabilitation has been identified as one of the best methods for restoring function in MS, it can be challenging to implement in individuals with severe impaired mobility. One approach is the use of a novel assistive device such as a wearable Robotic exoskeletons (RE). REs have been increasingly used to provide gait rehabilitation for persons with mobility disorders (e.g. spinal cord injury and stroke) [3-7], and more recently for persons with MS[8, 9]. The current study examines potential improvements in mobility, cognitive processing speed, as well as resting-state (RS) functional connectivity of the brain in persons with MS through the use of RE.
To determine if gait training using RE improves mobility, cognition, and brain RS functional connectivity in persons with MS.
Four persons with relapsing-remitting MS (RRMS) participated in this randomized pilot prospective study. Two MS patients received eight 1-hour RE training sessions (Ekso-GT, Ekso Bionics, Berkley, CA, USA) administered by a licensed physical therapist; the other two participants received eight 1-hour Conventional Gait Therapy (CGT) sessions. The 8-seesion interventions occurred over a four week period (2 sessions/week). The Six Minute Walk Test (6MWT), Symbol Digit Modalities Test (SDMT), and RS functional MRI (fMRI) of the brain, acquired using a Siemens Skyra 3 Tesla MRI scanner were assessed at baseline and after the 4-week intervention. A seed-based RS functional connectivity analysis approach was used, with seeds placed in the motor and ventromedial prefrontal cortices (vmPFC).
The RE group improved by 21% in walking distance in the 6MWT while the CGT group showed essentially no change (a 2% decrease in the distance). The RE group also showed improvements in SDMT performance (ZRE = 0.95; ZCGT = - 0.78), as well as improvements in functional connectivity in the motor cortex (ZRE = 0.8; ZCGT = - 0.08) and in the vmPFC (ZRE = 0.8; ZCGT = -0.003).
Improvements in mobility, cognitive processing speed, and resting state functional connectivity in the motor cortex and in the vmPFC were observed for participants in the RE gait training group but not in the CGT group. These pilot results suggest that gait training using RE can be an effective therapy for improving walking ability, cognitive function, and brain connectivity in resting-state networks in persons with MS. Data analysis of a larger sample is underway to confirm the findings.