Effects of Robotic Exoskeleton-Aided Gait Training in the Strength, Body Balance, and Walking Speed in Individuals With Multiple Sclerosis: A Single-Group Preliminary Study

Abstract

Objective: To assess effects of 15 exoskeleton-assisted gait training sessions, reflected by the muscle strength of the lower limbs and by walking speed immediately after the training sessions and at the 6-week follow-up.

Design: Single-group longitudinal preliminary study.

Setting: Individuals with multiple sclerosis (MS) at a hospital neurology ward.

Participants: Participants (N=14) included women and men aged from 36-61 years, with Expanded Disability Status Scale scores from 5.0-6.5.

Interventions: Exoskeleton-assisted walk training.

Main outcome measures: Primary outcomes included dynamometric knee extensor and flexor strength (Biodex Pro4), postural balance, and center of pressure displacements (Zebris FMD-S). Secondary outcomes included walking speed measured with the timed 25-foot walk test and fatigue (Fatigue Severity Scale). Assessments were performed 4 times, that is, prior to the start of the program (T0), at the end of the physiotherapy without an exoskeleton (T1), at the end of the exoskeleton-assisted training (T2), and at 6-week follow-up (T3).

Results: At the end of exoskeleton-assisted gait training there was a statistically significant improvement in peak torque of knee extensor muscles compared with the period of exercise without an exoskeleton. No statistically significant change was identified in the value of peak torque of knee flexors at T1. Likewise, the assessment at T2 showed the change in peak torque of knee flexors was not significant. The participants presented significantly faster walking speed after exoskeleton-assisted gait training compared with T0 and T1. No improvement was found in body balance. The subjects reported lower fatigue after exoskeleton-assisted gait training; however, the differences between the assessments at T1 and T0 as well as at T2 and T1 were statistically insignificant.

Conclusions: Individuals with MS and severe gait impairment participating in exoskeleton-assisted gait training achieved significant improvement in lower-limb muscle strength and increase in walking speed, yet the effect was not long-lasting.

Keywords: Exoskeleton device; Gait; Multiple sclerosis; Muscle strength; Rehabilitation.