Gait kinematics of people with multiple sclerosis and the acute application of functional electrical stimulation

Abstract

This study aimed to (i) compare the gait characteristics of people with Multiple Sclerosis (pwMS) to those of healthy controls walking at the same average speed, and (ii) assess the effects of the acute application of Functional Electrical Stimulation (FES) to the dorsiflexors. Twenty-two people with pwMS (mean age 49 years), prescribed FES, and 11 age matched healthy controls participated. Three dimensional gait kinematics were assessed whilst (i) pwMS and healthy controls walked at self-selected speeds (SSWS), (ii) healthy controls also walked at the average walking speed of the pwMS group, and (iii) people with MS walked using FES. Compared to healthy controls walking at their SSWS, pwMS walked slower and showed differences in nearly all gait characteristics (p<0.001). Compared to healthy controls walking at the same average speed, pwMS still exhibited significantly shorter stride length (p=0.007), reduced dorsiflexion at initial contact (p=0.002), reduced plantar flexion at terminal stance (p=0.008) and reduced knee flexion in swing (p=0.002). However, no significant differences were seen between groups in double support duration (p=0.617), or hip range of motion (p=0.291). Acute application of FES resulted in a shift towards more normal gait characteristics, except for plantar flexion at terminal stance which decreased. In conclusion, compared to healthy controls, pwMS exhibit impairment of several characteristics that appear to be independent of the slower walking speed of pwMS. The acute application of FES improved most impaired gait kinematics. A speed matched control group is warranted in future studies of gait kinematics of pwMS.

Keywords: 3D gait analysis; Functional Electrical Stimulation; Multiple Sclerosis; Walking speed.