The effect of functional electrical stimulation on the physiological cost of gait in people with multiple sclerosis

Functional electrical stimulation (FES) is used clinically in the management of drop foot in people suffering from neurological conditions. The aim of the study was to investigate the effects of FES, in terms of speed and physiological cost of gait, in people with multiple sclerosis (pwMS).

Twelve pwMS and 12 healthy matched controls walked at their own preferred walking speed (PWS) for 5 min around a 10 m elliptical course. Subjects with MS completed the protocol with and without using their FES. In addition, control subjects completed the protocol twice more walking at the same PWS of the pwMS to which they were matched.

Wearing FES lead to a significant improvement in walking speed (0.49 ms(-1) and 0.43 ms(-1) with and without their FES respectively; P<0.001) and a significant reduction in the physiological cost of gait (0.41 mL min(-1) kg(-1) m(-1) and 0.46 mL min(-1) kg(-1) m(-1) with and without FES respectively; P=0.017) in pwMS. The speed of walking, oxygen uptake, and physiological cost were significantly different between pwMS and controls both at preferred and matched speeds. Although pwMS exhibit a higher physiological cost of walking, FES offers an orthotic benefit to pwMS and should be considered as a possible treatment option.