Five-Year Follow-up of a Longitudinal Cohort Study of the Effectiveness of Functional Electrical Stimulation for People with Multiple Sclerosis.

Background: Few studies have examined the long-term consequences of using peroneal nerve functional electrical stimulation (FES) for people with multiple sclerosis (MS). This study examines orthotic effects on a longitudinal cohort and explores additional benefits of FES on self-reported measures such as joint pain.

Methods: One hundred forty-five people with foot drop and MS were included (mean age, 52 [range, 28-74] years). Orthotic effects, unassisted walking speed, and clinically important differences (ie, ≥0.05 and ≥0.10 m/s) were derived from walking speed over 10 m. Visual analogue scales examined joint pain, walking effort, trips, confidence, and quality of life. Measures were taken on day 1, after 6 months, and at 2, 3, 4, and 5 years.

Results: A significant difference was found overall for walking with FES compared with walking without FES for the 5-year period (P < .001). Despite a significant decline in overall unassisted walking speed at baseline (0.58 m/s) compared with 5 years later (0.46 m/s) (P < .001), participants achieved an orthotic effect with (0.52 m/s) versus without (0.46 m/s) FES after 5 years (P < .001). A significant decrease in joint pain was found after 6 months compared with day 1 (P = .004), which was maintained after 5 years (P < .001).

Conclusions: Despite progression of MS, long-term users of FES still benefit from an orthotic effect after using FES for 5 years. The study highlights the need for further work to assess the perceived benefits of FES regarding the experience of joint pain.