A comparison of the initial orthotic effects of functional electrical stimulation and ankle-foot orthoses on the speed and oxygen cost of gait in multiple sclerosis.

Background: Foot drop affects walking in people with multiple sclerosis (pwMS). This study compares the initial orthotic effects of two treatments for foot drop: ankle-foot orthoses (AFO) and functional electrical stimulation (FES), on the speed and oxygen cost of walking in MS.

Method And Materials: Seventy-eight pwMS were randomised to receive AFO or FES (ODFS PACE (OML, Salisbury, UK)). Participants completed the 25-ft walk test (25ftWT) and 5-min self-selected walk test (5minSSWT), from which oxygen cost was determined, with and without their device. Between-, within- and sub-group analyses (based on baseline walking speed of <0.8 m/s (slow) or ≥0.8 m/s (fast)) were undertaken.

Results: No significant differences between baseline measures were observed. The AFO group walked significantly slower than the FES group (5minSSWT,  = 0.037, 0.11 m/s). The AFO group walked significantly slower with than without AFO (25ftWT,  = 0.037), particularly in the fast-walking group (  = 0.011). The slow-walking FES group walked significantly faster with FES than without (25ftWT;  = 0.029, 5minSSWT;  = 0.037). There were no differences in the fast-walking FES group or in the oxygen cost for either device.

Conclusion: AFO reduced walking speed, particularly in fast walkers. FES increased walking speed in slow, but not fast walkers.