Changes in foot clearance patterns with functional electrical stimulation (FES) and ankle foot orthosis (AFO) in the presence of foot drop post-stroke

Abstract

Introduction: Foot drop post-stroke is a significant precursor to falls to which is a substantial influencer in the quality of life. This study set out to compare any immediate changes in spatiotemporal and kinematic foot clearance patterns that occur with the use of Functional Electrical Stimulation (FES) and Ankle Foot Orthosis (AFO) in the presence of foot drop post-stroke. Methodology and design: This research adopted a case study research design. A patient, who experienced a stroke was chosen and monitored at a self-selected walking speed with a motion capture system using a Helen Hayes marker set-up without any aid, with an AFO and with FES (Bioness® L300) in the same session respectively, wearing own footwear. A Timed Up and Go (TUG) test was carried out to assess the risk of falls in all the three walking trials. Data Analysis: The analysis was carried out by recording spatiotemporal values for the whole gait cycle, and kinematic data measured throughout the whole gait cycle and peak angles where interpreted for the three modalities under assessment. Recording of the TUG test after every successful set of walks in seconds for every modality was carried out, and data was then extrapolated in MS Excel™ for analysis and compared in a same subject design method. Results/conclusion: The results obtained showed inconclusive spatiotemporal values with minimal difference between AFO and FES modalities, such as 95.0 ± 2.25 steps/min to 97.6 ± 4.30 steps/min for cadence and 0.66 ± 0.051 m/s to 0.62 ± 0.032 m/s for walking speed respectively. Although FES provided less variation in movements (0.75SD) as opposed to AFO (1.2SD) and cleared the foot further off the ground by improving dorsiflexion by 2.8°, the risk of falls as interpreted by the TUG criteria increased as the results where poorer than AFO by 1.05 seconds.