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

Abstract

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, p = 0.037, 0.11 m/s). The AFO group walked significantly slower with than without AFO (25ftWT, p = 0.037), particularly in the fast-walking group ( p = 0.011). The slow-walking FES group walked significantly faster with FES than without (25ftWT; p = 0.029, 5minSSWT; p = 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.

The Relationship Between Walking Speed and the Energetic Cost of Walking in Persons With Multiple Sclerosis and Healthy Controls: A Systematic Review

“…Results of overground and treadmill walking studies are presented in Figure 2c and Figure 2d, respectively. The range in walking speeds in overground conditions 28,30,39,41,[43][44][45][46][47][48][49][50][51][52][53][54][55] was lower, compared with treadmill walking, [33][34][35]56 with speeds between 0.43 and 1.48 m/s with Cw values between 0.16 and 0.44 mL O 2 /kg/m. The majority of the treadmill speeds were set at a predetermined velocity, ranging from 0.28 to 1.79 m/s, with concurring Cw values from 0.14 to 0.44 mL O 2 / kg/m.…”

“…After full text screening, 25 studies were excluded according different criteria. Additionally, 4 studies were excluded due to use of apparent overlapping datasets, [26][27][28][29] leaving a remaining 29 studies for analysis describing the Cw at different speeds in pwMS and pwMS and healthy subjects. Eight studies included healthy subjects, 19 studies were included for overground walking, and 10 studies were included for treadmill walking.…”

“…Specifically, the items on sample size calculation including power description, variance, and effect estimates was often not reported, except for 2 studies. 28,45 Both the expected and measured power of a certain outcome would improve transparency of the study results. In addition, the item on blinding was not reported correctly in most studies.…”

Functional electrical stimulation for foot drop in people with multiple sclerosis: The relevance and importance of addressing quality of movement

“…Thirty-five articles meeting the search criteria were identified, 19 of these were assessed for inclusion eligibility and 9 were included in the analysis. 10,11,13–19 Eligible papers were scrutinised and participant characteristics, methods of data collection and analysis and major findings of each paper were extracted (A.D.S., T.P.). A critical interpretive synthesis of the literature and analysis of the evidence was undertaken 20 (A.D.S., T.P., R.J., T.B., K.R.…”

“…3 FES use in MS is usually delivered through surface adherent electrodes although implanted systems are also available, but are used rarely in MS due to possible implantation risks. 8 FES, seen as an alternative, has a comparable or better orthotic effect 7,9,10 generating active rather than passive movement but is in limited use despite users reporting significantly reduced perception of exertion on walking and many choosing FES as a preferred option compared to AFOs. 11…”