Experiences of functional electrical stimulation (FES) and ankle foot orthoses (AFOs) for foot-drop in people with multiple sclerosis.

PURPOSE: A constructivist phenomenological study explored impacts of ankle foot orthoses (AFOs) or functional electrical stimulation (FES) on people with foot-drop from multiple sclerosis (MS). METHOD: Focus groups following topic guides were analysed using interpretative phenomenological analysis, with researcher reflexivity, participant verification and peer checking of analysis. Participants with sustained use of the devices (under 2 y) were invited from two quantitative studies that (a) investigated immediate FES effects (n = 12) and (b) compared habitual use of AFO (n = 7) or FES (n = 6). Two focus groups addressed AFO (n = 4) and FES (n = 6) experiences. RESULTS: Similar numbers of positive and negative aspects were described for AFO and FES. Both reduced fatigue, improved gait, reduced trips and falls, increased participation, and increased confidence; greater balance/stability was reported for AFOs, and increased walking distance, fitness and physical activity for FES. Barriers to both included avoiding reliance on devices and implications for shoes and clothing; a non-normal gait pattern was reported for AFO, and difficulties of application and limitations in the design of FES. However, participants felt the positives outweighed the negatives. CONCLUSIONS: Participants felt benefits outweighed the drawbacks for AFO and FES; greater understanding of user preferences and satisfaction may increase likelihood of usage and efficacy. Implications for Rehabilitation Interventions to reduce the impacts of foot-drop in people with multiple sclerosis (MS) are important to optimise physical activity participation and participation in life; they include ankle foot orthoses (AFOs) and functional electrical stimulation (FES). Research is lacking regarding user satisfaction and perceived outcomes, therefore, two separate focus groups were conducted from a constructivist phenomenological perspective to explore the impacts of AFOs (n = 4) and FES (n = 6) on people with foot-drop from MS. Some similar positive aspects of AFO and FES use were described, including reduced fatigue, improved gait and fewer trips and falls, while common barriers included finding the device cumbersome, uncomfortable, and inconvenient, with some psychological barriers to their use. On balance, the impacts of the devices on improving activities and participation were more important for participants than practical barriers, highlighting the importance of combining understanding of individual experiences and preferences with clinical decision-making when prescribing a device to manage foot-drop.

Gait kinematics of people with multiple sclerosis and the acute application of functional electrical stimulation.

This study aimed to (i) compare the gait characteristics of people with Multiple Sclerosis (pwMS) to those of healthy controls walking at the same average speed, and (ii) assess the effects of the acute application of Functional Electrical Stimulation (FES) to the dorsiflexors. Twenty-two people with pwMS (mean age 49 years), prescribed FES, and 11 age matched healthy controls participated. Three dimensional gait kinematics were assessed whilst (i) pwMS and healthy controls walked at self-selected speeds (SSWS), (ii) healthy controls also walked at the average walking speed of the pwMS group, and (iii) people with MS walked using FES. Compared to healthy controls walking at their SSWS, pwMS walked slower and showed differences in nearly all gait characteristics (p<0.001). Compared to healthy controls walking at the same average speed, pwMS still exhibited significantly shorter stride length (p=0.007), reduced dorsiflexion at initial contact (p=0.002), reduced plantar flexion at terminal stance (p=0.008) and reduced knee flexion in swing (p=0.002). However, no significant differences were seen between groups in double support duration (p=0.617), or hip range of motion (p=0.291). Acute application of FES resulted in a shift towards more normal gait characteristics, except for plantar flexion at terminal stance which decreased. In conclusion, compared to healthy controls, pwMS exhibit impairment of several characteristics that appear to be independent of the slower walking speed of pwMS. The acute application of FES improved most impaired gait kinematics. A speed matched control group is warranted in future studies of gait kinematics of pwMS.

Quantification of gait kinematics and walking ability of people with multiple sclerosis who are new users of functional electrical stimulation.

OBJECTIVE: To assess whether the application of Functional Electrical Stimulation improves gait kinematics and walking ability in people with multiple sclerosis who experience foot drop. DESIGN: Acute open labelled comparative observation trial. PARTICIPANTS: Twelve people (3 females, 9 males, EDSS 2-4) with relapsing remitting multiple sclerosis (47.8 years (standard deviation 6.6)) who were new users of functional electrical stimulation. METHODS: Gait kinematics were recorded using 3D gait analysis. Walking ability was assessed through the 10-m walk test and the 6-min walk test. All assessments were performed with and without the assistance of functional electrical stimulation. The effect of functional electrical stimulation was analysed using paired t-tests. RESULTS: Ankle dorsiflexion at initial contact (p = 0.026), knee flexion at initial contact (p = 0.044) and peak knee flexion during swing (p = 0.011) were significantly greater whilst walking with Functional Electrical Stimulation. The increased peak dorsiflexion in swing of nearly 4 degrees during functional electrical stimulation assisted walking approached significance (p = 0.069). The 10-m walk time was significantly improved by functional electrical stimulation (p = 0.004) but the 6 min walk test was not. CONCLUSION: The acute application of functional electrical stimulation resulted in an orthotic effect through a change in ankle and knee kinematics and increased walking speed over a short distance in people with multiple sclerosis who experience foot drop.

Surface EMG characteristics of people with multiple sclerosis during static contractions of the knee extensors.

OBJECTIVES: This study was designed to determine whether any alterations existed in surface electromyography (sEMG) in people with multiple sclerosis (MS) during isometric contractions of the knee extensors. METHODS: Fifteen people with MS and 14 matched controls (mean ± SD age and body mass index 53·7 ± 10·5 versus 54·6 ± 9·6 years and 27·7 ± 6·1 versus 26·5 ± 4, respectively) completed 20%, 40%, 60% and 80% of their maximal voluntary contraction (MVC) of the knee extensors. sEMG was recorded from the vastus lateralis where muscle fibre conduction velocity (MFCV) and sEMG amplitude (RMS) were assessed. Body composition was determined using dual-energy X-ray absorptiometry and physical activity with the use of accelerometry. RESULTS: People with MS showed significantly (P<0·05) faster MFCV during MVC (6·6 ± 2·7 versus 4·7 ± 1·4 m s(-1) ) and all submaximal contractions, while RMS was significantly (P<0·05) less (0·11 ± 0·03 versus 0·24 ± 0·06 mV) in comparison with the controls. MVC along with specific thigh lean mass to torque, rate of force development and mean physical activity were significantly (P<0·01) less in PwMS. CONCLUSION: People with MS have elevated MFCV alongside reduced RMS during isometric contraction. This elevation in MFCV should be accounted for when interpreting sEMG from people with MS.