Does APT cycling reduce spasticity in people with Multiple Sclerosis
Research type
Research Study
Full title
Does a single session of cycling using lower limb active passive trainers reduce spasticity, as measured by the H-reflex, in people with moderate to severe Multiple Sclerosis ?
IRAS ID
255621
Contact name
Stuart Gray
Contact email
Duration of Study in the UK
0 years, 7 months, 28 days
Research summary
Summary of Research
Spasticity causes muscles to be stiff and difficult to move, and is a common problem in people with Multiple Sclerosis (pwMS). Studies have shown cycling can reduce leg spasticity in people with mild symptoms of MS, however few studies have included more disabled populations. Spasticity, and changes in spasticity over time, can be difficult to measure in clinical practise with commonly used measures lacking sensitivity. Neurophysiological tests can directly measure muscle activity or spasticity, and other studies have successfully used them to consider the effect of cycling in people with mild MS. However, there are few studies that have done so in a more disabled population or when using lower limb APTs. This study aims to determine whether a single session of APT cycling produces a reduction in leg spasticity by measuring H-reflex in a people with moderate to severe MS. It also aims to compare these measures to standard measures of spasticity.
We aim to recruit 30 pwMS from the Physically Disabled Rehabilitation Unit at the Queen Elizabeth University Hospital. Participants will complete a single session of APT cycling for 34 minutes (2 minutes warm up, 30 minutes active cycling, 2 minutes cool down). Spasticity will be assessed pre and post cycling. Participants will be included if they have a confirmed diagnosis of progressive MS, an EDSS of between 6.0 (requires a walking aid-cane, crutch etc-to walk about 100m with or without resting) and 8.5 (essentially restricted to bed much of day. Has some effective use of arms retains some self care functions) and spasticity in their lower limbs. Participants will be excluded if they have cognitive impairment (cannot understand instructions), other co-morbidities which would preclude them taking part in exercise or visual impairment (such that they cannot see the screen on the APT).Summary of Results
Does a single session of cycling using lower limb active passive trainers reduce spasticity, as measured by the H-reflex, in people with moderate to severe Multiple Sclerosis?Why was the research needed
Spasticity is one of the most troublesome symptoms affecting up to 85% of people with Multiple Sclerosis and occurs from a result of damage to the central nervous system. It is often described as muscle tension or stiffness. In some people spasticity can be helpful by masking lower limb weakness to create limb stiffness, which can allow functional transfers and walking. To others it can lead to reduced ability to perform self-care tasks, balance, walk and climb stairs, and is an area that patients often seek treatment for.A previous study undertaken by the researcher considered the effects of a four-week programme of lower limb APT cycling in people with moderate to severe Multiple Sclerosis. The study highlighted the need to identify a better, more sensitive measure of spasticity. The most common method of measuring spasticity is the Modified Ashworth Scale (MAS), a six-point scale that clinicians use to grade the resistance encountered during passive muscle stretching. Neurophysiology measures (Hoffmans reflex) have been used to assess spasticity in people with mild Multiple Sclerosis, however they have not been tried in people with moderate to severe Multiple Sclerosis.
What were the main questions studied
This is the first study to use the Hoffmans reflex, also known as the H-reflex, in people with moderate to severe MS whilst using lower limb Active Passive Trainers (APTs), which can assist with leg movement during cycling. The study had several aims. The first was to determine if spasticity, as measured by the H-reflex, was affected by a single session of cycling using the APT. The second was to consider if the H-reflex was a more sensitive measure of spasticity than the MAS and self-reported leg spasticity, measured using the Numerical Rating Scale (NRS). And lastly to help inform any future studies information was recorded on the number of people who met our criteria for inclusion in the study, the number who consented to participate and reasons for not, the ability to test the H-reflex and any adverse effects during the study and study completion rates.Who carried out the research (including details of sponsor, funding and any competing interests)
The research team consisted of a research physiotherapist and research assistant, both of whom were experienced neurological physiotherapists and had experience of treating people with MS. The study was funded by NHS Greater Glasgow and Clyde (NHSGGC) endowment fund and approved by both the West of Scotland Research Ethics Committee and NHSGGC research and development department.What treatments or interventions did the participants take/receive This study took place in the Neurorehabilitation Unit (NRU), Queen Elizabeth University Hospital, Glasgow and ran from 1st August 2021 to 30th April 2022. All participants taking part undertook a single session of lower limb APT cycling with outcome measures taken before and afterwards as detailed below.
Lower limb APT’s provide cycling from a seated or supine position with help, if required, of a motorised unit. The APT is on a moveable frame that can be positioned in front of a chair or bed and is adjustable in height. It also has footplates and calf supports with velcro straps to attach around both areas and features a display panel which is approximately 1.5 metres in front at eye level which provides feedback. The speed, resistance and type of exercise (active, active assisted or passive) can be adjusted depending on the participant.
During the study the participant was seated in a standard chair or their normal wheelchair which was positioned against the wall, and the APT positioned so that the participant was in a comfortable cycling position. The cycling session began with a two-minute warm up consisting of passive cycling, where the legs of the participant were moved by the APT at a speed of 10 revolutions per minute (rpm). The participant was then asked to cycle for 30 minutes which was then followed by two minutes of passive cycling as a cool down. If the participant was unable to actively cycle at any point during the 30-minute exercise period, or if they had a spasm, the APT reverted to the passive mode. Outcome measures were recorded immediately before the APT cycling and then following. On completion of the cycling session the H-reflex was measured again and where possible at 10, 20 and 30 minutes after completion of the cycling session.The primary outcome was spasticity and assessed using the H-reflex. The H-reflex is measured by electrical stimulation of a nerve and reflects the excitability of the nervous system. The H-reflex was recorded from the posterior tibial nerve, which is located at the back of the participant’s knee. After cleaning the skin with an alcohol wipe recording electrodes were applied. Stimulation was then adjusted until the correct nerve position was established, with twelve stimuli recorded and the data saved to enable analysis after the session.
The secondary measures of spasticity were the MAS and NRS. The MAS is a six-point scale (0-4) which grades the resistance encountered during passive muscle stretching. In this scale zero represents no increase in tone and four is graded where the affected part is rigid and unable to be moved. The NRS was used to measure self-reported leg stiffness, with 0 representing no leg stiffness/spasticity and 10 the worst possible leg stiffness/spasticity, or as bad as it could be. The participants were asked to give a verbal score of their leg stiffness/spasticity prior to and after completion of the APT cycling and H-reflex tests.What medical problems (adverse reactions) did the participants have? What happened during the study No adverse reactions or medical problems were noted during the study period.
What were the results of the study
During the study period 45 people with a diagnosis of MS were admitted to or attended NRU outpatient clinics. From this 34 people met the criteria used by the study and were invited to participate, with 16 declining for reasons such as fatigue, transport issues or due to work commitments. Eighteen participants were recruited to the study but two dropped out due to hospital admissions preventing their participation. It was also not possible to elicit the H-reflex in one participant and so the results are based on the 15 participants.All of the participants were able to complete the H-reflex testing before, after and 10-minutes after completion of the APT cycling session (n=15). This reduced by one at the 20-minute assessment (n=14) and by the final assessment 30 minutes after APT cycling only 11 participants were able to complete it. Reasons the participants gave for stopping testing included the need to use the bathroom (n=3) and being too uncomfortable from prolonged sitting (n=1).
The data recorded from the H-reflex tests was analysed at each time point, with the reliability of the data also considered during statistical analysis. The average H-reflex latency which is the time taken for the reflex to appear, was found to be consistent in 13 participants with two displaying a much shorter time. The average latency was found to be 31.4 ± 0.7ms. The overall average H-reflex amplitude, which describes the size of the reflex, was found to be 0.27 ± 0.02mV and was found to have increased at all time points following APT cycling. When considering the reliability of the data obtained, the H-reflex was found to be highly variable and only one participant showed good reliability across all of the tests.
Analysis of the other measures of spasticity showed little change. A slight reduction in the MAS was noted to the left calf and ankle muscle only and self-reported spasticity (NRS) was also found to show little change. Nine participants reported their leg stiffness to have reduce, four reported it to have increased and two felt no change. These changes were not found to be significant.Overall, the study did not find spasticity, as measured by the H-reflex, to be changed following 30 minutes of APT cycling in people with moderate to severe MS. Nor did the study show a change in self-reported spasticity or the MAS, however the participants were noted to have low levels of spasticity in both legs. And while the H-reflex was found to be safe and feasible to complete as no adverse effects were found during the study, the data obtained was found to be highly variable. The H-reflex was found to be time consuming and challenging to complete, and participant comfort was also identified as an issue during testing. The shortest session lasted 75 minutes while the longest took 150 minutes to complete. All of these factors were felt to have influenced the results of the study, and further research is needed to determine If the H-reflex is a more sensitive measure of spasticity than other measures.
How has this study helped patients and researchers?
This study was the first to consider the use of the neurophysiology (H-reflex) as a measure of spasticity in people with moderate to severe MS. In addition, the study involved people with higher levels of disability, a group frequently overlooked in research and thus has added to the evidence base. While the study was unable to determine if the H-reflex was a more sensitive way to measure of spasticity in people with moderate to severe MS, it did find the test to be feasible and safe. The data obtained from testing the H-reflex was highly variable and it was felt that several other factors influenced it such as the participant position, comfort and length of time required to complete the measures. The study was able to make several recommendations for future research. The use of an alternate chair such as a recliner chair could facilitate a more supportive and comfortable position for testing, which would also enable APT cycling. The number of assessments could also be reduced to improve the length of time required to complete the study and help improve the reliability of the data obtained. Lastly the study corroborates the ongoing challenge of accurately and reliably measuring spasticity. The MAS continues to be commonly used in practice and research, however lacks sensitivity and the study would also recommend clinicians stop using it and find an alternative measure instead.Details of any further research planned
At this time no further research is planned.Where can I learn more about this study?
This study was complete at part of a PhD thesis submitted to the University of Glasgow, and will be available to review online following completion. Future plans to disseminate the research include presentation of the results to the study participants and local clinicians and by publication of the study results.REC name
West of Scotland REC 3
REC reference
19/WS/0103
Date of REC Opinion
10 Sep 2019
REC opinion
Further Information Favourable Opinion