Testing electrical stimulation during early rehabilitation to manage phantom limb pain and improve walking after below-knee amputation
| ISRCTN | ISRCTN13542181 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN13542181 |
| Integrated Research Application System (IRAS) | 370690 |
| Medical Research Council grant reference | MR/X502996/1 |
| Sponsor reference | RG_26-079 |
| Sponsor | University of Birmingham |
| Funder | Medical Research Council |
- Submission date
- 10/11/2026
- Registration date
- 12/11/2026
- Last edited
- 11/11/2026
- Recruitment status
- Not yet recruiting
- Overall study status
- Ongoing
- Condition category
- Nervous System Diseases
Plain English summary of protocol
Background and study aims
People who have had a below-knee amputation may experience phantom limb pain, which is pain that feels as though it comes from the missing part of the leg. This pain can affect sleep, daily activities, walking and quality of life.
Functional electrical stimulation (FES) uses small electrical pulses applied through pads placed on the skin to activate muscles. Previous research suggests that using FES during walking may help reduce phantom limb pain and improve walking ability.
The Early MoFit study aims to find out whether FES can be used safely, comfortably and practically during the early stages of rehabilitation after below-knee amputation. The study will also explore whether FES may help reduce phantom limb pain and improve walking and quality of life.
Who can participate?
Adults aged 18–80 years who have had a below-knee amputation on one side within the past two years, have been using a prosthetic leg for less than one year, and currently experience phantom limb pain. Participants must be able to walk using their prosthetic leg, with or without a walking aid, and safely complete the study assessments.
What does the study involve?
Participants will be randomly assigned to start with either six weeks of FES-assisted walking or six weeks of walking without FES. After a six-week break, participants will switch to the other condition. Everyone will therefore experience both conditions.
During the FES period, participants will use a portable electrical stimulation device while walking for at least 20 minutes per day, where safe and comfortable. During the non-FES period, participants will continue their usual walking activities and wear a physical activity monitor.
Participants will complete a short daily pain diary and receive regular telephone calls from the research team.
Assessments will take place before treatment starts and at Weeks 6, 12 and 18. These will include questionnaires about pain and quality of life and short walking assessments using wearable movement sensors. A final telephone follow-up will take place at Week 21.
Each participant will take part for approximately 21 weeks, including the final follow-up.
What are the possible benefits and risks of participating?
Participants may experience improvements in phantom limb pain or walking ability, although these benefits cannot be guaranteed.
FES may cause temporary skin irritation, muscle soreness, fatigue or discomfort during stimulation. The research team will provide training and monitor participants' safety throughout the study.
The findings will help researchers understand whether FES is suitable for use during early rehabilitation and inform the design of a larger clinical trial.
Where is the study run from?
The study is sponsored by the University of Birmingham and will recruit participants from the West Midlands Rehabilitation Centre in Birmingham and Livewell Southwest in Plymouth, United Kingdom.
When is the study starting and how long is it expected to run for?
January 2027 to September 2027.
Who is funding the study?
The study is funded by the Medical Research Council Impact Acceleration Account (MRC IAA), UK.
Who is the main contact?
Dr Ziyun Ding, University of Birmingham, z.ding@bham.ac.uk
Contact information
Public, Scientific
School of Engineering, University of Birmingham, Edgbaston
Birmingham
B15 2TT
United Kingdom
| Phone | +44 121 414 4159 |
|---|---|
| j.m.kim@bham.ac.uk |
Principal investigator
School of Engineering, University of Birmingham, Edgbaston
Birmingham
B15 2TT
United Kingdom
| Phone | +44 121 414 4159 |
|---|---|
| z.ding@bham.ac.uk |
Study information
| Primary study design | Interventional |
|---|---|
| Allocation | Randomized controlled trial |
| Masking | Open (masking not used) |
| Control | Active |
| Assignment | Crossover |
| Purpose | Treatment |
| Scientific title | Early intervention with model-driven FES to manage post-amputation phantom limb pain and optimise gait (Early MoFit): a feasibility randomised trial |
| Study acronym | Early MoFit |
| Study objectives | The primary objective of this study is to evaluate the feasibility, safety, acceptability, and practical delivery of model-driven functional electrical stimulation (FES) during early prosthetic rehabilitation following unilateral transtibial amputation. The secondary objectives are to obtain preliminary estimates of the effects of FES-assisted walking on phantom limb pain severity, pain interference, walking performance, daily physical activity, and health-related quality of life. The study will also assess recruitment, retention, adherence, intervention usability, and participant and clinician experiences. The findings will inform refinement of the intervention protocol and the design of a future definitive randomised controlled trial. |
| Ethics approval(s) |
Approved 10/11/2026, Wales Research Ethics Committee 4 (Health and Care Research Wales, Floor 4, Crown Building, Cathays Park, Cardiff, CF10 3NQ, United Kingdom; +44 29 2023 0457; Wales.REC4@wales.nhs.uk), ref: 26/WA/0286 |
| Health condition(s) or problem(s) studied | Phantom limb pain following unilateral transtibial (below-knee) amputation during early prosthetic rehabilitation. |
| Intervention | This study is a multicentre, randomised, two-period crossover feasibility trial involving eight participants with unilateral transtibial amputation during early prosthetic rehabilitation. Following screening and baseline assessments, participants will be randomised to one of two treatment sequences: Group A: Six weeks of functional electrical stimulation (FES)-assisted walking, followed by a six-week washout period and six weeks of walking without FES. Group B: Six weeks of walking without FES, followed by a six-week washout period and six weeks of FES-assisted walking. FES intervention: Participants will receive model-driven FES using the ODFS Pace XL device (Odstock Medical Limited, UK). Electrical stimulation will be delivered to the residual vastus muscle group during the stance phase of walking, synchronised with gait events using a footswitch positioned beneath the insole of the prosthetic footwear. A trained FES clinician will fit and configure the device, adjust stimulation parameters according to individual needs and comfort, and provide training for safe use. Participants will be instructed to undertake FES-assisted walking for at least 20 minutes per day over six weeks, where safe and tolerated. Non-FES condition: Participants will continue their usual walking activities without electrical stimulation while wearing a physical activity monitor. Washout period: A six-week washout period will separate the two treatment conditions. No FES treatment will be provided during this period. Monitoring and follow-up: Participants will complete daily pain diaries throughout the study and receive weekly telephone reviews during both treatment periods to monitor adherence, symptoms, device use and adverse events. Outcome assessments will be conducted at baseline and Weeks 6, 12 and 18. A final follow-up telephone call will take place at Week 21 to assess health status, delayed adverse events and participant experiences. |
| Intervention type | Device |
| Phase | Not Applicable |
| Drug / device / biological / vaccine name(s) | ODFS Pace XL Functional Electrical Stimulation (FES) device |
| Primary outcome measure(s) |
|
| Key secondary outcome measure(s) |
|
| Completion date | 30/09/2027 |
Eligibility
| Participant type(s) | |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 80 Years |
| Sex | All |
| Target sample size at registration | 8 |
| Key inclusion criteria | 1. Adults aged 18–80 years who are able to provide written informed consent 2. Unilateral transtibial (below-knee) amputation within the past two years 3. Fitted with and using a prosthesis for less than one year 4. Current phantom limb pain with a severity of at least 3/10 on a numerical rating scale (NRS) 5. Able to walk with a prosthesis, with or without an additional walking aid 6. Able to safely complete the study walking assessments, as judged by the clinical team 7. Willing and able to comply with study procedures, including use of the FES device or activity monitor, daily pain diary, study visits, and telephone reviews |
| Key exclusion criteria | 1. Contraindications to functional electrical stimulation (FES), including cardiac pacemakers, implanted defibrillators, other implanted electronic devices, uncontrolled epilepsy, or other conditions considered unsuitable for FES by the clinical team 2. Pregnancy, planned pregnancy during the study, or current breastfeeding 3. Skin conditions, wounds, infections, marked skin sensitivity, or other local issues preventing safe electrode placement on the residual limb 4. Significant medical, neurological, cardiovascular, musculoskeletal, or other conditions that may affect safe participation 5. Inability to safely complete the study walking assessments using the usual prosthesis and walking aid, where required 6. Severe cognitive impairment or other conditions affecting the ability to provide informed consent or follow study instructions 7. Insufficient English language ability to provide informed consent and complete study procedures 8. Current participation in another interventional research study that may affect the study outcomes 9. Any other condition that, in the opinion of the clinical team, makes participation unsafe or inappropriate |
| Date of first enrolment | 04/01/2027 |
| Date of final enrolment | 31/03/2027 |
Locations
Countries of recruitment
- United Kingdom
- England
Study participating centres
Selly Oak
Birmingham
B29 6JA
England
200 Mount Gould Road
Plymouth
PL4 7PY
England
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan | Anonymised individual participant data supporting published findings may be made available to other researchers upon reasonable request, subject to participant consent, approval by the Chief Investigator and Sponsor, and applicable data protection regulations. Any data shared will be fully anonymised to ensure that individual participants cannot be identified. Requests for data access will be reviewed in accordance with the University of Birmingham's data-sharing procedures and relevant ethical and regulatory requirements (https://intranet.birmingham.ac.uk/student/libraries/research/rdm/index.aspx). |
Editorial Notes
11/11/2026: Study's existence confirmed by the Health Research Authority (HRA) (UK).
