Evaluating the ability to recover finger extension with a wearable treatment ('PowerBead')
| ISRCTN | ISRCTN65503890 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN65503890 |
| National Institute for Health and Care Research (NIHR) | 208959 |
| Sponsor | University College London |
| Funder | National Institute for Health and Care Research |
- Submission date
- 23/11/2025
- Registration date
- 24/11/2025
- Last edited
- 24/11/2025
- Recruitment status
- Recruiting
- Overall study status
- Ongoing
- Condition category
- Nervous System Diseases
Plain English summary of protocol
Background and study aims
This study is looking at a new wearable device designed to help people who have had a stroke and now find it very hard to move their fingers. Around 32,000 people in the UK each year are affected in this way. The device gives two gentle signals: a small tap on the forearm and a click sound in one ear. Researchers want to see if using this device can help the brain and nerves relearn movement, making finger extension easier. The study will also check if the device is safe and easy to use at home in the future.
Who can participate?
-Healthy volunteers aged 18–75, with normal or corrected vision, and fluent in English.
-Stroke survivors aged 18–75, fluent in English, with normal or corrected vision, who had a stroke more than six months ago, are no longer receiving NHS support, and have moderate arm function based on a standard assessment.
What does the study involve?
Participants will wear the device during a single session lasting about four hours. The device will give gentle taps and clicks as part of the stimulation process. Researchers will measure changes in muscle activity and hand function before and after the session. Participants will also be asked for feedback about how easy the device is to use.
What are the possible benefits and risks of participating?
The device may help improve hand movement, but this cannot be guaranteed. The main risk is mild discomfort from wearing the device or from the tests, but these will be monitored closely. There is no surgery or invasive procedure involved.
Where is the study run from?
University College London (UK).
When is the study starting and how long is it expected to run for?
The study will start in August 2025 and is expected to finish in February 2026.
Who is funding the study?
The study is funded by the National Institute for Health and Care Research (NIHR) in the UK.
Who is the main contact?
Dr Laura Salisbury, laura@knitregen.com
Contact information
Public, Scientific, Principal investigator
33 Queen Square
London
WC1N 3BG
United Kingdom
| Phone | +44 7714464504 |
|---|---|
| laura@knitregen.com |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Single-centre interventional non randomized controlled study |
| Secondary study design | Non randomised study |
| Scientific title | Evaluating reticulospinal plasticity in neural circuits from a novel wearable treatment (‘PowerBead’) as a potential method for regaining finger extension post-stroke. |
| Study acronym | PowerBead |
| Study objectives | 1. Understand if RST and CST connectivity are strengthened after device use, evaluating LLSR, StartReact, AP/PA TMS and muscle response to TMS, compared before and after device usage 2. Detect changes in hand function, evaluate finger strength and individuation using a 5 digit force transducer 3. Evaluate device useability via participant feedback 4. Optimise device, participant inclusion criteria thereafter |
| Ethics approval(s) |
Approved 17/06/2025, UCL Ethics Committee (Academic Services, University College London, Gower Street, London, WC1E 6BT, United Kingdom; +44 203 108 8216; ethics@ucl.ac.uk), ref: 1378 |
| Health condition(s) or problem(s) studied | Recovery of finger extension post-stroke with survivors who are moderately to severely impaired |
| Intervention | Participants are randomized into a single-arm intervention study to receive the wearable device delivering non-invasive dual stimuli. The device delivers a two-step stimulation: a mechanical tap that activates the extensor digitorum muscle in the arm, followed by an auditory click delivered through a single earphone on the contralateral side of the body. Each treatment session consists of a four-hour stimulation cycle. The intervention is administered according to the device’s standard operating procedures, and no placebo or sham control is included in the study. Participants receive a single treatment with monitoring for adherence and safety throughout the intervention period. |
| Intervention type | Device |
| Phase | Phase I |
| Drug / device / biological / vaccine name(s) | PowerBead |
| Primary outcome measure(s) |
Increased reticulospinal drive associated with startle reflex activation measured using custom StartReact code via EMG before and after the administration of the PowerBead treatment. |
| Key secondary outcome measure(s) |
1. Neurostimulation data measured using AP/PA TMS with and without startle, before and after the administration of the PowerBead treatment. |
| Completion date | 28/02/2026 |
Eligibility
| Participant type(s) | Healthy volunteer, Patient |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 75 Years |
| Sex | All |
| Target sample size at registration | 40 |
| Key inclusion criteria | For healthy volunteers: 1. Fluent in English and able to understand the protocol and provide informed consent; 2. Aged between 18 to 75 years old; 3. Normal vision or corrected vision (using contact lenses or glasses if needed); For stroke participants: 1. Fluent in English and able to understand the protocol and provide informed consent; 2. Aged between 18 to 75 years old; 3. Normal vision or corrected vision (using contact lenses or glasses if needed); 4. >6 months post-stroke; 5. Discharged from NHS support; 6. Fugl Meyer Assessment - Upper Extremity (FMAUE) scores between 23- 52 divided into three groups: (a)poor, (b)limited and (c)notable functional capacity). |
| Key exclusion criteria | For healthy volunteers: 1. Are pregnant or possibly pregnant; 2. Have metal in the brain, skull or forearm; 3. Have any infectious diseases; 4. Have issues with dermatitis or sensitive skin; 5. Clinical history/ diagnosis of neurological, musculoskeletal, or mental disorders (including stroke); 6. Have a pacemaker; 7. Have any disorders relating to blood clotting or wound healing; 8. Have tinnitus or other hearing ailments; 9. Have a clinical history or diagnosis of epilepsy, cerebrovascular disease, dementia or increased intracranial pressure; 10. Have a history of repetitive or severe head trauma; 11. Have any primary or secondary tumours in the CNS. For stroke participants: 1. Are pregnant or possibly pregnant; 2. Have metal in the brain, skull or forearm; 3. Have any infectious diseases; 4. Have issues with dermatitis or sensitive skin; 5. Clinical history/ diagnosis of neurological, musculoskeletal, or mental disorders (other than stroke); 6. Have a pacemaker; 7. Have any disorders relating to blood clotting or wound healing; 8. Have any lesions to the brain stem as a result of the stroke(s); 9. Have tinnitus or other hearing ailments; 10. Have a clinical history or diagnosis of epilepsy, cerebrovascular disease, dementia or increased intracranial pressure; 11. Have a history of repetitive or severe head trauma; 12. Have any primary or secondary tumours in the CNS. |
| Date of first enrolment | 08/08/2025 |
| Date of final enrolment | 31/01/2026 |
Locations
Countries of recruitment
- United Kingdom
- England
Study participating centre
London
WC1N 3BG
England
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Available on request |
| IPD sharing plan | The datasets generated during and/or analysed during the current study will be available upon request from Dr Laura Salisbury at: laura@knitregen.com Data that will be shared includes: - Participant characteristics: Age, self-identified gender, height, weight, BMI, subcutaneous fat levels in the forearm, date of stroke onset, type of stroke, impairment level (FMUEA score). - Neurostimulation data: AP/PA TMS with and without startle, StartReact - Participant’s behaviour: Force data captured from a bespoke finger individuation device using force transducers to measure finger extension. - Electrophysiology data: EMG data recording muscle activity. Data will be available once the study has concluded, by request for up to 10 years. Data will be shared with parties who have no conflict of interest to the research. Consent from participants was obtained in all cases prior to data collection. Data will be anonymised and therefore not personally identifiable. Anonymised data will be stored by UCL for 10 years post project completion in accordance with UCL Records Management Policy. |
Editorial Notes
24/11/2025: Trial's existence confirmed by UCL Ethics Committee.
