Condition category
Musculoskeletal Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status

Plain English Summary

Background and study aims
Osteoarthritis is a condition that causes joints to become painful and stiff.
Research has demonstrated that individuals with knee osteoarthritis stand, walk and perform other activities with increased co-contraction (simultaneous activation) of the knee muscles: hamstrings and quadriceps. These muscle patterns will increase the stress on the knee joint and may speed up the progression of knee osteoarthritis. Importantly, despite the association between co-contraction and knee osteoarthritis, there are no physiotherapy approaches which aim to improve muscle coordination and reduce co-contraction in patients with this condition.
The aim of this study is to create a new biofeedback intervention using electromyography (EMG) technology. With EMG, small skin-mounted electrodes are used to measure electrical activity produced during muscle contraction. Although EMG technology has been used to develop biofeedback applications for conditions such as neck pain, a biofeedback application for knee osteoarthritis does not exist.
Following preliminary consultation with patients and physiotherapists, the researchers mapped out key components of a digital physiotherapy intervention for people with knee osteoarthritis. During this study, they aim to develop the different intervention components through an iterative approach, involving user consultation. The primary components of the intervention are:
1. Introductory video sequence – which explains key concepts and is watched before the first contact session
2. Physiotherapy assessment & patient report – used to map out and explain muscle tension patterns and abnormal muscle coordination
3. Tension release procedures – used to teach reorganisation of postural muscle activity in standing
4. Muscle coordination procedures – used to improve muscle coordination during functional tasks
5. Biofeedback software – used to assess muscle patterns and provide feedback to facilitate (3) and (4) above
By refining the intervention through continued consultation with people who have knee osteoarthritis, the aim is to develop a new intervention which can be delivered by physiotherapists. As part of this study, the researchers also plan to record reductions in pain so that they can develop an understanding of how effective the new treatment might be.

Who can participate?
Patients aged 40 - 80 years with knee osteoarthritis

What does the study involve?
All participants receive the intervention, typically attending for 6 face-to-face physiotherapy sessions with specific procedures to practice outside of contact sessions. After each session, participants are asked for their opinion of the treatment and for suggestions of how it could be improved.

What are the possible benefits and risks of participating?
The aim of the treatment is the reduce muscle tension and to improve knee pain. Participants may experience reductions in their knee pain after taking part. There should be no side effects from the treatment.

Where is the study run from?
The lead centre is the University of Salford, Manchester, UK. There will be four other local NHS trusts: Salford, Central Manchester, Stockport and Fairfield General Hospital Bury.

When is the study starting and how long is it expected to run for?
May 2018 to October 2020

Who is funding the study?
1. National Institute for Health Research (UK)
2. University of Salford (UK)

Who is the main contact?
Dr Stephen Preece

Trial website

Contact information



Primary contact

Dr Stephen Preece


Contact details

Health Sciences Research Centre
PO28 Blatchford Building
University of Salford
M6 6PU
United Kingdom
+44 (0)161 295 2273

Additional identifiers

EudraCT number

Nil known number

Nil known

Protocol/serial number

v3, HLRB25, CPMS 38156, IRAS 232749

Study information

Scientific title

The feasibility of using Biofeedback to rEduce Pain in people with Knee Osteoarthritis



Study hypothesis

There was no formal hypothesis as this study aimed to develop a new intervention through successive testing and iteration.

Ethics approval

Approved 18/05/2018, North West - Greater Manchester East Research Ethics Committee (3rd Floor, Barlow House, 4 Minshull Street, Manchester, M1 3DZ, UK; Tel: +44 (0)207 104 8009; Email:, REC ref: 18/NW/0282

Study design

Intervention development study

Primary study design


Secondary study design

Non randomised study

Trial setting


Trial type


Patient information sheet

See additional files


Knee osteoarthritis


The intervention development study will involve a physiotherapist (employed on the project) delivering successive iterations of the intervention to individual patients with KOA. One of the key principles of the intervention is that patients will only be able to reduce muscle activity in their knee muscles if they become aware of, and are able to change, more general patterns of muscle tension throughout their whole body. By employing an artist/animator on the project, the researchers propose to develop a range of instructional animations which will convey the idea of whole-body patterns of muscle tension. During the intervention testing session, the physiotherapist will work with the patient to explain (using the animations) their individual patterns of muscle tension. Then, using the biofeedback software, the therapist will then teach the patient to downregulate the activation of their hamstrings, quadriceps and gastrocnemius across different tasks. These tasks will gradually increase in difficulty until full walking is achieved. The researchers refer to these tasks as the incremental training activities (ITAs). Following each intervention session, patients will be asked to provide feedback on their perception of the three main components of the intervention: the biofeedback software, the incremental training activities and the instructional animations. They will also be asked for their opinion on how these supervised sessions could be continued at home (home practice component) and also on an introductory video which the researchers will develop to explain the key ideas of the intervention.

The researchers anticipate each session would last 1-2 hours and envisage delivering between 1-10 sessions depending on
the stage of the project. In addition to obtaining patient feedback after each individual session, they propose to carry out focus groups and individual interviews at three timepoints (Month 4, Month 11 and Month 16) to fully explore patient’s experiences and perceptions of the intervention. The data gathered from the focus groups/interviews, along with the individual feedback, will be used to improve the different components of the intervention. Specifically, the researchers will:
1. Improve the usability of the biofeedback software
2. Fully define an appropriate set of incremental training activities
3. Develop a library of easy-to-understand instructional animations which can be used with the different incremental training activities
4. Map out a home practice component
5. Develop an easy-to-understand introductory video which would be watched before the first intervention session

Through the procedures described above, the researchers will produce a fully defined intervention which will be formally evaluated in a follow-up study. Note that this project will not incorporate any formal evaluation of the intervention.

Intervention type



Drug names

Primary outcome measure

Pain measured using the knee injury and osteoarthritis outcome score (KOOS) at baseline and immediately after the end of the intervention (typically 6 sessions over 12 weeks)

Secondary outcome measures

There are no secondary outcome measures

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Knee OA participants will be included if they have a clinical diagnosis of knee OA, using the American College of Rheumatology (ACR) criteria. This is given as clinical presentation of pain in the knee and at least three of the following:
1. Age 40-80 years (note those under 50 must have a confirmed radiological diagnosis of knee OA)
2. Stiffness < 30 minutes per day
3. Crepitus
4. Bony tenderness
5. Bony enlargement
6. Palpable warmth

Full inclusion criteria are given below:
1. Age range of 18-80 (upper age limit to exclude people who may have limited mobility)
2. Ability to stand and walk independently
3. Speak and understand English to read the information sheet and sign consent form
4. Ability to walk without any assistive for at least 100 m (this is 100 m is not representative of the real demand of the testing, but we want to be sure participants will not get fatigued during the testing)
5. Clinical diagnosis of knee OA according to American College of Rheumatology (ACR) [37], see above, only for subjects with knee OA
6. Pain for at least 6 months' duration only for subjects with knee OA
7. Pain or difficulty in rising from sitting and/or climbing stairs, only for subjects with knee OA

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Complex pain conditions such as diabetic neuropathic pain, fibromyalgia
2. Dementia or other major cognitive impairment
3. Have had previous surgery to the lower limb
4. BMI >35 since it is not possible to obtain EMG muscle measurements on individuals with excess adipose tissue
5. Lower limb arthroplasty
6. Any systemic inflammatory disorders, such as rheumatoid arthritis
7. Any balance disorders which may increase the risk of a fall

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Salford Royal NHS Foundation Trust
Stott Lane Eccles
M6 8HD
United Kingdom

Trial participating centre

Fairfield General Hospital
Rochdale Old Rd, Bury
United Kingdom

Trial participating centre

Kingsgate House
First Floor Wellington Road North Stockport
United Kingdom

Trial participating centre

University of Salford
Frederick Road
M6 6PU
United Kingdom

Sponsor information


University of Salford

Sponsor details

Blatchford Building
M6 6PU
United Kingdom
+44 (0)161 295 5000

Sponsor type




Funder type


Funder name

National Institute for Health Research

Alternative name(s)


Funding Body Type

government organisation

Funding Body Subtype

National government


United Kingdom

Funder name

University of Salford Manchester

Alternative name(s)

University of Salford, University of Salford, Manchester, USM

Funding Body Type

private sector organisation

Funding Body Subtype

Universities (academic only)


United Kingdom

Results and Publications

Publication and dissemination plan

No additional documents will be made available as this is an intervention development study. The researchers aim to publish one intervention development paper in the journal BMC Musculoskeletal Disorders.

IPD sharing statement
The data sharing plans for the current study are unknown and will be made available at a later date.

Intention to publish date


Participant level data

To be made available at a later date

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

24/02/2020: The participant information sheet was uploaded as an additional file. 24/02/2020: The participant information sheet has been uploaded. 10/02/2020: Trial's existence confirmed by the NIHR.