Condition category
Musculoskeletal Diseases
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
The hip joint has two bones that fit together like a ball in a socket. In some people these bones press against each other and can cause pain. The medical term for this is femororacetabular impingement (FAI for short). Parts of the hip called the 'labrum' and 'cartilage' cushion the hip joint and allow the smooth friction-free movement. FAI can injure both the labrum and cartilage and also cause pain. There is now good evidence to suggest a link between FAI and the development of premature osteoarthritis (wear and tear) of the hip, but we do not know who best to treat FAI. There has been a rapid increase in the use of keyhole surgery to treat this condition. This operation is called 'hip arthroscopy'. During hip arthroscopy the patient is put to sleep and the surgeon passes a small telescope and tools into the hip joint through small cuts in the skin. The tools are used to reshape bone around the hip to prevent further impingement. Many patients have already undergone surgery and had improvements in pain and hip function in the short to medium term. However, this research was not compared to conventional care and it is possible that they may have similar levels of improvement without an operation. An alternative treatment option for patients is a course of best conventional care (a structured programme of exercise-based care supervised by a physiotherapist - this has been called personalised hip therapy) aimed at improving the muscle strength and control around the hip joint. There are fewer risks associated with this type of treatment and it is less expensive. We therefore propose a study to find out which of these two treatments is most effective for treating patients with FAI up to 12 months after treatment.

Who can participate?
The study aims to recruit 302 patients with hip pain, aged 16 and above.

What does the study involve?
Patients are randomly allocated to either undergo arthroscopic surgery or receive usual care. Participants will receive their allocated treatment and will then be required to complete some questionnaires at 6, 12, 24 and 36 months. At 12 months we will conduct our first analysis to measure the effectiveness of the two treatments.

What are the possible benefits and risks of participating?
There are no specific benefits to the participating patients, but future patients should benefit as the study will provide information on how best to treat this condition. The risks are small and include infection, bleeding, numbness, osteonecrosis (death of bone tissue) and neck fractures. For those patients allocated to usual care there is a small risk with pain medications and joint injections. However, the main risk is muscle soreness and temporary increases in pain from exercises.

Where is the study run from?
The study is run from 25 NHS Trusts throughout the UK.

When is the study starting and how long is it expected to run for?
It is expected that recruitment will start in July 2014 and participants will be enrolled onto the study over a 2-year period.

Who is funding the study?
National Institute for Health Research (NIHR) (UK)

Who is the main contact?
Prof. Damian Griffin

Trial website

Contact information



Primary contact

Prof Damian Griffin


Contact details

Warwick Clinical Trials Unit
Division of Health Sciences
Warwick Medical School
University of Warwick
Clinical Sciences Research Laboratories
Clifford Bridge Road
United Kingdom
+44 (0)24 7696 8618

Additional identifiers

EudraCT number number

Protocol/serial number

HTA 13/103/02

Study information

Scientific title

Full randomised controlled trial of Arthroscopic Surgery for Hip Impingement versus best CoNventional Care



Study hypothesis

What is the clinical and cost-effectiveness of hip arthroscopy for femororacetabular impingement (FAI) in comparison to best conventional care?

More details can be found at:
Protocol can be found at:

Ethics approval

NRES Committee West Midlands - Edgbaston, 01/05/2014, REC ref: 14/WM/0124

Study design

Multi-centre randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please contact Rachel Hobson ( to request patient information sheet.


Femoroacetabular impingement (FAI)


Participants will be recruited from 25 sites across the NHS in England, Scotland and Wales. Participation will be over a 3-year period. Participants will be allocated to either:
1. Hip Arthroscopic Surgery - performed by an experienced trained surgeon
2. Best Conservative Care - a package of physiotherapy-led therapy entitled 'Personalised Hip Therapy' given over a 12-week period with an option of two further booster sessions up to 6 months.

Intervention type



Drug names

Primary outcome measure

Clinical effectiveness of hip arthroscopy, assessed by patient-reported hip-specific quality of life after one year

Secondary outcome measures

1. General health status and health-related quality of life after 12 months
2. Pattern of clinical change over 12 months
3. Patient satisfaction with treatment and outcome after one year
4. Number and severity of adverse events after treatment
5. Need for further procedures up to three years
6. Cost-effectiveness within the trial and for a patient's lifetime
7. Develop and report processes to optimise recruitment in an RCT or surgery versus non-operative care
8. Fidelity of delivery of interventions

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Inclusion criteria as of 15/03/2016:
1. Age ≥16 (no upper age limit)
2. Symptoms of hip pain - patients may also have symptoms of clicking, catching or giving way
3. Radiographic evidence of pincer- and/or cam-type FAI morphology on plain radiographs and cross-sectional imaging, defined as:
3.1. Cam morphology - an alpha angle >55º;
3.2. Pincer morphology - a lateral centre edge angle of >40 degrees or a crossover sign on the anteroposterior radiograph of the pelvis
4. The treating surgeon believes the patient would benefit from arthroscopic FAI surgery
5. The patient is able to give written informed consent and to participate fully in the interventions and follow-up procedures

Original inclusion criteria:
1. Age ≥16 (no upper age limit)
2. Symptoms of hip pain - patients may also have symptoms of clicking, catching or giving way
3. Radiographic evidence of pincer- or cam-type FAI on plain radiographs confirmed with cross-sectional imaging, defined as alpha angle >55° or lateral centre edge angle >40°
4. The treating surgeon believes the patient would benefit from arthroscopic FAI surgery
5. The patient is able to give written informed consent and to participate fully in the interventions and follow-up procedures

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Evidence of pre-existing osteoarthritis, defined as Tonnis grade >1, or more than 2 mm loss of superior joint space width on AP pelvic radiograph
2. Previous significant hip pathology such as Perthes' disease, slipped upper femoral epiphysis, or avascular necrosis
3. Previous hip injury such as acetabular fracture, hip dislocation or femoral neck fracture
4. Previous shape changing surgery (open or arthroscopic) in the hip being considered for treatment

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Warwick Clinical Trials Unit, Division of Health Sciences
United Kingdom

Sponsor information


University Hospitals Coventry and Warwickshire (UK)

Sponsor details

c/o Mrs Ceri Jones (Research and Development Manager)
University Hospital
Clifford Bridge Road
United Kingdom
+44 (0)24 7696 5623

Sponsor type

Hospital/treatment centre



Funder type


Funder name

Health Technology Assessment Programme

Alternative name(s)

NIHR Health Technology Assessment Programme, HTA

Funding Body Type

government organisation

Funding Body Subtype

National government


United Kingdom

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date


Participant level data

To be made available at a later date

Basic results (scientific)

Publication list

2016 protocol in:
2018 results in:

Publication citations

Additional files

Editorial Notes

13/06/2018: Publication reference added. 02/09/2016: Publication reference added. 18/03/2016: Information regarding the availability of the participant level data has been added. 15/03/2016: The inclusion criteria have been updated and the target number of participants has been updated from 302 to 344.