Interventional procedure consultation document

Arthroscopic femoro-acetabular surgery for hip impingement syndrome

Treating hip impingement syndrome with arthroscopic femoro-acetabular surgery

Hip impingement syndrome is caused by unwanted contact between abnormally shaped parts of the head of the thigh bone and the hip socket. This results in limited hip movement and pain.

The aim of femoro-acetabular surgery is to improve range of movement and reduce pain. It is believed that it may also help prevent hip arthritis in later life. With the patient under general anaesthesia, a special camera (called an arthroscope) is inserted into the hip joint through a small incision. Using instruments inserted through one or two additional incisions, the surgeon removes some of the cartilage or bone, with the aim of reshaping the joint surface. Unlike open surgery, in arthroscopic surgery the hip joint does not need to be dislocated, and recovery is thought to be quicker.

The National Institute for Health and Clinical Excellence (NICE) is examining arthroscopic femoro-acetabular surgery for hip impingement syndrome and will publish guidance on its safety and efficacy to the NHS in England, Wales, Scotland and Northern Ireland. NICE’s Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisers, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about arthroscopic femoro-acetabular surgery for hip impingement syndrome.

This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:

• comments on the provisional recommendations
• the identification of factual inaccuracies
• additional relevant evidence, with bibliographic references where possible.

Note that this document is not NICE’s formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that NICE will follow after the consultation period ends is as follows.

• The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
• The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.

For further details, see the Interventional Procedures Programme manual, which is available from the NICE website (www.nice.org.uk/ipprogrammemanual).

Through its guidance NICE is committed to promoting race and disability equality, equality between men and women, and to eliminating all forms of discrimination. One of the ways we do this is by trying to involve as wide a range of people and interest groups as possible in the development of our interventional procedures guidance. In particular, we aim to encourage people and organisations from groups who might not normally comment on our guidance to do so.

In order to help us promote equality through our guidance, we should be grateful if you would consider the following question:

Are there any issues that require special attention in light of NICE’s duties to have due regard to the need to eliminate unlawful discrimination and promote equality and foster good relations between people with a characteristic protected by the equalities legislation and others?

Please note that NICE reserves the right to summarise and edit comments received during consultations or not to publish them at all where in the reasonable opinion of NICE, the comments are voluminous, publication would be unlawful or publication would otherwise be inappropriate.

Closing date for comments: 24 April 2011

Target date for publication of guidance: July 2011

1   Provisional recommendations

1.1  Current evidence on the efficacy of arthroscopic femoro-acetabular surgery for hip impingement syndrome is adequate for symptom relief in the short and medium-term, and there are no major safety concerns. Therefore this procedure may be used provided that normal arrangements are in place for clinical governance, consent and audit.

1.2  Arthroscopic femoro-acetabular surgery for hip impingement syndrome should only be carried out by surgeons with specialist expertise in arthroscopic hip surgery.

1.3  NICE encourages further research and data collection on arthroscopic femoro-acetabular surgery for hip impingement syndrome. Research studies should in particular address patient selection, and long-term outcomes (specifically relating to the development of osteoarthritis).

2   The procedure

2.1  Indications and current treatments

2.1.1  Hip or femoro–acetabular impingement results from abnormalities of the femoral head or the acetabulum. It can be caused by jamming of an abnormally shaped femoral head into the acetabulum (especially during flexion), or as a result of contact between the acetabular rim and the femoral head–neck junction. It is believed that it may lead to the development of osteoarthritis.

2.1.2  Symptoms may include restriction of hip-joint movement, pain and ‘clicking’ of the hip. Symptoms are typically exacerbated by hip flexion or prolonged sitting.

2.1.3  The management of hip impingement syndrome includes conservative measures, including modification of activity and non-steroidal anti-inflammatory medication. Patients with advanced osteoarthritic degeneration may require a total hip replacement.

2.2   Outline of the procedure

2.2.1  The aim of arthroscopic femoro–acetabular surgery for hip impingement syndrome is to reduce pain and improve the hip-joint range of movement.

2.2.2  The procedure is carried out with the patient under general anaesthesia. The hip is distracted using traction on the leg and an arthroscope and surgical instruments are inserted into the joint. Non-spherical sections of the femoral head, and prominent sections of the anterior femoral neck and acetabular rim are resected. Labral lesions are debrided using a shaver or radiothermal device, and the labrum may be repaired.

Sections 2.3 and 2.4 describe efficacy and safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the overview, available at www.nice.org.uk/guidance/IP/365/overview

2.3   Efficacy

2.3.1  In a non-randomised controlled study comparing arthroscopic femoro-acetabular impingement surgery with labral refixation (36 hips) versus arthroscopic femoro-acetabular impingement surgery with labral debridement (39 hips), mean Harris hip score (HHS) (on a scale from 0-100; higher scores better) was 94.3 points and 88.9 points respectively at 1-year follow-up (p = 0.029; both groups improved from baseline).

2.3.2  A case series of 200 patients (207 hips) reported that there was a mean improvement in HHS of 20 points (range −17 to 60 points) from baseline to a mean 16-month follow-up (significance not stated). In the same study, 1 out of 200 patients required total hip arthroplasty at 8-month follow-up due to persistent pain.

2.3.3  The case series of 112 patients reported an improvement in mean activities of daily living score (scoring system not described) from 70.0 points at baseline to 87.8 points at 2.3-year follow-up (p < 0.001). Similarly, mean sport activity score (scoring system not described) improved from 43.0 points at baseline to 69.0 points at 2.3-year follow-up (p < 0.001).

2.3.4  A case series of 96 patients (100 hips) reported that mean Short Form-12 quality of life score improved from 60.3 points at baseline to 81.4 points at 10-month follow-up after arthroscopic femoro-acetabular surgery (p < 0.01).

2.3.5  The case series of 96 patients reported that there was a significant improvement in femoral head-neck offset in 79 patients with cam type impingement lesions (p < 0.001) (absolute figures not stated).

2.3.6  The Specialist Advisers listed key efficacy outcomes as pain relief and delayed progression to osteoarthritis.

2.4   Safety

2.4.1  A case series of 183 patients (194 hips) reported pathological fracture (not otherwise described) in 1% (2/183) of patients. A case series of 97 patients (100 hips) reported femoral neck fracture (healed without surgery) in 1 patient.

2.4.2  The case series of 200 patients reported neurapraxia of the lateral femoral cutaneous nerve (resolved at 1-month follow-up) in 1 out of 207 hips. The case series of 96 patients reported 1 case of partial sciatic nerve neurapraxia for 24 hours.   

2.4.3  The non-randomised controlled study of 75 hips reported heterotopic ossification in 8% (3/36) of patients treated with labral debridement and in 0% (0/39) of patients undergoing labral refixation at a mean 19-month follow-up (significance not stated). Heterotopic ossification was reported in 1 out of 207 hips in the case series of 200 patients with a mean follow-up of 16 months. 

2.4.4  The Specialist Advisers listed adverse events seen or reported in the literature as genital trauma from traction post, neurological damage (sometimes related to traction), infection, postoperative hip dislocation, haemorrhage, pressure injuries to the perineum, and instrument breakage. They considered theoretical adverse events to include avascular necrosis and iatrogenic articular cartilage damage.

2.5   Other comments

2.5.1  The Committee noted that the available evidence was from observational studies.  While this was considered adequate for the present recommendation, further studies would be useful. The Committee recognised the difficulties of comparative research and acquisition of long-term data on this procedure.

3   Further information

3.1  This is a review of IPG 213 ‘Arthroscopic femoro-acetabular surgery for hip impingement syndrome’ published in 2007.

3.2  For related NICE guidance see www.nice.org.uk

Bruce Campbell

Chairman, Interventional Procedures Advisory Committee

March 2011

_{Personal data will not be posted on the NICE website. In accordance with the Data Protection Act names will be anonymised, other than in circumstances where explicit permission has been given.}

 _{It is the responsibility of consultees to accurately cite academic work in order that they can be validated.}