7.01.109 Surgical Treatment of Femoroacetabular Impingement
Original MPC Approval: 08/12/2009
Last Review: 09/19/2011
Last Revision: 09/19/2011
Femoroacetabular impingement (FAI) is a structural abnormality in the hip joint that results in articulation abnormality of the femoral head and the acetabular rim. During flexion, altered mechanics result in compression of the labrum and / or articular cartilage in the acetabulum, with tearing and inflammation. Degenerative joint disease develops with inflammation, hip and groin pain, and decreased range of motion on flexion and internal rotation. Two different types of impingement, known as cam impingement, and pincer impingement, have been identified. In cam impingement, there is an asymmetric or nonspherical contour of the femoral head or neck that abuts against the acetabulum, resulting in cartilage damage and detachment from the subchondral bone. Pincer impingement is an overcoverage of the acetabulum that pinches and injures the labrum. The two types of impingement may occur singly or together. Impingement with damage to the labrum and / or acetabulum is felt to be a contributing factor to development of osteoarthritis of the hip, and that a significant percentage of patients with primary hip osteoarthritis may have been caused by FAI. The disease mainly appears to affect young to middle-aged adults, particularly those who engage in strenuous athletic activity.
Treatment of FAI is usually initiated with conservative therapies, including reduced activity and non-steroidal anti-inflammatory drugs. Physical therapy is usually not done because it aggravates the condition. Surgery is considered for patients that do not improve with conservative management.
The surgical technique for correcting the structural defects was first performed using an open technique that involved complete disarticulation of the hip joint. More recently, an arthroscopic technique is used wherein the femoral head is distracted from the joint to the point where the surgeon can inspect the articular surfaces thoroughly, and perform the necessary resection of overhanging acetabulum, trim torn labrum, and / or debride the cam area of the femoral head.
Open or arthroscopic surgery to treat femoroacetabular impingement is considered medically necessary. (See Provider Guidelines).
1. The technology must have final approval from the appropriate government regulatory bodies:
Osteoplasty and cartilage repairs of the hip joint are surgical procedures, and are therefore not subject to FDA regulation. The instruments used, e.g. arthroscopes, burrs, shavers etc,, as well as fasteners are subject to regulation by FDA, and a wide variety of surgical tools and hardware are available.
2. The scientific evidence must permit conclusions concerning the effect on health outcomes:
No randomized, controlled studies of FAI surgery have been found in a search of the peer-reviewed medical literature. There have been few prospective case series reported on outcomes using the open technique. Beck et al (2004) reported outcomes from 19 patients with confirmed clinical, radiographic, and MRI diagnosis of FAI after at least four years of follow-up post surgery. All had had labral damage, and 18/19 had acetabular damage. Five patients had undergone total hip arthroplasty (THA), and the remaining 13 were reported to have good to excellent outcomes. Peters et al (2006) reported outcomes of a prospective series of 30 hips (29 patients). 26 hips (25 patients) were diagnosed specifically with primary FAI. The 30 hips had either cam-type impingement (n=14) or mixed cam- and pincer-type impingement (n=15). 18 hips had severe cartilage damage not seen on MRI. At average 32 months follow-up, no progression to osteoarthritis (OA) was reported in 68% of the patients, but 4 (13%) subsequently developed OA. Five hips (17%) were expected to undergo THA. Two small retrospective studies (n=23 and 34, respectively) that included patients with severe cartilage damage reported that 50% to 70% of patients improved and 30% to 50% failed following open osteochondroplasty with dislocation. (Beaulé et al, 2007; Murphy et al, 2004).
The arthroscopic approach to FAI has only recently been developed. The literature search identified 4 prospective case series with at least 100 patients/hips, and one controlled cohort study. The largest prospective series was by Byrd and colleagues (2009) who reported on 200 patients/207 hips who had been treated arthroscopically for impingement from 2004-2007. Included were 163 hips with cam-type impingement, and 44 hips with combined cam- and pincer-type impingement. At 12 months, 100% were available for follow-up. At average 16 month follow-up, patients showed an average of 20 points improvement on the 91-point modified Harris Hip Score (MHHS). 83% of the group were considered improved. One patient underwent THA, and 3 required revision surgery. Philippon et al (2009) reported 2.3 year follow-up on 100 of 122 patients prospectively enrolled who underwent hip arthroscopy for FDI. 22 were lost to follow-up. Of the 100 remaining, 90 improved on the MHHS from average 58 to 84. 10 required THA. The authors noted that patients with a joint space of less than 2 mm were more likely to progress to the need for THA. Larson and Giveans (2008) reported outcomes of from 3 months to 3 years follow-up from a consecutive series of 96 patients/100 hips who presented with FAI between 2004 and 2007. Cam impingement was present in 17 hips, pincer impingement in 28, and mixed impingement in 55 hips. Following FAI surgery, impingement was reported to be improved in 86% of patients with 75% good-to-excellent. Three patients required THA. Pain improved significantly based on a visual analog scale. A small cohort study by Bardakos et al (2009) compared results from 24 patients treated for cam impingement with 47 patients with cam impingement, but underwent only repair of the labrum. There was a trend for improved MHHS outcomes in patients who were treated for cam impingement in addition to labrum repair. The results for 156 patients were reported by Sampson et al (2005), which was a preliminary study on the newly-developed technique. The authors state that for the majority of patients, pain relief was 50% after 6-12 weeks, 75% at 5 months, and 95% at one year.
The published evidence is limited, but permits some conclusions regarding health outcomes of patients with FAI. Surgical treatment is most effective in younger patients who are symptomatic, but without significant osteoarthritis or severe cartilage damage. There is a high probability that those with severe damage will not improve significantly following surgery, and may eventually require THA. The case series suggest that younger patients with moderate cartilage damage and without significant OA can attain improvement in the 75% to 85% range.
3. The technology must improve the net health outcome:
While the limited evidence in the literature permits some conclusions that patients with symptomatic FAI can benefit from surgery, there remain issues that may have an effect on net health outcomes. FAI has been recognized as a diagnostic entity only recently, and not a great deal is known about the natural course of the disease. While there appears to be an association with FAI and the development of OA, it is not known whether those with FAI morphology are more likely to have OA than those without, or which patients with FAI morphology are most likely to progress to OA. Those with cam-type impingement may follow a different time frame to further OA degeneration than pincer-type impingement. As there are limited outcomes data over short-to-intermediate terms, it is not fully known whether the treatment will reduce the occurrence of OA. Finally, it is not known whether the open or arthroscopic result in better outcomes and under what conditions. The open procedure is not without risks. In the series reported, the dislocation of the hip joint involves transection of the femoral neck, and nonunion was a complication reported in 27% of the patients studied (Peters et al, 2006).
4. The technology must be as effective as any established alternatives:
There are no surgical alternatives to either the open or arthroscopic osteochondroplasty. The only alternative is reduction of physical activity and use of non-steroidal anti-inflammatory drugs. Physical therapy is of no benefit, and is likely to aggravate the condition. Therefore one must consider that if the FAI pathology is not addressed surgically, there is the potential for worsening of the cartilage damage, to progression of osteoarthritis to a stage where a total hip resurfacing or total hip arthroplasty must be considered.
5. The improvement must be attainable outside the investigational settings:
At the present time surgery for FAI is still fairly new, and whether the open or arthroscopic technique is used, is a procedure that requires a high degree of technical skill. It is apparently not yet widely performed, and the number of surgeons trained in this technique is small. FAI has only recently been identified, so its prevalence in the population is still not well known. Therefore questions remain as to whether the degree of improvement reported in the case series can be expected outside of the investigational settings.
A search of the peer-reviewed literature was performed from June 2009 through June 2011. Findings in the recent literature support the medical necessity of surgical treatment of femoroacetabular impingement. Open or arthroscopic surgery remains medically necessary as outlined in the policy statement.
The following conditions are applicable to possible candidates for femoroacetabular impingement surgery:
The following were among the resources reviewed and considered in developing this policy. By reviewing and considering the resources, CareFirst does not in any way endorse the contents thereof nor assume any liability or responsibility in connection therewith. The opinions and conclusions of the authors of these resources are their own, and may or may not be in agreement with those of CareFirst.
Bardokos, N.V., Vasconcelos, J.C., Villar, R.N. (2008). Early outcome of hip arthroscopy for femoroacetabular impingement: the role of femoral osteoplasty in symptomatic improvement. Journal of Bone and Joint Surgery British90, 1570-5
Beaulé, P.E., LeDuff, M.J., Zaragoza, E. (2007). Quality of life following femoral head-neck osteochondroplasty for femoroacetabular impingement. Journal of Bone and Joint Surgery American89, 773-9.
Beck, M., Leunig, M., Parvizi, J. et al (2004). Anterior femoroacetabular impingement: part II. Midterm results of surgical treatment. Clinical Orthopaedics and Related Research 418, 67-73.
Blue Cross and Blue Shield Association (April, 2009; updated 2010, May). Surgical Treatment of Femoroacetabular Impingement (Medical Policy 7.01.118). Chicago, IL: Author.
Botser, I., Smith, T., Nasser, R., Domb, B. (2011, February). Open surgical dislocation versus arthroscopy for femoroacetabular impingement: a comparison of clinical outcomes. Arthroscopy. 27(2):270-8.
Byrd, J.W., Jones, K.S. (2009). Arthroscopic femoroplasty in the management of cam-type femoroacetabular impingement. Clinical Orthopaedics and Related Research467, 739-46.
Hayes Medical Technology Brief (2008; updated 2011, March). Arthroscopic Hip Surgery for Femoroacetabular Impingement (FAI). July 18, 2008. Lansdale, PA: Hayes, Inc.
Larson, C.M., Giveans, M.R. (2008). Arthroscopic management of femoroacetabular impingment: early outcomes measures. Arthroscopy 24, 540-6.
Matsuda, D., Carlisle, J., Arthurs, S., et al (2011, February). Comparative systematic review of the open dislocation, mini-open, and arthroscopic surgeries for femoroacetabular impingement. Arthroscopy. 27(2):252-69.
Murphy, S., Tannast, M., Kim, Y.J. et al (2004). Debridement of the adult hip for femoroacetabular impingement: indications and preliminary clinical results. Clinical Orthopaedics and Related Research 429. 178-81.
Peters, C.L., Erickson, J.A. (2006) Treatment of femoro-acetabular impingement with surgical dislocation and debridement in young adults. Journal of Bone and Joint Surgery American 88, 1735-41.
Philippon, M.J., Briggs, K.K., Yen, Y.M. et al (2009). OUtcomes following hip arthroscopy for femoroacetabular impingement with associated chondrolabral dysfunction: minimum two-year follow-up. Journal of Bone and Joint Surgery British 91, 16-23.
Sampson, T.G. (2005). Arthroscopic treatment of femoroacetabular impingement. Techniques in Orthopaedics 20, 56-62.
- Adolescent patients should be skeletally mature with closed growth plates. Adult patients should be too young to be considered an appropriate candidate for total hip arthroplasty.
- The patient is unresponsive to conservative therapy for at least three months.
- There is no evidence of advanced osteoarthritis, defined as Tonnis grade II or III, or joint space less than 2 mm.
- There is no evidence of severe chondral damage (Outerbridge grade IV)
This policy statement relates only to the services or supplies described herein. Coverage will vary from contract to contract and by line of business and should be verified before applying the terms of the policy.