Nonsurgical Versus Surgical Management of Femoroacetabular Impingement

What Does the Current Best Evidence Tell Us

Ian Gao, MD; Marc R. Safran, MD


J Am Acad Orthop Surg. 2021;29(10):e471-e478. 

In This Article

Abstract and Introduction


Controversy exists as to the management of femoroacetabular impingement (FAI). When nonsurgical management of symptomatic FAI fails, surgical management is generally indicated. However, many groups with a stake in patient care (particularly payors) have insisted on higher levels of evidence. Recently, there have been several Level I studies published, comparing physical therapy (PT) with hip arthroscopy in the management of symptomatic FAI. All of these studies have used outcomes tools developed and validated for patients with nonarthritic hip pain (the International Hip Outcome Tool). Most highest level evidence confirms that although patients with FAI do benefit from PT, patients who undergo surgical management for FAI with hip arthroscopy benefit more than those who undergo PT (mean difference in the International Hip Outcome Tool 6.8 [minimal clinically important difference 6.1], P = 0.0093). Future large prospective studies are needed to evaluate the effect on the outcomes when there is a delay in surgical management in symptomatic individuals, assess whether FAI surgery prevents or delays osteoarthritis, and determine the role of other advanced surgical techniques.


Symptomatic femoroacetabular impingement (FAI) is characterized as the abnormal contact between the proximal femur and acetabulum because of cam, pincer, or combined cam/pincer anatomic morphology. This pathologic repetitive contact with terminal ranges of hip motion can lead to labral tears, chondral damage, and subsequent osteoarthritis (OA).[1] FAI has become an increasingly recognized cause of hip/groin pain in young patients, and the prevalence of FAI morphology in the general cohort has been reported as 9% to 50%.[2–5] The prevalence of FAI morphology in the athletic cohort is even higher with reported rates of 95% in football,[6] 89% in basketball,[7] 50% to 72% in soccer,[8] and 85% in ice hockey.[9] However, many with FAI morphology do not develop symptoms.

Although it has been shown that cam FAI is associated with subsequent development of hip OA,[2,10,11] the relationship between pincer FAI and subsequent hip OA is unclear.[2,11,12] With cam FAI, for patients aged 45 to 65 years, when compared with patients with normal alpha angle (<55°), the odds ratio (OR) for end-stage hip OA at 5 years was shown to be 3.67 for alpha angle >60°, 9.66 for alpha angle >83°, and 25.21 for alpha angle >83°, and hip internal rotation <20°.[10] It has also been reported that the risk of subsequent OA increased by 5% (from baseline of 11%), and the risk of total hip arthroplasty (THA) increased by 4% (from baseline of 3%) for every increase in alpha angle degree >65°.[11] Although the odds ratio for OA with cam FAI morphology is markedly increased, the absolute risk remains low because only 11% of patients with alpha angle >60° and 25% of patients with alpha angle >83° went on to develop end-stage OA at 5 years.[10] Hartofilakidis et al[13] also showed that 82% of patients with asymptomatic FAI remained OA-free at 18 years follow-up. In addition, and most importantly, there currently is no evidence that the treatment of FAI prevents or delays future OA. Therefore, the goal for treatment of FAI in symptomatic individuals is to reduce symptoms and not to prevent OA.