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

Surgical Management: Hip Arthroscopy

Hip arthroscopy allows for a minimally invasive approach to treat FAI, and in recent years, the rate of hip arthroscopy has increased exponentially, with a 465% increase from 2005 to 2013.[21] Arthroscopic options include labral débridement or repair, femoral head/neck osteochondroplasty, acetabuloplasty, and chondral débridement or microfracture.

Hip arthroscopy has shown good clinical outcomes for the treatment of FAI with significant improvements in patient-reported outcomes and high rates of return to sport.[22] In a recent systematic review and meta-analysis, Minkara et al[22] reviewed 31 studies that evaluated the outcomes after arthroscopic management of FAI. With a total of 1981 hips (1,911 patients), with a mean age of 29.9 ± 1.9 years and a mean follow-up of 29.5 ± 14.0 months, they found that 87.7% of patients were able to return to sport after surgery, and mean patient-reported outcomes (including mHHS, Nonarthritic Hip Score NAHS, Hip Outcome Score Activity of Daily Living [HOS-ADL], Hip Outcome Score sports scale [HOS-SS], Visual Analog Scale, Short-Form Health Survey [SF-12], and iHOT) improved postoperatively (P < 0.05), with the highest increase observed in the HOS-SS (41.7 points, P < 0.001). The pooled risk of revision surgery (including revision hip arthroscopy or subsequent THA) was 5.5% (95% CI, 3.6% to 7.5%), and the risk of complications was 1.7% (95% CI, 0.9% to 2.5%) (most commonly heterotopic ossification, followed by transient neurapraxia).

Relatively new, evolving concepts of assessing outcomes after hip arthroscopy, such as minimal clinically important difference (MCID) and Patient Acceptable Symptomatic State, will continue to inform us of the best outcome tools in assessing patients after arthroscopic FAI surgery; however, validation of these tools are still needed in multiple populations before becoming the standard of outcomes reporting. In a case-control study, Nho et al[23] evaluated 935 patients (mean age 33.3 ± 12.3 years) after hip arthroscopy for FAI. At 2 years postoperative, 73% of patients achieved the MCID for HOS-ADL. Another case-control study by Cvetanovich et al[24] showed that of 386 patients at 2 years postoperative after arthroscopic FAI surgery, 79% of patients achieved the MCID for HOS-ADL and 63% of patients achieved the Patient Acceptable Symptomatic State for HOS-ADL, demonstrating that hip arthroscopy benefits most patients with symptomatic FAI but also highlighting the need to determine the factors that negatively affect the outcomes in certain patient populations.

Risk factors that have been shown to be associated with negative outcomes or failure of arthroscopic FAI treatment include greater age (58 vs 39 years, mean difference = 18, 95% CI 8 to 28, P = 0.001), female sex (OR, 13.3; 95% CI, 1.3 to 92.6), preoperative cartilage degeneration or OA (joint space < 2 mm) (OR, 14.6; 95% CI 5.1 to 41.8), worse mHHS preoperatively (OR, 3.2; 95% CI, 1.1 to 9.4), intraoperative labral débridement rather than repair (mHHS 84.9 for débridement vs 94.3 for repair, P = 0.001), and greater duration of symptoms (>1.5 years) before surgical intervention (Effect, 11.0; 95% CI 2.3 to 19.8).[22,25] Factors that have been shown to be associated with positive outcomes after arthroscopic FAI treatment include the type of athlete (professional, collegiate, and overhead athletes), the type of activity (hiking, jogging, biking, and aerobics), male sex, preserved joint space (>2 mm), and intraoperative labral repair (rather than débridement).[22]

The evidence on capsular closure during hip arthroscopy is evolving. A cohort study by Frank et al[26] compared clinical outcomes of patients undergoing hip arthroscopy for FAI (by a single surgeon) with complete capsular closure of T-capsulotomy versus partial closure of T-capsulotomy (closure of vertical incision, but open interportal incision). There were 32 patients in each group, and at an average follow-up of 29.9 ± 2.6 months, HOS-SS was markedly better and revision surgery rate was lower in the complete capsular closure group, but no difference in HOS-ADL and mHHS between groups was noted. A recent randomized controlled trial by Economopoulos et al[27] randomly assigned 150 patients undergoing arthroscopic FAI surgery (by a single surgeon) to three groups: T-capsulotomy without closure, interportal capsulotomy without closure, and interportal capsulotomy with closure. At 2 years follow-up, the capsular closure group had markedly higher mHHS and HOS-ADL compared with both groups without capsular closure. These studies suggest that the results of arthroscopic FAI surgery are better with capsular closure versus partial or no closure. Currently, a multicenter randomized controlled trial with 200 patients is being performed, comparing capsular closure versus noncapsular closure in arthroscopic FAI surgery,[28] which will further help determine the influence of capsular management on the outcomes after arthroscopic FAI surgery.

Hip Arthroscopy Versus Open Surgical Management

Recent systematic reviews have shown that hip arthroscopy provides equivalent or superior outcomes compared with open surgical hip dislocation for the management of FAI.[29–31] Nwachukwu et al[29] assessed 16 studies (nine open surgical hip dislocation studies and seven hip arthroscopy studies). The open studies included 600 hips with a mean follow-up of 57.6 months (4.8 years), and the arthroscopic studies included 1,484 hips with a mean follow-up of 50.8 months (4.2 years). With THA as an outcome end point, both hip arthroscopy and open surgical hip dislocation showed excellent and equivalent hip survival rates (93% for open and 90.5% for arthroscopic, P = 0.06), but hip arthroscopy was associated with a significantly higher average pooled score on the SF-12 compared with open treatment (58.4 for 560 arthroscopic hips vs 48.2 for 394 open hips, P < 0.001), indicating improved health-related quality of life benefits with hip arthroscopy. Zhang et al[30] assessed five studies that compared hip arthroscopy versus open surgical hip dislocation for FAI treatment and found that hip arthroscopy resulted in markedly higher NAHS at the 12-month follow-up, and markedly lower revision surgery rate, compared with open surgical hip dislocation. No difference in mHHS, HOS, or complication rate was noted at the 12-month follow-up.

Complications of Hip Arthroscopy

The complication rate and revision surgery rate for hip arthroscopy are relatively low. In a systematic review that included 92 studies and more than 6,000 patients who underwent hip arthroscopy, Harris et al[32] found that after hip arthroscopy, major complications (eg, deep infection, pulmonary embolism, osteonecrosis, femoral neck fracture, and dislocation) occurred at a rate of 0.58%, minor complications (eg, iatrogenic chondrolabral damage, temporary nerve palsy, superficial infection, deep vein thrombosis, and heterotopic ossification) occurred at a rate of 7.5%, and revision surgeries (eg, conversion to THA, periacetabular osteotomy, arthroscopic loose body removal, and arthroscopic lysis of adhesions) occurred at a rate of 6.3% at a mean of 16 months postoperative. THA was the most common revision surgery (rate of 2.9%). A separate PearlDiver database study by Truntzer et al[33] included over 2,500 patients who underwent hip arthroscopy, and they found that the major and minor complication rates within a 1-year postoperative period after hip arthroscopy were 1.74% and 4.22%, respectively. Major complications included deep infections, proximal femur fractures, osteonecrosis of the femoral head, hip dislocations, and pulmonary embolism. Minor complications included superficial wound complications, DVT, nerve injuries, bursitis, and heterotopic ossification. Conversion rate to THA within 1 year was 2.85%, and revision hip arthroscopy within 1 year was 6.87%. At 5 years postoperative, the conversion rate to THA was 4.74%, and the rate of revision hip arthroscopy was 8.92% (matched to laterality). This study also evaluated several major complications at 1 and 5 years postoperative and found a 0.89% and 1.08% rate of proximal femur fracture, and 0.58% and 0.77% rate of hip dislocation at 1 and 5 years postoperative, respectively (without matching for laterality) and 0.58% rate of osteonecrosis at 5 years (the one year rate was too small to report per Pearl Diver policy).

However, hip arthroscopy remains technically challenging, and it has been shown that revision surgery rate is directly related to surgeon experience. Mehta et al[34] showed that low volume hip arthroscopy surgeons (0 to 97 career cases) had 15.4% revision surgery rate, medium volume surgeons (98 to 388 cases) had 13.8% revision surgery rate, high volume surgeons (389 to 518 cases) had 10.1% revision surgery rate, and highest volume surgeons (≥519 cases) had only 2.6% revision surgery rate. Therefore, cases performed by surgeons with career volumes ≥519 cases had significantly lower risk of revision surgery (P < 0.0001) than those performed by lower volume surgeons, and cases performed by surgeons with lower career volumes had higher revision surgery rates than the overall revision surgery rates described previously by Harris et al[32] and Truntzer et al.[33]