IS LESS REALLY MORE? Long-term outcomes of advanced arthroscopic techniques for patients with acetabular retroversion without anteverting periacetabular osteotomy

Objectives: Anterolateral acetabular over coverage, also known as acetabular retroversion, can cause femoroacetabular impingement syndrome (FAIS). Various surgical options have been suggested for treatment, ranging from anteverting periacetabular osteotomy to hip arthroscopy. The purposes of this study was (1) to report and analyze long-term patient-reported outcome scores (PROs) in patients with FAIS and labral tears in the setting of acetabular retroversion following hip arthroscopy and (2) compare these PROs with those of a propensity-matched benchmark control group without acetabular retroversion. Methods: Prospectively collected data were retrospectively reviewed for patients who underwent hip arthroscopy for FAIS and labral tear treatment between June 2008 and December 2013. On a well-positioned anteroposterior pelvic radiograph, retroversion was determined based on the presence of an ischial spine sign, >20% crossover sign, and presence of posterior wall sign. Inclusion criteria included acetabular retroversion. Outcomes measured included pre- and post-operative PROs for modified Harris Hip Score (mHHS), Non-arthritic Hip Score, Hip Outcome Score-Sports Specific Scale (HOS-SSS), International Hip outcome Tool (iHOT-12), Visual Analog Scale (VAS) for pain, patient satisfaction scores, rates of achieving the minimal clinically important difference (MCID), the patient acceptable symptomatic state (PASS),arthroplasty-free survivorship, and rate of revision hip arthroscopy. Propensity score matching was utilized to identify a control group without retroversion, defined by <20% crossover sign, and absence of ischial spine and posterior wall signs, and were matched 1:1 with similar age, sex, body mass index (BMI), acetabular and femoral head Outerbridge grade, preoperative lateral center-edge angle, and labral treatment. Results: A total of 106 hips with acetabular retroversion were matched to a control group. The groups showed no difference between demographic variables. The retroversion group was composed of 71 female and 35 male hips, with a mean SD age of 24.7 ± 7.9 years and follow-up time of 112.5 ± 29.9 months. Significant improvements were seen in all PROs collected in both groups, and the RA group showed significantly better iHOT-12, post operative VAS, and change in VAS compared to the control group ( P < 0.05). Intraoperative diagnostic data and procedures performed revealed a higher prevalence of cam and pincer morphology in the control group in addition to a higher incidence of femoroplasty while the RA group showed a higher rate of both acetabular chondroplasty and ACEA. Conclusions: Patients with acetabular retroversion who present with FAIS and labral tears can be safely treated using advanced hip arthroscopic techniques without reverse (anteverting) periacetabular osteotomy in a high-volume surgeon’s hands. Patients with acetabular retroversion demonstrated favorable PROs and low rate of revision arthroscopy and conversion to THA at long-term follow-up, which is consistent with a propensity-matched control group without acetabular retroversion.