Body Mass Index, Sex, Tönnis and Outerbridge Grades, but Not Cam Lesion Location, Influence 10-Year Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome.

Abstract

Purpose: To investigate the 10-year outcomes of hip arthroscopy in femoroacetabular impingement syndrome (FAIS), comparing the impact of cam lesion location (superolateral, anterolateral, or anterior) on total hip arthroplasty (THA) conversion rates, revision rates, and patient-reported outcomes (PROs).

Methods: This retrospective cohort study evaluated patients who underwent primary hip arthroscopy for FAIS between 2010 and 2013. Included patients had preoperative radiographic evidence of cam lesions and a minimum of 10 years of follow-up data. Patients were categorized by cam lesion location: superolateral, anterolateral, or anterior. Outcomes included revision rates, conversion to THA, and PROs measured with the modified Harris Hip Score (mHHS) and Non-Arthritic Hip Score (NAHS) at 10 years. Statistical analyses were performed using independent t tests, analysis of variance, Fisher exact tests, and multivariable regression.

Results: A total of 157 patients were included, with a mean follow-up of 11.66 ± 1.08 years. The cohort included 93 patients with superolateral cam lesions, 38 with anterolateral lesions, and 26 with anterior lesions. Revision rates were 0% for anterior lesions, 7.89% for anterolateral lesions, and 4.3% for superolateral lesions (P = .3806). THA conversion rates were 7.69% (anterior), 2.63% (anterolateral), and 8.6% (superolateral) (P = .3558). 10-year mHHS (superolateral: 86.7 ± 18.85; anterolateral: 85.97 ± 18.76; anterior: 90.99 ± 11.61; P = .4932) and NAHS (superolateral: 83.92 ± 19.84; anterolateral: 84.73 ± 20.83; anterior: 89.62 ± 13.27; P = .4076) were comparable across groups. Achievement of the MCID was high across all groups, with 89.2% (140/157) of patients reaching the mHHS MCID and 91.1% (143/157) reaching the NAHS MCID with no significant differences by cam lesion location for either mHHS (P = .526) or NAHS (P = .999). Multiple linear regression analysis identified greater BMI (mHHS: P = .0005; NAHS: P < .0001) and female sex (mHHS: P = .0245; NAHS: P = .0115) as predictors of worse outcomes. Logistic regression analysis found that female sex (P = .0451), elevated Tönnis grade (P = .0015), and elevated Outerbridge grade (P = .0474) were associated with increased rates of THA conversion and revision.

Conclusions: Cam lesion location does not significantly affect revision rates, THA conversion, or long-term PROs. Factors such as BMI, sex, Outerbridge grade, and Tönnis grade are more influential on long-term outcomes.

Level of evidence: Level III, retrospective diagnostic comparative case series.