Does obesity affect outcomes in hip arthroscopy? A matched-pair controlled study with minimum 2-year follow-up

Background: Hip arthroscopy has gained popularity over the past decade, and its indications have broadened as newer techniques have been developed. However, there has been a paucity of literature evaluating the outcomes of hip arthroscopy in obese patients.

Purpose: To compare 2-year clinical outcomes of obese patients undergoing primary hip arthroscopy with matched nonobese controls.

Study design: Cohort study; Level of evidence, 3.

Methods: From February 2008 to February 2012, data were collected prospectively on all obese patients undergoing primary hip arthroscopy. A matched-pair nonobese control group was selected at a 1:2 ratio. All patients were assessed pre- and postoperatively with 4 patient-reported outcome (PRO) measures: the modified Harris Hip Score, Non-Arthritic Hip Score, Hip Outcome Score-Activities of Daily Living, and Hip Outcome Score-Sport Specific Subscale. Pain was estimated on the visual analog scale, and satisfaction was measured on a scale from 0 to 10.

Results: Sixty-two hips (62 patients) were included in the obese group and 124 hips (124 patients) in the control group. At preoperative baseline, the obese group had significantly lower PRO scores when compared with the control group. Both groups demonstrated statistically significant postoperative improvement in all scores (P < .05). Absolute scores were significantly lower in the obese group for all PRO measures, pre- and postoperatively. However, the improvement (delta) in PRO scores from pre- to postoperative time was not significantly different between groups. The rate of conversion to total hip arthroplasty, the rate of revision, and the complication rate were not significantly different between the 2 groups; however, rates of conversion to total hip arthroplasty and revision tended to be twice as high in the obese patients, but the study was not powered for these 2 outcomes.

Conclusion: Overall, obese patients had lower absolute PRO scores preoperatively and at 2-year follow-up. Both obese and nonobese patients demonstrated significant improvement in all PRO scores, and the change in scores were similar between groups. These results indicate that while obese patients may not have similar absolute scores after hip arthroscopy, they may show similar gains in improvement when compared with baseline. Hip arthroscopy appears to be a viable treatment option in the obese patient as long as expectations are adjusted accordingly.