Defining the Minimal Clinically Important Difference and Patient Acceptable Symptom State After Endoscopic Gluteus Medius or Minimus Repair With or Without Labral Treatment and Routine Capsular Closure at Minimum 5-Year Follow-up

Abstract

Background: There is a paucity of information in the literature on midterm outcomes of endoscopic gluteus medius and/or minimus repair with concomitant labral treatment using only modern surgical techniques. Purpose: To define the minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) at a minimum of 5 years postoperatively for patients undergoing endoscopic hip abductor repair with routine capsular closure. Study Design: Case series; Level of evidence, 4. Methods: Consecutive patients who underwent primary endoscopic repair of gluteus medius and/or minimus tears between January 2012 and December 2015 by the senior author were eligible for inclusion. Patient-reported outcome scores were assessed preoperatively and at 5 years postoperatively: Hip Outcome Score–Activities of Daily Living (HOS-ADL), HOS–Sport Specific (HOS-SS), modified Harris Hip Score (mHHS), 12-item International Hip Outcome Tool (iHOT-12), and visual analog scale (VAS) for pain. The MCID was uniquely calculated using the distribution method, and the PASS was determined via the anchor-based method utilizing receiver operating characteristic curves and Youden index. Results: A total of 46 patients were included in the study. The majority were female (87.0%), with a mean ± standard deviation age of 59.1 ± 8.9 years and body mass index of 27.3 ± 6.9. Significant postoperative improvements (P < .001) in each of the 5 patient-reported outcomes were observed at 5 years postoperatively. The MCID threshold values were calculated as follows: HOS-ADL, 11.5; HOS-SS, 15.1; mHHS, 13.3; iHOT-12, 11.8; and VAS, 15.8. The PASS thresholds were calculated as follows: HOS-ADL, 75.7; HOS-SS, 79.7; mHHS, 81.2; and iHOT-12, 60.8. A majority of patients achieved a clinically significant outcome, with 96.2% of patients reaching a threshold score for the MCID or PASS for at least 1 patient-reported outcome. Conclusion: Endoscopic hip abductor repair with concomitant arthroscopic labral treatment has a high rate of achievement of clinically significant outcomes and survivorship at a minimum 5-year follow-up. We defined the MCID for the HOS-ADL, HOS-SS, mHHS, iHOT-12, and VAS outcome scores to be 11.5, 15.1, 13.3, 11.8, and 15.8, respectively. The PASS threshold scores for the HOS-ADL, HOS-SS, mHHS and iHOT-12 scores of 75.7, 79.7, 81.2, and 60.8, respectively. Future researchers and clinicians can use the MCID and PASS values established in this study to better evaluate mid-term outcomes of patients undergoing hip abductor repair.