Clinically significant outcome (CSO) thresholds are invaluable to the interpretation of patient-reported outcomes (PROs). The Patient-Reported Outcomes Measurement Information System (PROMIS) is gaining popularity among the orthopaedic community; however, CSO thresholds for PROMIS are yet to be defined for outcomes after gluteus medius and/or minimus (GM) repair. To (1) define CSO thresholds for PROMIS-Pain Interference (PROMIS-PI) and PROMIS-Physical Function (PROMIS-PF) after GM repair, (2) correlate these PROMIS scores with legacy hip-specific PROs, and (3) quantify their floor and ceiling effects. Case series; Level of evidence, 4. Consecutive patients who underwent primary GM repair between September 2017 and June 2021 with completed PROMIS at minimum 2-year follow-up were evaluated. The minimal clinically important difference, Patient Acceptable Symptom State, and substantial clinical benefit thresholds were defined for the PROMIS-PI and PROMIS-PF as well as for legacy PROs: Hip Outcome Score-Activities of Daily Living (HOS-ADL) and Hip Outcome Score-Sports Subscale (HOS-SS); modified Harris Hip Score (mHHS); 12-item International Hip Outcome Tool (iHOT-12); and the visual analog scale (VAS) for pain and satisfaction. Pearson correlations were performed between PROMIS scores and legacy PROs. Rates of floor and ceiling effects were quantified. Overall, 107 patients (81.7% follow-up compliance; mean age, 59.8 ± 8.8 years; 92.5% female; mean body mass index, 28.6 ± 6.3 kg/m2) were included in the analysis. GM tears were partial thickness in 56.1% of cases and treated endoscopically in 64.5% of cases. The minimal clinically important difference, Patient Acceptable Symptom State, and substantial clinical benefit thresholds, respectively, were as follows: PROMIS-PI (-4.6, 56.0, 52.6), PROMIS-PF (3.5, 42.7, 43.7), HOS-ADL (10.7, 68.2, 78.6), HOS-SS (16.5, 58.6, 60.6), mHHS (9.0, 64.3, 71.5), iHOT-12 (14.2, 63.6, 69.4), VAS pain (-16.1, 34.9, 28.1), and VAS satisfaction (not applicable, 70.9, 93.6). Moderate to strong correlations were observed between the PROMIS and legacy PROs. The PROMIS-PI showed a significant postoperative floor effect of 18.7%. Study findings indicated that the PROMIS is effective for use in GM repair patients, given the moderate-to-strong correlations between the PROMIS and legacy hip-specific PROs, the mostly limited floor and ceiling effects, and large effect sizes. Use of PROMIS instead of legacy PROs may aid in limiting survey burden.
Read full abstract