Use and Effectiveness of Physical Therapy After Primary Gluteus Medius and/or Minimus Repair: A Duration- and Session-Sensitive Analysis

Background: Gluteus medius and/or minimus (GM) repair has been shown to provide improved patient-reported outcomes (PROs), yet few studies have established how postoperative physical therapy (PT) after GM repair affects patient recovery. Purpose: To (1) evaluate the trajectory of patient improvement after GM repair during PT and (2) identify how the duration of PT influences minimum 2-year PROs. Study Design: Case series; Level of evidence, 4. Methods: Patients who underwent primary GM repair between September 2012 and September 2021 were identified. The trajectory of their Lower Extremity Function Scale (LEFS) score improvement during PT was evaluated with regression modeling. The times of greatest change in LEFS improvement were identified, and the rate of improvement (ROI) per postoperative day and per PT session was recorded. Preoperative, 6-month, 1-year, and 2-year PROs were evaluated for the length of postoperative recovery. Patients were then stratified by their PT duration, and their preoperative characteristics and postoperative outcomes were compared. Correlations between LEFS scores at discharge and 2-year outcomes were evaluated. Results: In total, 69 patients were included with a mean age of 59.7 ± 9.2 years and a body mass index of 28.6 ± 6.1 kg/m 2 . The ROI was 1.89 LEFS points per session for sessions 0 to 21 and 0.04 LEFS/session after session 21. From postoperative day 0 to 81, the ROI was 0.56 LEFS/day, decreasing to 0.16 LEFS/day between days 81 and 134, and 0.03 LEFS/day after day 134. Nevertheless, significant postoperative improvements were observed until 1 year for all PROs ( P ≤ .023). Patients who completed between 3 and 6 months of PT showed superior 2-year Hip Outcome Score-Activities of Daily Living (HOS-ADL) and visual analog scale-pain (VAS-Pain) scores compared with patients who completed a shorter PT duration ( P ≤ .028). Conclusion: This study demonstrates that patients derived the greatest improvement during the first 21 PT sessions and 81 days after GM repair, with continued improvements after PT discharge up to 1 year. Patients who had <3 months of PT showed worse outcomes on LEFS scores at PT discharge and on 2-year HOS-ADL and VAS-Pain scores compared with patients who completed a longer PT duration. LEFS scores at discharge showed significant moderate and strong correlations with 2-year function and satisfaction scores.