Use and Effectiveness of Physical Therapy After Hip Arthroscopy for Femoroacetabular Impingement

Abstract

Background: Limited literature exists regarding how postoperative physical therapy (PT) may affect outcomes in patients with femoroacetabular impingement syndrome (FAIS) undergoing hip arthroscopy. Additionally, it is unknown how PT measures relate to traditional orthopaedic patient-reported outcomes (PROs). Purpose: To evaluate how the duration of PT may correlate with outcomes in patients with FAIS using both the Lower Extremity Functional Scale (LEFS) and standard orthopaedic PRO measures. Study Design: Cohort study; Level of evidence, 3. Methods: Patients from a single institution who underwent primary hip arthroscopy for FAIS between 2013 and 2016 were identified. Patients with a minimum 2-year follow-up and fully documented PT notes were included and stratified into 3 cohorts based on timing of PT discharge: 0 to 3 months, 3 to 6 months, and 6 to 12 months. Predictive regression models were developed to analyze the rate of improvement (ROI) in LEFS score as it relates to (1) postoperative day (POD) and (2) postoperative PT session number. Two-year PROs were collected, correlated with LEFS scores, and compared among cohorts. Results: A total of 95 patients were included (mean ± SD age, 34.6 ± 11.7 years; range, 14-55 years). Mean LEFS scores increased significantly from the initial score at 6 weeks, 3 months, and the time of PT discharge ( P < .01 for all). The predicted ROI in LEFS score was 3.39% per PT session for sessions 0 to 13, 1.43% for sessions 14 to 27, and 0.37% for sessions 28 to 40. Patients who underwent 3 to 6 months of PT had significantly better Hip Outcome Score (HOS) relative to the 0- to 3-month cohort and significantly better visual analog scale (VAS) scores for satisfaction relative to the 6- to 12-month cohort. The predicted ROI in LEFS score was 0.96% per day from POD 0 to 45, 0.22% from POD 46 to 139, and 0.03% after POD 139. Moderate correlations were seen between LEFS score at the time of discharge and all 2-year PROs as follows: HOS Activities of Daily Living subscale ( r = 0.488), HOS Sports-Specific subscale ( r = 0.500), modified Harris Hip Score ( r = 0.465), 12-item International Hip Outcome Tool ( r = 0.494), VAS pain score ( r = −0.346), and VAS satisfaction score ( r = 0.459). Conclusion: Patients undergoing hip arthroscopy for FAIS derived substantial benefit from each PT visit during their first 13 PT sessions and then a smaller, yet still meaningful benefit from sessions 13 through 27. After session 40, or approximately 4.5 to 5 months, patients no longer benefited from additional PT sessions. Based on PRO scores, patients discharged from PT between 3 and 6 months had the best 2-year outcomes. LEFS score had moderate correlation with orthopaedic PRO scores.