Association of Preoperative Walking Speed With 1-Year Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome.

Abstract

Background: Previous studies have identified demographic, radiographic, and intraoperative predictors of outcomes after hip arthroscopy for femoroacetabular impingement syndrome, yet few studies have identified whether preoperative gait metrics can predict outcomes.

Hypothesis: Increased preoperative step count, walking speed, step length, and gait symmetry will be associated with better outcomes after surgery.

Study design: Retrospective cohort study.

Level of evidence: Level 4.

Methods: Patients who underwent hip arthroscopy between 2019 and 2022 and downloaded the smartphone app rHip, allowing for retroactive access of gait metric data, were identified. Preoperative gait metrics, age, sex, body mass index (BMI), and exercise participation were analyzed via multivariate stepwise linear regression for a relationship with 1-year postoperative patient-reported outcomes (PROs), including Hip Outcome Scale-Activities of Daily Living (HOS-ADL); HOS-Sports Subscale (HOS-SS), and 12-item international Hip Outcome Tool (iHOT-12). Thresholds for preoperative gait metrics were analyzed via receiver operator characteristic curve. A subgroup analysis was performed to compare those who did and did not reach this threshold.

Results: A total of 43 patients (86% female; age, 33.1 ± 13.7 years; BMI, 23.9 ± 4.4 kg/m²) met inclusion criteria. Multivariate regression found that preoperative walking speed was significantly associated with postoperative HOS-ADL, HOS-SS, and iHOT-12 (P ≤ .01). A preoperative walking speed threshold of 1.065 m/s was predictive of outcome achievement. Those who failed to achieve this threshold were significantly older, of greater BMI, and less active (P ≤ .04). They also showed significantly worse 1-year postoperative scores (P ≤ .02) and lower PASS achievement for HOS-ADL, HOS-SS, and iHOT-12 (P ≤ .04).

Conclusion: Preoperative walking speed is significantly associated with 1-year outcomes after hip arthroscopy. Patients who averaged <1.065 m/s show significantly worse outcomes after surgery.

Clinical relevance: Assessment of preoperative walking speed may allow physicians to better counsel patients regarding expected outcomes after hip arthroscopy.