The maximal gait speed is a simple and useful prognostic indicator for functional recovery after total hip arthroplasty

PURPOSE: The present study aimed to compare the capabilities of preoperative usual and maximal gait speeds in predicting functional recovery in patients who have undergone total hip arthroplasty (THA). METHODS: Primary and unilateral THAs were performed in 317 patients, and the proportion of patients who achieved unassisted walking (functional recovery) 5 days postoperatively was recorded as an outcome measure. Preoperative functional assessment included hip pain, leg muscle strength, range of motion (ROM), and gait speed evaluations. The capabilities of preoperative usual and maximal gait speeds in predicting functional recovery were compared based on the areas under the curves (AUCs) of receiver operating characteristic (ROC) curves. Further, ROC curves were constructed using two models: 1. a model of gait speed only and 2. a clinical model including age, sex, leg muscle strength, and ROM. RESULTS: On the AUCs for predictive ability of functional recovery, maximal gait speed was greater than usual gait speed (0.66 and 0.70, respectively). The AUC for maximal gait speed was as large as that of the clinical model (0.70 and 0.70, respectively). CONCLUSION: Our results suggest that maximal gait speed is a simple and useful prognostic indicator of functional recovery in patients who have undergone THA.