The study by Nakao et al. investigated the validity of utilizing gait speed as a preoperative metric for predicting outcomes after total hip arthroplasty (THA). The study included 274 patients who underwent THA for osteoarthritis and focused on whether their preoperative gait speed correlated with their midterm outcomes, which were measured with use of the Forgotten Joint Score-12 (FJS-12) and the Oxford Hip Score (OHS) at a mean of 6.7 years postoperatively. Patient Acceptable Symptom State (PASS) thresholds and a K-means clustering approach were utilized to identify specific gait speed cutoffs associated with improved patient-reported outcomes. The authors found that preoperative gait speed predicted OHS and FJS-12 values, that hip flexion range of motion and hip flexion strength were associated with preoperative gait speed, and that preoperative gait speed values above 0.7 m/s and 1.0 m/s were associated with achieving the PASS for the OHS and FJS-12, respectively. Additionally, on K-means clustering analysis, they identified a preoperative gait speed of 1.0 m/s as the sole contributor to classification into the excellent outcome group. This study is unique in that it evaluated preoperative gait speed as a clinical metric in the context of patient-reported outcomes after THA. The 10-Meter Walk Test has been validated as a reliable gauge of functional health1. Research has shown that slower walking speeds are predictive of frailty, hospitalization, falls, and mortality2. Gait speed has been correlated with functional independence, mobility, and recovery following joint replacement3. The results suggest that gait speed may provide additional information beyond traditional demographic variables such as age. Clinically, providers may choose to evaluate gait speed during preoperative assessments in order to counsel patients about their likely outcomes. A patient with a slower preoperative gait speed may be advised of a higher risk of persistent symptoms, whereas a patient with a speed of >1.0 m/s may be counseled regarding improved expected outcomes. However, the data cannot confirm whether gait speed is a modifiable factor or just a predictor of outcomes. Prehabilitation could be considered to improve gait speed, but the current evidence regarding its utility is limited. This study has several strengths. The study population had a relatively long mean follow-up of nearly 7 years, and both a clustering analysis and PASS thresholds were utilized to define the outcome categories. The use of 2 methods to establish metrics for evaluating good outcomes strengthens the finding that gait speed is predictive of improved outcomes. The patients’ gait speeds were also measured routinely the day before surgery, as a part of standard clinical care. This demonstrates that gait speed could be incorporated into routine practice with little additional burden. However, this study has a few limitations, which should be investigated further. Factors such as bilateral limb disease, spinal pathology, or other comorbidities could have influenced both gait speed and outcomes. The study population may only reflect the local epidemiology, and further studies should evaluate these findings for generalizability. Multicenter studies with larger populations could confirm whether the 1.0 m/s threshold is consistent across populations. Interventional studies could also evaluate whether improving gait speed through prehabilitation improves postoperative outcomes or whether gait speed is a non-modifiable predictor. In summary, the study by Nakao et al. adds to the body of literature supporting gait speed as a valuable metric of functional health and outcomes after THA. Clinically, gait speed can be considered a useful preoperative health assessment metric that could be used to guide patient counseling.
Tang et al. (Wed,) studied this question.