Pre-operative and Early Post Operative Oxford Scores as a Predictive Tool for Outcomes in Total Knee and Total Hip Arthroplasty

Background: The Oxford Hip and Knee Scores (OHS/OKS) are validated tools for measuring outcomes in joint arthroplasty. There is inconclusive evidence to support their use to predict clinical success. The aim of this study was to assess whether pre- and early post-operative scores are predictive of outcome at one year. Method: A retrospective cohort study collecting pre-operative, and four-week and one-year post-operative OKS/OHS. Linear regression analysis was used to establish the predictive capacity of these scores on outcomes at one year. Results: In both samples, the scores significantly increased over time ([Formula: see text] < 0.001). Lower pre-operative scores had a greater overall improvement ([Formula: see text] < 0.001) but achieved significantly lower scores at 1-year than those with higher pre-operative scores. Greater four-week OKS/OHS are predictive of higher scores, and change in scores, at one year. Older patients ([Formula: see text] = 0.018) with higher pre-operative scores ([Formula: see text] = 0.002) were more likely to have poor outcomes, with failure to meet the minimally important change (MIC) at four weeks 7x, and 8x more likely to do poorly at one year in the OKS and OHS samples, respectively. Conclusion: PROMs can be used as predictors of post-operative outcomes; however, further research is indicated in defining the thresholds for intervention success. Failing to meet the MIC in the early post-operative period results in significantly higher risk of poor outcomes at one year.