Abstract
Purpose
The Oxford Knee Score (OKS) is a validated and widely used PROM that has been successfully used in assessing the outcome of knee arthroplasty (KA). It has been adopted as the nationally agreed outcome measure for this procedure and is now routinely collected. Increasingly, it is being used on an individual patient basis as a pre-operative measure of osteoarthritis and the need for joint replacement, despite not being validated for this use. The aim of this paper is to present evidence that challenges this new role for the OKS.
Method
We have analysed pre-operative and post-operative OKS data from 3 large cohorts all undergoing KA, totalling over 3000 patients. In addition we have correlated the OKS to patient satisfaction scores. We have validated our findings using data published from the UK NJR.
Results
Our data confirms of the effectiveness of the OKS in assessing the results of KA in populations of patients. Nearly all patients who undergo KA have an improvement in their OKS, regardless of the pre-operative score.
However, we have found that the pre-operative OKS cannot predict a poor outcome after KA and patients with the best pre-operative OKS have the best outcome as measured by patient satisfaction.
Conclusion
These data suggest that the OKS remains an excellent tool for assessing the outcome of knee arthroplasty in cohorts of patients, but further evidence is required of its validity for decisions regarding individual patients. Great care should be taken in using the pre-operative OKS to predict outcome after KA and its use in ranking patients need for surgery cannot be supported.
