Post-operative Oxford knee score can be used to indicate whether patient expectations have been achieved after primary total knee arthroplasty

Purpose: The aim of this study was to identify threshold values in the post-operative Oxford knee score (OKS) and change in the score for achievement of specific patient expectations and satisfaction, and whether failure to meet specific patient expectations influenced the rate of satisfaction after total knee arthroplasty (TKA). Methods: Prospectively complied data for 322 primary TKA were used. Patient demographics, and pre- and post-operative (1 year) OKS, and expectation fulfilment were collected. Patient satisfaction was also assessed 1 year post-operatively. Results: Patient pre-operative expectations varied in prevalence and differed according to gender, age, and severity of knee symptoms according the OKS. Fulfilment of patient expectations was variable and was dependent upon the specific expectation; the majority of patients achieved their expectation of pain relief and improved ability to walk (>70 %), however, few fulfilled their expectation to kneel or squat (<25 %). The threshold according to the post-operative OKS at which these expectations were achieved varied by more than ten points, ranging from ≥31 for pain relief to ≥42 for kneeling. Failure to fulfil patient expectations, for 15 of the 17 assessed, significantly increased the risk of dissatisfaction at 1 year (p < 0.05). Conclusion: The post-operative OKS can be used to predict the point at which the greatest proportion of patient expectations is achieved. Some expectations, however, are rarely fulfilled after a TKA and patients should be made aware of this pre-operatively which may improve their satisfaction post-operatively. Level of evidence: Retrospective comparative study, Level III.