Which Total Knee Arthroplasty Revisions Do Not Improve Patient-Reported Outcomes?

Background: The literature comparing patient-reported outcomes of the same patient's primary and revision total knee arthroplasty (TKA) is nonexistent, and comparisons between revision and primary TKA are sparse. We aimed to fill this gap by comparing the Oxford Knee Score (OKS) and satisfaction for the same patient between their primary and revision TKA and assess these by different reasons for revision. Methods: We identified an 11,584-patient single-center TKA cohort of whom 382 patients went on to revision during 2005 to 2024. Patients answered OKS and satisfaction questionnaires as part of routine clinic visits, which we assessed preoperatively and postoperatively at years 1, 5, and 10 for both primary and revision TKA. We performed descriptive analyses and used logistic regression to estimate the association between patient characteristics and dichotomous outcomes. Results: Infection was the most common reason for first revision (N = 127) followed by instability, loosening, and stiffness. Patients revised for aseptic loosening/osteolysis reported the highest rates of satisfaction. OKS is lowest for patients revised for stiffness both before and after their revision (mean OKS 18.5 preop, 21.6 at 1 year). Furthermore, most of the patients who were not satisfied after their primary were not satisfied after their revision. Despite the low postrevision OKS, exactly half (50%) of patients revised for stiffness who were not satisfied after their primary TKA, reported being satisfied with their revision. Patients revised after 10 years were more likely to be satisfied a year after their revision than those revised in the first 2 years, odds ratio 9.7 (95% confidence interval 1.2-80.2). Conclusions: Patients who initially had good results and had a late failure of their primary TKA generally fared well after revision, especially when revised for mechanical issues such as aseptic loosening. Patients revised earlier, especially those with stiff knees or who had worse early satisfaction scores, were less likely to see benefits from revision. Level of Evidence: Level III retrospective cohort study. See Instructions for Authors for a complete description of levels of evidence.