Background: Revision TKA less consistently produces improvements in clinical function and quality of life when compared with primary TKA. The reasons for this difference are unclear.
Questions/purposes: We determined differences in patient-reported outcomes and rates of satisfaction between primary and revision TKAs, and determine whether the reason for revision influences patient-reported outcomes after revision TKA.
Methods: We retrospectively analyzed prospectively collected patient-reported outcome measures (PROMs) for 24,190 patients (23,393 TKAs; 797 aseptic revision TKAs). We compared patient-reported outcomes using the Oxford Knee Score (OKS), EuroQol (EQ-5D), and patient satisfaction between primary TKA and revision TKA, and for subsets of the revision TKA cohort. The followup data were collected between 6 and 12 months (7 months average) postoperatively.
Results: Improvements in the OKS (10) and EQ-5D (0.231) were smaller after revision when compared with primary TKA (OKS, 15; EQ-5D, 0.303). Patients who had revision TKA were less satisfied (66% versus 83%). Revisions for aseptic loosening or lysis were associated with the best patient outcomes (OKS improvement = 11; EQ-5D improvement = 0.232; satisfaction = 72%). Revisions for stiffness had the worst results (OKS improvement = 6; EQ-5D improvement = 0.176; satisfaction = 47%).
Conclusions: The early improvements in knee function and general health after revision TKA are only 69% to 76% of those observed for primary TKA. Levels of patient-reported knee function, general health, and satisfaction after revision are varied and related to the reason for revision. Even the best revision group does not approach the levels of function and satisfaction observed after primary TKA at a mean of 7 months postoperatively. Longer-term followup would be required to determine whether conclusions from these early data will need to be modified.
Level of evidence: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.