Trends and Epidemiology in Revision Total Knee Arthroplasty: A Large Database Study.

Background: As the volume of primary total knee arthroplasty (TKA) continues to grow, the clinical and financial burden of revision total knee arthroplasty (rTKA) is expected to increase. The purpose of this investigation was to characterize contemporary indications and complications for rTKA.

Methods: Patients undergoing rTKA between 2010 and 2021 were identified within an administrative claims database. Adjusted rTKA incidence was calculated by dividing the annual rTKA volume by the annual primary TKA and multiplying by 100,000. Mann-Kendall trend tests were utilized to trend revision volume, etiology, 90-day postoperative complications, and patient demographics.

Results: A total of 397,367 rTKA were identified over our study period, of which 287,492 (72.4%) had coding regarding revision etiology. The volume of annual rTKA (31,091 to 33,850; P = 0.451) did not change over the study period. The adjusted incidence of rTKA decreased (25,568.3 to 19,272.2 per 100,000 annual TKA; P = 0.011). The leading causes of revision TKA were infection (21.2%), aseptic implant loosening (19.3%), and instability (9.8%). The rate of septic revision (4,710.5 to 4,426.1 per 100,000 annual TKAs) and aseptic implant loosening (4,502.5 to 3,636.4 per 100,000 annual TKAs) did not change (both P values > 0.05). The rates of instability increased (1,369.2 to 2,609.85 per 100,000 annual TKAs; P = 0.007). The rates of postrevision surgical site infection, periprosthetic joint infection, deep vein thrombosis, and transfusion decreased over the study period, while rates of emergency department visits and readmission increased (all P values <0.05).

Conclusions: The incidence of revision TKA may be slowing. While the risk of revision for infection and aseptic loosening remains unchanged, revision for instability has increased. The rates of postoperative complications appear to have decreased. Improved surgical technique, implant design, and perioperative protocols may have contributed to these findings. Continued work is necessary to reduce the risk of failure and postoperative complications.