Background: Different causative factors for revision total knee arthroplasty (TKA) surgeries are elucidated in the arthroplasty registry data of different countries and the patient records at tertiary care centers. We aimed to determine the changes in the causes for revision TKAs before and after 2011 (The year that the Musculoskeletal Infection Society proposed a new definition for periprosthetic joint infection) and the changes in the demographics of patients who underwent revision TKAs during the same time intervals.
Methods: Patients who underwent revision TKAs between 2004 and 2017 were evaluated. A total of 291 patients operated before (period 1, n = 139) and after (period 2, n = 152) 2011 were included, while 53 patients with inconclusive diagnoses were excluded. The demographic data of patients and the causes for revision TKAs were collected and compared between the two periods.
Results: Infection was the most common cause of revision TKAs during periods 1 (58%) and 2 (48%). Aseptic loosening (46%) and infection (37%) were the 2 most common causes for late revisions during period 2. Aseptic loosening almost doubled during period 2 compared with that in period 1. Age, sex, and body mass index distribution in patients were similar across both the periods.
Conclusion: Although the incidence of aseptic loosening has significantly increased since 2011, infection is still the most common cause for revision knee arthroplasty surgery.
Keywords: Aseptic loosening; Periprosthetic joint infection; Revision knee arthroplasty.