Contemporary Revision Total Knee Arthroplasty in Patients Younger Than 50 Years: 1 in 3 Risk of Re-Revision by 10 Years

Background: There is a paucity of literature on contemporary aseptic revision total knee arthroplasty in patients ≤50 years. We sought to determine risk factors for failure in this population, with specific emphasis on survivorship free of (1) all-cause re-revision and (2) re-revision for instability. Methods: We retrospectively reviewed 135 nononcologic revision total knee arthroplasties (TKAs) performed from 2000 to 2012 in patients ≤50 years. Mean age was 43 years, and mean body mass index was 31 kg/m². Mean follow-up was 7 years. There were 99 (73%) first-time revisions, and 36 (27%) with prior revisions. Indications for revision included instability (47%), aseptic loosening (29%), and arthrofibrosis (9%). Multivariate Cox regression analysis was used to identify risk factors. Results: Survivorship free of all-cause re-revision was 66% at 10 years, with multiply revised TKAs (hazard ratio [HR] = 2.6, P = .008) having the poorest survivorship. Forty-three (32%) TKAs underwent re-revision including 10 (7%) for periprosthetic joint infection. Survivorship free of re-revision for instability was 88% at 10 years, with revision for instability (HR = 19, P = .03), male gender (HR = 3.0, P = .05), and multiply revised TKAs (HR = 3.5, P = .03) having poorer survival. Of the 64 TKAs revised for instability, 24 (38%) underwent re-revision, including 14 (22%) for recurrent instability. Conclusion: Patients ≤50 years undergoing contemporary aseptic revision TKA had a 1 in 3 risk of re-revision. Patients specifically revised for instability or had prior TKA revisions had the highest risk of re-revision at 10 years. Level of Evidence: IV.