Periprosthetic Infection: Major Cause of Early Failure of Primary and Revision Total Knee Arthroplasty.

Revision total knee arthroplasty (RTKA) represents an effective treatment for failed TKA, but with less favorable outcomes. Considering the technical complexity and economic burden of RTKA procedures, it is mandatory to investigate current mechanisms and predictors for RTKA failure. The objective of this study is to evaluate the survivorship and determine the predominant causes of failure of RTKA. A total of 146 patients undergoing RTKA between 2003 and 2013 were identified from the institutional database. Revision was defined as surgery in which the whole prostheses (inlay and both femoral and tibial components) required exchange. Median follow-up was 6.3 ± 2.7 years (range: 2.2-10). Patient demographics, year of primary implantation, reasons for revision surgery, implant type, pain, knee mobility, systemic or local postoperative complications, and treatment of the complications were recorded and evaluated. Infection was a major cause of failure followed by aseptic loosening, instability, pain, malalignment, and inlay wear. Following RTKA, Knee Society Score (KSS) (knee score and functional score) demonstrated a significant improvement ( < 0.05). No significant difference in flexion, extension deficit, and KSS was detected between aseptic and septic primary TKAs preoperatively and following first RTKA. Reinfection rate of the septic primary TKAs was 5%. Infection was the major cause of a second revision, reaching as high as 50% in all cases. The results of this study support that septic failure of a primary TKA is likely to occur within the first 2 years following implantation. Septic failure of primary TKA does not influence survival of the revision prosthesis.