Background and Aims Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit cycloxygenasa and it causes granulocytic function suppressio (1). These effects could be found in relation to the increased incidence of infections and higher risk of bleeding (2).

Aim of this study was a descriptive analysis of risk factors for total knee arthroplasty, in order to evaluate the relationship between NSAIDs and perioperative infection (4).

Methods A descriptive observational study in 25 patients medical records who were scheduled for total knee arthroplasty in University Hospital of Valladolid. The following variables were collected (table 1). The study was aprobed by Hospital Clínico Universitario de Valladolid with number (CEIm PI 19/1438). All patients signed the inform consent to enter the study.

Results Statistically significant differences were found in the rate of infection with respect to sex; being more frequent the infections in the feminine sex (p=0.042). Marginally significant differences were found between the taking of NSAIDs and infection of the prosthesis (p=0.1) although there was no statistical significance between the taking of NSAIDs and the analytical parameters of infection. This study demonstrates that periarticular infiltration does not increase the risk of infection (p <0.05)

Conclusions The use of NSAIDs has been associated with an immunosuppressive effect that leads to an increased risk of infection in total knee arthroplasty, so its use in the preoperative period should be limited. Female gender is other significative risk factor too. Our retrospective study has shown relationship between AINEs use and infection after knee arthroplasty.No increased risk of bleeding with AINEs in this sample.