Letter to the Editor on “Rivaroxaban Use for Thrombosis Prophylaxis is Associated With Early Periprosthetic Joint Infection”

To the Editor:
The concern expressed by Brimmo et al [1] regarding the increasing incidence of surgical site infection, as greater efficacy is achieved with deep vein thrombosis prophylaxis, is shared by all experts in the field.

Measures of association in a retrospective cohort, as used in their study, would be useful in the absence of data obtained with more robust experimental designs. Albeit with a different definition of infection than that used by the authors, the incidence of infection with rivaroxaban was studied extensively in the Regulation of Coagulation in Orthopedic surgery to prevent Deep vein thrombosis and pulmonary embolism (RECORD) randomized controlled trials 2, 3, 4, 5. No statistical differences in safety were found when comparing rivaroxaban to enoxaparin in 2509 patients undergoing hip arthroplasty [3] and 3148 patients undergoing knee arthroplasty [5]. To test for external validity, the Xarelto (R) in the prophylaxis of post-surgical venous thromboembolism after elective major orthopedic surgery of the hip or knee (XAMOS) trial was designed as a prospective cohort study [6] comparing rivaroxaban to various pharmacological agents in 15,000 patients, where no statistical differences with regard to infection were found.