Venous Thromboembolism Prophylaxis after Hip or Knee Arthroplasty

To the Editor: Anderson et al. (Feb. 22 issue)¹ found that extended prophylaxis with low-dose aspirin was not significantly different from rivaroxaban prophylaxis in preventing symptomatic venous thromboembolism after total hip or total knee arthroplasty. According to their exclusion criteria, patients who were receiving long-term anticoagulation were not included in the trial, and very few (2.4%) of all the patients who were enrolled had a history of venous thromboembolism.