Extended Venous Thromboembolism Prophylaxis Comparing Rivaroxaban to Aspirin Following Total Hip and Knee Arthroplasty (EPCAT II)

Blood clots in the legs and lungs are common complications following hip and knee replacement surgery. Guidelines state to give anticoagulants (blood thinners) for up to 14 days after knee replacement and 35 days after hip replacement. In this study we intend to prove whether aspirin works as well as blood thinners to prevent blood clots after hip and knee replacement surgery. Patients will be randomized (like a flip of a coin) to receive either aspirin or the blood thinner rivaroxaban after all patients receive a short course of anticoagulants following surgery. The rates of blood clot complications will then be compared in the two groups over a 90 day post-operative period. This study has the potential to show a cheap, safe medication is an effective alternative to anticoagulation therapy following THR or TKR which would result in considerable cost savings to the health care system.