This parallel study is conducted in a single hospital. The participants are divided into two groups. One group is provided with Xarelto, and the other one group is provided without any prophylactic antithrombotic. To check the presence of a deep vein thrombosis of the lower limb, bilateral sonographic examinations are arranged for all participants preoperatively and at 3 and 14 days postoperatively. One radiologists who was blinded to the nature of the study interpreted the results of the sonographic examination. The present of pulmonary embolism, DVT-related symptoms, and complications are recorded during the 3-months follow-up in orthopedics outpatients. The symptom which associated with DVT is defined as the signs of leg such as unusual pain, edema, swelling, warm skin, and red or discolored skin. Complications related to Xarelto include major bleeding, infection, and non-healing wound. The expected number of participants in each group is 89, which is calculated by G * Power version 3.1. The intention to treat analysis is used in this study. The investigators compare the incidences of DVT, pulmonary embolism, and complications between the two groups.
Venous thromboembolism is a serious complication after total hip replacement (THR) and total knee replacement (TKR). Previous studies have reported the incidence of both asymptomatic and symptomatic deep vein thrombosis (DVT) after TKR were higher in Taiwan than other countries in Asia. Therefore, the usage of prophylactic antithrombotics should be considered. The efficacy and safety of Xarelto (Rivaroxaban) for preventing venous thromboembolism has been proved. However, there is a lack of study using prospective design to evaluate the efficacy and safety of Xarelto after THR and TKR for Taiwanese. In this study, the investigators use a randomized controlled trial design comparing the incidence of DVT, pulmonary embolism, and complications between intervention and control groups.