Wu CT, et al. - Authors gauged the trend and the diagnostic effectiveness of D-dimer test on deep vein thrombosis (DVT) in patients with primary total knee arthroplasty (TKA) using rivaroxaban for thromboprophylaxis. Findings suggested the efficacy of rivaroxaban on reducing DVT in patients undergoing TKA. As all the DVTs occurred in the leg veins, poor accuracy of plasma D-dimer test in prediction or diagnosis of postoperative DVT could be resulted by decreased thrombus volume and size.