Wound Complications Following Rivaroxaban Administration A Multicenter Comparison with Low-Molecular-Weight Heparins for Thromboprophylaxis in Lower Limb Arthroplasty

Background: The oral anticoagulant rivaroxaban is recommended for venous thromboembolic prophylaxis following lower limb arthroplasty. Concerns regarding high rates of wound complications following its use have prompted this multicenter comparison with low-molecular-weight heparins. Methods: English hospital trusts that replaced a low-molecular-weight heparin with rivaroxaban for thromboprophylaxis in lower limb arthroplasty during 2009 were identified. Prospectively collected national data for these units were analyzed to determine the thirty-day rates of wound complications and major bleeding (cerebrovascular event or gastrointestinal hemorrhage) and the ninety-day rates of symptomatic deep venous thrombosis (proximal or distal), symptomatic pulmonary embolism, and all-cause inpatient mortality before and after the change to rivaroxaban. A total of 2762 patients prescribed rivaroxaban following knee or hip arthroplasty were compared with 10,361 patients prescribed a low-molecular-weight heparin. Data were analyzed with use of odds ratios (ORs). Results: There were significantly fewer wound complications in the low-molecular-weight heparin group (2.81% compared with 3.85%; OR = 0.72, 95% confidence interval [CI] = 0.58 to 0.90; p = 0.005). There were no significant differences between the low-molecular-weight heparin and rivaroxaban groups in the rates of pulmonary embolism (0.55% compared with 0.36%; OR = 1.52, 95% CI = 0.78 to 2.98), major bleeding (OR = 0.73, 95% CI = 0.48 to 1.12), or all-cause mortality (OR = 0.93, 95% CI = 0.46 to 1.89). There were significantly more symptomatic deep venous thromboses in the low-molecular-weight heparin group (0.91% compared with 0.36%; OR = 2.51, 95% CI = 1.31 to 4.84; p = 0.004). Conclusions: The rivaroxaban group had a higher wound complication rate and a lower deep venous thrombosis rate; there were no differences in symptomatic pulmonary embolism or all-cause mortality. Longer follow-up is needed to assess any potential relationship between wound complications and joint stiffness, latent infection, and limb consequences of deep venous thrombosis.