Smith SR, et al. - Using Markov modeling, experts assessed the cost-efficient of prolonged (35-day) and standard-duration (14-day) anticoagulation therapy after TKA. Aspirin led to the highest cumulative incidence of deep vein thrombosis [DVT] and pulmonary embolism, whereas prolonged fondaparinux resulted in the largest decrease in DVT incidence (15% decrease vs no prophylaxis). Irrespective of differential bleeding rates, all approaches had comparable incidence of prosthetic joint infection. The least costly strategy and the preferred regimen in the base case was prolonged rivaroxaban. In sensitivity analyses, prolonged rivaroxaban and warfarin had comparable possibilities of being cost-efficient. In conclusion, in comparison with standard 14-day prophylaxis, extending postoperative anticoagulation therapy to 35 days raises QALYs. Moreover, prolonged rivaroxaban and warfarin are most suitable to be cost-efficient after TKA and the costs of fondaparinux and low molecular weight heparin precluded their being chosen approaches.