Mechanical measures in the prophylaxis of postoperative thromboembolism in total knee arthroplasty. Total knee arthroplasty patients are at high risk for deep venous thrombosis and pulmonary embolism. Prophylaxis against deep venous thrombosis and pulmonary embolism in these patients seems mandatory. Pharmacologic agents such as dextran 40, aspirin, and warfarin are effective but may be associated with significant complications such as drug reaction, bleeding, hematoma, and hemarthrosis. Heparin was not effective and was associated with significant bleeding complications. Mechanical methods such as continuous passive motion and sequential pneumatic compression stockings were without complications and seemed equal to or more effective than pharmacologic agents. Adding warfarin to mechanical methods did not seem to augment the antithromboembolic effect of the mechanical methods. 