Cost-effectiveness analysis of pharmacologic DVT prophylaxis following select foot and ankle surgeries

Venous thromboembolism disease (VTED) affects 300,000 to 600,000 people and is the proximate cause of more than 60,000 deaths each year in the United States. While low molecular weight heparin (LMWH) is routinely prescribed following many high-risk orthopedic surgeries to prevent VTED, it is infrequently used following foot/ankle surgery (1). A recent clinical consensus statement published by American College of Foot and Ankle Surgeons concludes that routine chemical prophylaxis is not warranted when caring for foot/ankle disorders; rather, the authors recommend that patients should be risk stratified by their provider and have a VTED prevention plan (which may or may not include use of LMWH) tailored to their individual risk level (2). Because the rate of VTED development varies greatly after foot/ankle surgery (anywhere from 4% with hallux valgus surgery [3] to as much as 36% in Achilles tendon surgery [4]), it is possible that the decision to provide pharmacologic prophylaxis from a cost analysis perspective may be entirely explained—in some instances—by the type of surgery alone. In this work, using a formal cost-effectiveness analytic approach, we explored whether certain types of foot/ankle surgeries or postoperative conditions might warrant the use of routine prophylaxis with LMWH regardless of patient factors. In this presentation, we describe our findings regarding the cost-effectiveness of using LMWH to prevent VTED during the postoperative period for five commonly encountered clinical scenarios: 1) Achilles tendon repair, 2) total ankle replacement (TAR) surgery, 3) hallux valgus surgery, 4) midfoot/rearfoot arthrodesis surgery, and 5) cast immobilization and nonweight-bearing.