Do We Need Chemoprophylaxis to Prevent Venous Thromboembolism following Medial Open-Wedge High Tibial Osteotomy?

The aim of this study was to investigate the overall incidence of venous thromboembolism (VTE) and to assess the efficacy of chemoprophylaxis to prevent VTE following medial open-wedge high tibial osteotomy (MOWHTO) in Asian patients. A total of 133 patients who consecutively underwent MOWHTO for the treatment of knee osteoarthritis with varus deformity were enrolled. All patients underwent preoperative ultrasonography and computed tomography venography on postoperative day 5 to detect deep vein thrombosis (DVT). Patients were divided into two groups: chemoprophylaxis group included patients ( n =66) who received 2.5mg fondaparinux for 5 days postoperatively, whereas control group comprised patients ( n =67) who received placebo (67 patients). We evaluated the efficacy and safety outcomes of the treatment. We also assessed the predisposing factors that may affect the occurrence of VTE. The incidence of overall DVT was 14.9% in the control group and 10.6% in the chemoprophylaxis group ( p >0.05). Proximal DVT occurred in one patient in the control group. There was no symptomatic DVT or pulmonary embolism in either group. The patients with DVT had significantly higher mean body mass index (BMI) than the patients without DVT. Multivariate logistic regression showed BMI>30kg/m (2) that was significantly correlated with the development of DVT (odds ratio=0.8; p =0.017). There were no cases of major bleeding; however, minor bleeding episodes occurred in four patients in the chemoprophylaxis group. The current study showed that the overall incidence of VTE following MOWHTO was low in Asian patients even without chemoprophylaxis. Therefore, routine chemoprophylaxis following MOWHTO seems to be not necessary in a population with low-VTE incidence. However, selective chemoprophylaxis should be considered in patients with BMI>30kg/m (2) .