Several reports have suggested that there is a strikingly low prevalence of deep vein thrombosis (DVT) and pulmonary embolism( PE) after total hip arthroplasty (THA) in Asian patients. We determined the prevalence of DVT and PE after the use of a mechanical compression device only without pharmacological thromboprophylaxis in 459 patients (516 hips). The overall prevalence of DVT was 4.8% (27 of 561 hips). Nine of 27 hips had proximal thrombi. Three patients (0.7%) had asymptomatic PE. In our patients, combinations of absent thrombophilic polymorphisms with low clinical prothrombotic risk factors led to a low prevalence of DVT and virtually no symptomatic PE. Therefore, mechanical compression device only suffices to prevent DVT and PE in Asian patients. (C) 2014 Elsevier Inc. All rights reserved.