[Epidemiology and etiopathogenesis of deep venous thrombosis of the lower limbs].

Deep venous thrombosis and pulmonary embolism are frequent complications of surgery. A careful evaluation of both the thromboembolic and the haemorrhagic risks depends on the type of intervention and associated individual risk factors. Such an evaluation should allow allocating the patient to an appropriate prevention which consists of mechanical and/or pharmacological means.