Immobilization after trauma escalates risk of thrombosis. Our objective was to determine whether there is a difference in rates of deep vein thrombosis (DVT) after immobilization with plastic casts or routinely plaster of Paris in trauma patients. Despite both groups of patients do not show difference in blood coagulation tests (APTT, TT, PT, levels of fibrinogen and of D-dimer in plasma) during time of immobilization the evidence of DVT according to scintigraphy was lower in group of patients with plastic casts (3 per cent to 10 per cent).