mechanical versus drug prevention of thrombosis after total hip endoprosthesis implantation a randomized controlled clinical study pharmacological prophylaxis is routinely applied after total hip replacement although it effectively reduces deepvein thrombosis side effects bleeding haematoma swelling thrombocytopenia are not infrequent since in germany use of foot pumps as only means of prophylaxis is unpopular we investigated their efficacy and safety in a randomized study 106 patients used either low molecular weight heparin fraxiparin sanofisynthelabo germany or the footpump av impulse system orthofix mhltal germany and were monitored for deepvein thrombosis using serial duplex sonography on postoperative days 4 12 and 45 clinical observations included daily measurements of thigh circumference recording of postoperative drainage amounts and monitoring of wound healing none of the 50 patients treated with the footpump developed deepvein thrombosis while 4 of the 50 patients 8 per cent on pharmacological prophylaxis did so six patients stopped using the footpump during the study one patient developed heparininduced thrombocytopenia patients on mechanical prophylaxis had smaller amounts of drainage mean 247 ml vs 272 ml p 0485 and significantly less swelling of the thigh 10 mm compared with 15 mm p or 0001 the good results in terms of prevention of thromboembolic complications and soft tissue swelling favour the general use of foot pumps as mechanical prophylaxis