Objective To analyze the effect of arteriovenous impulse system (AVIS) combined with lowmolecular-weight heparins calcium (LMWHC) for prophylaxis of deep vein thrombosis (DVT) following total knee arthroplasty (TKA). Methods From March 2006 to March 2008, 76 cases of osteoarthritis patients (76 knees) accepted TKA, including 25 males and 51 females with an average age of 66.6 years (range, 58-79 years). The affected knees were left side in 41 cases and right side in 35 cases. They were randomly divided into experimental group and control group before surgery. Then LMWHC and rehabil itation training were routinely given in two groups before and after surgery. However, only experimental group was treated with AVIS continually during the first four days and then two times a day for 30 minutes one time during 5-7 days. At 7 daysd after operation, color Doppler ultrasound was used to detect the occurrence condition of DVT. Results Five cases (13.16%) had thrombosis of calf and recovered after treated with urokinase and salvia in the experimental group. Eleven cases had thrombosis of calf and 3 cases had thrombosis of whole low extremities (36.84%), and improved after treated with urokinase and salvia in the control group. There was significant difference in DVT incidencerate between two groups (P lt; 0.05). No pulmonary embol ism or death was found in both groups. Conclusion AVIScan effectively accelerate the venous blood return velocity, a combination of AVIS and LMWHC has a better effect in theprevention of DVT following TKA.