The purpose of this study was to investigate the effectiveness of intermittent pneumatic compression of the plantar venous plexus with the newly developed arteriovenous impulse system. Seventy-four patients about to undergo primary unilateral total hip arthroplasty for osteoarthrosis, all receiving a standard thrombosis prophylaxis regime of thigh-length anti-embolic stockings, 5,000 IU heparin delivered subcutaneously twice daily, and 400 mg hydroxychloroquine sulfate delivered twice daily, were entered in a prospective trial. The patients were allocated at random to also receive the arteriovenous impulse system on the foot of the operated side. On approximately postoperative day 12 bilateral ascending venography was performed. There were 44 patients in the nonpumped group and 30 patients in the pumped group. The incidence of deep venous thrombosis was 6.6% in the pumped group and 27.27% in the nonpumped group. The incidence of thrombosis was significantly lower in the pumped group (P < .025). The authors conclude that chemical prophylaxis plus the use of the mechanical, pneumatic, and arteriovenous impulse system reduces the incidence of thromboembolic complications further than chemical prophylaxis alone.