Extended prophylaxis of venous thromboembolism in major orthopaedic surgery.

The risk of postoperative venous thromboembolism continues after discharge from the hospital. Studies in patients undergoing hip replacement or hip fracture surgery consistently found the rate of asymptomatic deep vein thrombosis to be substantially reduced by extended out-of-hospital prophylaxis and meta-analyses demonstrate symptomatic deep vein thrombosis to be reduced in parallel with asymptomatic. On the basis of these data, extended prophylaxis is recommended in hip replacement and hip fractures. The recommendation is particularly strong for patients with additional personal risk factors.