Introduction

Prophylaxis against venous thromboembolism after joint replacement remains contentious.1 The incidence of deep vein thrombosis is between 45% and 75%.2 3 4 5 The rate of fatal pulmonary embolism is considered to be 1-3%,2 3 4 5 but this is a gross overestimate.1 Pharmacological techniques for preventing deep vein thrombosis (such as dextran 40, aspirin, warfarin, and heparins) are effective in reducing its incidence but are associated with important complications such as haemorrhage, wound haematoma, and haemarthrosis. 3 6 7 8

Mechanical methods such as intermittent pneumatic compression devices have been developed to avoid these problems. These provide similar prophylaxis against deep vein thrombosis 8 9 10 and are considered free of important complications.8 We report the occurrence of ulcers in patients using these devices according to approved guidelines.

Guidelines

Consideration of the evidence led the orthopaedic directorate of Glasgow Royal Infirmary and Stobhill NHS Trust to change its policy on prophylaxis against deep vein thrombosis at the end of 1995. Under the previous protocol heparin had been used in combination with graduated compression stockings. All patients having elective surgery who are at moderate or high risk of deep vein thrombosis now wear graduated compression stockings on both legs under pneumatic compression boots (AV Impulse System, Novamedix, Andover) (fig 1 …