The D-KAF (Dalteparin in Knee-to-Ankle Fracture) Trial

It is known that patients who fracture their legs sometimes develop blood clots (known as deep vein thrombosis) in their legs. These clots may cause pain and swelling in the leg or they may detach and travel to the lungs producing shortness of breath, chest pain, and sometimes death. Unfortunately, it is not known how frequently these complications occur after leg fractures, or if the use of a blood thinner medication can effectively and safely prevent these clots. Doctors at hospitals across Canada are conducting a study in which patients who have surgery for leg fractures receive either a once-daily injection of a blood thinner, known as low molecular weight heparin, or a placebo injection for up to 14 days after their fractures. Neither the patients nor the doctors know which patient is on the medication and which patient is on placebo. All patients receive an ultrasound examination of their legs at 2 weeks after surgery to monitor for deep vein thrombosis. In addition, all patients are checked for symptoms of leg or lung clots and any side effects of the medication for 3 months. If the blood thinner is shown to be effective at reducing this complication and documented to be safe and cost-effective in this setting it will be recommended for use in such patients. If, on the other hand, the frequency of deep vein thrombosis is too low to justify the cost or inconvenience of taking this medication, this will also be an important finding.