THURSDAY, Jan. 17 (HealthDay News) -- Minor leg injures -- including ankle sprains and muscle ruptures -- could raise the risk of blood clots in the legs or lungs, suggests a study by researchers in the Netherlands.

Previous research found that major injuries and related treatments such as surgery, a plaster cast, and extended bed rest increase the risk of venous thrombosis, which includes blood clots in the leg as well as more dangerous blood clots that have traveled to the lungs (pulmonary embolism). But the risk associated with minor leg injuries was unknown.

In this study, the researchers at Leiden University Medical Center studied almost 2,500 people who developed venous thrombosis between 1999 and 2004. They compared those patients with a control group of more than 3,500 people without venous thrombosis.

They found that 289 (11.7 percent) of the patients had sustained a minor injury in the three months prior to developing venous thrombosis, while just 154 (4.4 percent) of those in the control group had a minor injury in the three months before the study.

"Minor injuries that do not require surgery, a plaster cast or extended bed rest were associated with a threefold greater relative risk of venous thrombosis," the study authors wrote.

"The association appeared local, because injuries in the leg were associated strongly with thrombosis, while injuries in other locations were not associated with thrombosis. The association was strongest for injuries that occurred in the month before the venous thrombosis, suggesting a transient effect."

The researchers also found the association was stronger in people with genetic or other risk factors for blood clots.

The study was published in the Jan. 14 issue of the journal Archives of Internal Medicine.

More information

The Society of Interventional Radiology has more about deep vein thrombosis.