Minor Leg Injuries: A Common Cause of Blood Clots

Individuals suffering minor leg injuries are at increased risk for blood clots, a recent study shows. This risk applies primarily to deep venous thrombosis (DVT – a blood clot in the leg), and pulmonary embolisms (a clot that has traveled to the lungs) were studied as well.

Examples of minor leg injuries considered in the study are ruptures of the sural muscle (“tennis legs”), knee ligament ruptures, and knee and ankle sprains. The latter two were found to be associated with DVT to a lesser extent than tennis legs and knee ligament ruptures.

DVT is a condition that affects, on average, one to three people per 1,000, and is fatal to upwards of 5% of those with DVT, primarily due to pulmonary embolisms. With increasing world rates of obesity, strokes and other medical conditions, DVT is expected to be a persistent and increasing problem.

According to the study, which was conducted on 2,471 patients at Leiden University, Netherlands, 289 patients (11.7%), had suffered minor injuries within three months of venous thrombosis diagnosis, with the greatest connection being injuries within four weeks of diagnosis. 237 (82%) of these minor injuries occurred in the legs. Participants ranged from 18 to 70 years in age.

This is in comparison to only 154 (4.4%) of those 3,534 in the control group (subjects in the same study without DVT), which is just over one third of the percentage of patients in the experimental group (those being considered for minor leg injuries that did have DVT). In the control group, 78 (50.6%), of the 154 injuries occurred in the legs, again showing the connection between leg injuries and DVT in the experimental group.

Those with a genetic link to venous thrombosis (technically labeled as “factor V Leiden carriers”), were most likely to have blood clots develop following minor leg injuries. The study states that “A 50-fold increased risk was found in factor V Leiden carriers with a leg injury compared with non-carriers without injury.”

There are other factors that increase the risk of developing DVT, many due to poor blood circulation (such as stroke, surgery, obesity, advanced age, or excessive bed rest), and these groups too are more effected by minor leg injuries than those with good blood circulation.

The results of this study are potentially very helpful for doctors in recognizing the risk for DVT. If a doctor encounters a patient with a minor leg injury that has a family history of DVT, is obese, a stroke victim, or any other “high-risk” condition mentioned above, they will know there is a high risk in DVT resulting. Armed with this knowledge, preventative treatment for DVT can be administered early.

Source: Defeat Diabetes Foundation: van Stralen, Karlijn. Rosendaal, Frits. Doggen, Carine. Archives of Internal Medicine. “Minor Injuries as a Risk Factor for Venous Thrombosis.” January 2008.