What is it?

A deep vein thrombosis (DVT) occurs when a blood clot forms in a vein, most commonly in the leg, and cuts off blood circulation. A pulmonary embolism (PE) is when a clot breaks off and travels from the bloodstream into the lung. According to the CDC, the rate of DVT and PE is 1-2 per 1,000 per year in the US. DVTs are not common in athletes, but various scenarios can cause them to form.

Symptoms/Risks

Travelling long distances to and from a competition, dehydration, trauma, immobilization, fractures, surgeries, smoking, obesity and birth control pills can put athletes at an increased risk of blood clots. Additionally, athletes may have a genetic clotting disorder which puts them at greater risk. Symptoms include swelling, cramping, warmth, skin discoloration or tenderness in an arm or leg.

Sports Medicine Evaluation and Treatment

If you have any symptoms of a blood clot, you should be evaluated by a sports medicine physician. These physicians will obtain a detailed history and physical exam while you are in the office. They will ask you about your family history and whether or not there is anyone in your family with a clotting disorder. They may order an ultrasound looking for clots in your veins or an MRI if the ultrasound is inconclusive. There is also a blood test that can be ordered, called a D-dimer, which will be elevated when blood clots are formed. Additionally, your physician may order lab tests to see if you have any conditions that causes you to clot easily. If a clot is found, you may be started on a blood thinner medication which will stabilize and help resolve your current clot and prevent your body from forming new clots.

Injury Prevention

In order to prevent blood clots, you should remember to remain hydrated and take breaks to stretch your legs when travelling long distances (roughly once an hour). If you have prolonged immobility in a cast, you may need prophylactic medication to prevent blood clots.

Depending on your discussion with your sports medicine physician and the likelihood of developing more clots, they may also recommend compression stockings or various other methods that can prevent other clots from forming.

Return to Play

After being diagnosed with a blood clot, you should refrain from activity for at least one month, which allows time for the clot to stabilize. This decreases the risk of the clot breaking off and traveling to the lungs. After a month of being on the medication, your doctor will guide you as to when to begin a return-to training program. This timing depends on a number of factors including your blood work, imaging findings, and sport.

Overall, you will start with a gradual increase in intensity while being monitored for signs of re-clotting. In general athletes that participate in sports with a high risk for bleeding-risk should not resume these activities until the full course of blood thinning medication is complete. Some of these sports include contact, impact and high-intensity sports such as cycling, boxing, rugby, football, baseball and soccer. You should speak with your physician to guide your individualized treatment and return to training. On average, in professional sports, athletes lose around six months of playing time.

AMSSM Member Authors
Jennifer Horawski MD, and Anthony Shadiack, DO

References
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