The news on Damian Lillard’s persistent right calf injury was not good.

The veteran all-star Milwaukee Bucks guard was diagnosed with deep vein thrombosis (a blood clot in his lower right leg). He will be out of action for a significant period of time.

Here’s some additional information on deep vein thrombosis.

What is deep vein thrombosis (DVT)?

According to the Mayo Clinic, deep vein thrombosis is a blood clot that forms in one of the deep veins of the body, usually in the legs. It often causes pain, swelling or warmth in the leg. DVT can also occur without noticeable symptoms.

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Is deep vein thrombosis serious?

Yes, it can be very serious. If left untreated, clots can block blood flow to the heart if a pulmonary embolism develops (blood clot in the lungs).

What causes deep vein thrombosis?

Inflammation from an infection or injury are among the causes of DVT. Fractures and surgeries can also damage veins, which increase the risk of blood clots. Immobility for long periods of time is another common cause.

How is deep vein thrombosis treated?

According to the Mayo Clinic, treatments include anticoagulants (blood thinners), compression stockings and elevation.

What other NBA players have had DVT?

San Antonio Spurs star Victor Wembanyama is sitting out the remainder of the season due to DVT in his shoulder. Toronto Raptors forward Brandon Ingram, Pistons forward Ausar Thompson and former NBA star Chris Bosh are among other players that have suffered Lillard’s current injury. Tennis star Serena Williams has also suffered blood clots.

What’s the recovery time from a blood clot injury?

The timetable varies from several weeks to several months.