With two high-profile NBA stars suffering from blood clots recently, we asked doctors how they happen and if they are occurring more often.

It was a shock to the Milwaukee Bucks when Damian Lillard was given a diagnosis of Deep Vein Thrombosis. The blood clots have him ruled out indefintiely. If Lillard is forced to miss time into the playoffs, the Bucks will have a much harder time making a deep run in the playoffs. They are a much better team when they have Lillard out there.

Milwaukee Bucks star Damian Lillard was diagnosed with deep vein thrombosis in his right calf, the team announced Tuesday.The 34-year-old was placed on blood-thinning medication and will receive regular testing.