The crash is nasty. He doesn't get all the way around. NSFW obviously.

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SAN JOSE, Costa Rica (AP)—Jeremy Lusk, an American freestyle motocross racer, died of head injuries Tuesday after crashing while trying to land a backflip in competition. He was 24.

 

Jorge Ramirez, chief of the intensive care unit at Calderon Hospital where Lusk was taken, said the motocross racer suffered severe brain damage and a possible spinal cord injury.

 

Lusk won a gold medal at the 2008 X Games. He was injured Saturday night when he failed to complete a full rotation while attempting a Hart Attack backflip and slammed headfirst into the dirt. Lusk crashed in almost identical fashion in the freestyle semifinals at the 2007 X Games but was not hurt.

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 http://sports.yahoo.com/top/news?slug=ap-obit-lusk&prov=ap&type=lgns