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right you are and you can have one without the other but I'm going by what KR said (I can only guess he was parroting what his spine specialist told him) and that was his spine (vertebra) had "cracked" (pars defect) and "slipped" (-listhesis). Lots of folks have one or both conditions and are symptom free but when you start...

In his pre-race interview with Georgia KR said that his injury wasn't new but it had recently "slipped and cracked" - that sounds like spondy (pars defect) to me. As long as it stays grade 1 or 2 and he can deal with the pain from time to time he'll be able to compete, but if it continues to progress...