Acceptance to medical school is contingent on getting an educational license from the college; part of the requirements for receiving the license is to include a criminal record check.
I am not exactly familiar with how a record would work but my understanding is that the juvenile record is not quite the same as the adult record. I obviously cannot comment on your own records or to what extent of severity they are, but I do know a few classmates who admit having a record for some minor misdemeanors and small infractions in their past. It seems like it might depend on severity of your charges.