How likely is it that i would get a waiver?

I kind of asked this question ealier, but i asked it wrong. I am going into 12 grade, but in 5th or 6th grade i dislocated 2 vertebre from a car wreck. I had to get adjustments and do traction for a few months, but i didnt need surgery or anything like that. Now my back is at 100% and doesnt bother me at all. I am planning on joining the marines, and i wanted to know how likely it was that they would give me a waiver or if i would even need one. I already told the recruiter about it, so i cant hide it from them.