Do wedgies happen that much outside of television shows anymore? I don't remember having it even mentioned in all of my years of school. I think they got thought up by writers trying to think of a good prank that teenagers could play. In my day, which was all of 2 years ago, unless college counts, in which case it's still my day, we enjoy the good old "circle game."
BTW, does that dictionary entry have an elaborated definition of the atomic wedgie?