Completely random question

I’ll post later about how awesome I’m doing (aside from my stomach getting mega-irritated thanks to my meds) and how active I’m going to be soon…ish, but first things first: Does anyone have any clue what they do with the bone flap and/or vertebrae removed during surgery? Do they throw it away? Because as gross as it is, I kind of want to see that. Well, if they cleaned if off first. I’m weird, I know, but I’m totally fascinated by every bit of anything medical, and I found one obscure site that said hospitals specially freeze the fragments for whatever reason. I’m just curious as to if that’s total poo or not lol