Maybe these responses weren't intended to sound like they do, but I've got to say that OP hasn't asked if it was safe to crash, he hasn't indicated any fear of injury, and nothing that I saw implies that he isn't an experienced, skilled cyclist. He wanted to know if there is any risk assessment from bone density measurements, and complaining that the doctors aren't any help with that.

If there IS some heightened concern about crashing, that isn't the problem it appears to be made out to be here, and I respectfully suggest that those who haven't had to make that sort of risk assessment refrain from advising OP to take up a different sport. It's not helpful in my opinion. I've been there myself, and some of you probably figure me for half crazy because I biked when a crash would have likely been catastrophic. Wanting to know how to judge it, and being afraid or lacking in skills, are two different things. Use your judgement, decide how much risk you'll take. I think that's what OP is looking for.