Theoretical question about bone replacement

[MrWithay]

I hope this topic has found roots in the correct forum, if not - I apologise.

I'm here after my research has hit somewhat of a dead end.
In short, I am working on a fantasy novel which involves a character than can transform bone into glass.
The blood vessels, connecting tissue and surrounding flesh would be unchanged, just the bone cells and marrow.

My questions are:

1- What would the immediate side effects be to the victim if the glass was strong enough to support their weight?

2- How long could a person survive with a completely artificial skeleton?

3- What side effects would occur with having a partially artificial skeleton?
For this last question my research has led me to gangrene, but I'm wondering if there's other symptoms I may have overlooked.


Thank you in advance for your time and I look forward to hearing from folk much smarter than myself.