Bones.

Organic_tube

The other day I was thinking about how bone transplants exist and so do grinders. So I was wondering why there only seems to be info online pertaining to this as a way of repairing something rather to get stronger, lighter, or better in some other way bones. Is this because of legal, financial, technical, or all of the above constraints?

Satur9

I suspect it's the low cost/benefit ratio, combined with the difficulty of finding someone qualified to do it and willing.