as i said, hip replacement normally works very well. my 80+ mother had two after two bad falls, both worked really well physically, but she went off the rails mentally after the second. apparently there is a theory (sorry, can't find link) that doing surgery like replacements releases a lot of fat into the bloodstream that can drive you nuts. that seems to be what happened to my mum.

i don't suggest anyone should not get a replacement based on my non-medic and probably wrong information.