Big Tea wrote: ↑
Wed Jun 10, 2020 6:40 pm
strad wrote: ↑
Wed Jun 10, 2020 6:30 pm
Thanks... One of the things I find interesting about DLC is the application to hip replacement parts since I have a few friends with hip replacements and they wear out....
As something so hard, slippery and 'thin' is available, would it not be a better method to just line the joint instead of hacking lumps out of people? Like, injecting a thin film between the moving surfaces, like a balljoint?
joints are relined with hemisphericalish titanium/PTFE liners eg in young dogs and young people eg Andy Murray
refacing the bone as necessary for installation - young bone will then regrow and bond to the back of the titanium
old people can't be refaced as their bone won't regrow suitably
they need a replacement joint that has integral pegs - to be glued into counterbores in the bones (my words)
the peg-and-counterbore works fine eg in a knee joint - because the loads are endwise
but not in a hip joint - because there's lateral load which tends to spread the counterbore and walk around (my words)
these days there's no wear problem with replacement joints
but there's a problem with replacement hip joint loosening and pain - this has no remedy (my words)
ie worldwide 95% of non-hip replacements are good over at least 25 years - but only 54% of hip replacements
on average hip joints are replaced at a patient age of 68
my doctors get paid £200 to defer indefinitely hip joint replacement in those whose clinical condition justifies replacement
good old NHS !