My friend Mary had a bad knee long ago, when we had young kids but at the time the doctor told her she could not have replacement surgery because it wouldn't last. Back then I'm sure things were way different. She did have the knee surgery a few years ago, not sure they tell you how long it's supposed to last now.'
I got this answer after I Googled "how long does knee replacement surgery last?"
Doctors first started replacing knees in the early 1970s. Back then, surgeons said the new knees would last about a decade or so. Today’s implants will last 20 years. By 2030, it’s estimated doctors will perform about 450,000 total knee replacement operations a year.