Knee replacements.

[Boog]

Everyone's results may vary but my mother in law has had 3 knee replacements in her 93 years. The first one she had 30 or so years ago and that one only lasted a couple of years before the joint itself fell apart and had to be replaced. The other knee was replaced some years later. She is a bit heavy and mostly just sits around so she didn't wear them out.
But when your joints wear out there isn't much one can do but have them replaced I guess. Those shots don't usually last for long and you are limited as to how often you can have those.