Originally Posted by TrojanHorse

Thanks for your replies, and of course I agree with the general tenor about who's doing the work. I'm really at the "you'll need a knee when you're 60" stage, and I'm only 44. I can't run (at all!) and walking long distances is excruciating because I'm bone on bone and I have a pretty good case of osteoarthritis, but other than that my knee doesn't particularly limit my routine activities nor my ability to cycle (yet) so this is all very early for me.