I have a slightly torn meniscus and at the time surgery wasn't recommended but every time it flares up I think it might be getting close to time - I was also told three years ago that I'll probably need knee replacement when I get older. It was funny, I went in for pain in my right knee, and when they did x-rays they said the cartilage in my left knee was WAY worse but it hardly ever gives me issues (knock on wood). It would be a serious hassle to get the right one done because I couldn't drive anywhere.
A friend of mine has needed knee replacement surgery for many years and finally was able to get the first knee done last week - she had to wait until her oldest child was able to drive because she's a single mom and there was no way she could not be driving. Child got their DL in June I think so the replacements have begun!