Jon, I don't envy you in having knee problems. Having said that, I will also say that in my line-up of "older" friends, that knee replacement seems to be very common. For the most part my friends are getting along fine after the process. I know that it will never be as good as the good Lord made for you at the start, but it is getting so they have the procedure down pretty good. I hope the injection works good for you and it will give you relief and mobility for a long long time. However if it does not there is a pretty good option.