Most people seem to have a positive report on the surgery; mine is not so positive. My intention is not to put you off but just give you the other side of the coin.
My injury comes from an accident with a play park swing-boat when I was 7, in Battersea Park. After several operations: cartilage, loose-body, bits of tidying up, etc, and because I found it painful to stand upon for more than 2 hours, my wife persuaded me to go for the full replacement op. I now regret it.
Now I find I can't walk even as far as I could before, I can't cycle more than a few hundred yards because it feels like a rusty hinge - you know that feeling you get when someone scrapes their fingernails down a blackboard…
I used to cycle all over the place before - - flogged the Cannondale on eBay after the op.
Upon a surgical review, the surgeon told me that, when they fit the replacement bits of plastic and metal, they remove the ligament that passes through the joint. Well, great! That's where the pain was coming from anyway. They could have just operated upon that and not left me with the rusty hinge.
As I said, I don't want to scare you off; there's a very good chance that it will be a big improvement for you but, do bear in mind that it has to be re-done at sometime in the future too - all of that digging about to remove the old one - and through scar tissue. Not fun !
I'd mostly got used to the painful times before the op; I'd just sit down for ten minutes, and Diclofenac used to help when it got bad. I still have to use the Diclofenacs from time to time because I still get pain and, I have to say that, if I could choose to have my pre-op state, I would.
Sincerely - all the best of luck.