You should really seek a second opinion before having such major surgery. I'm postponing mine as long as possible. I just had a series of Synvisc injections and I am now pain-free. It won't last forever, but it can be effective for a year. Then it can be repeated for several years.
You want to postpone this surgery as long as possible because if you do it too young, you'll wear down the new artificial knee and have to replace it -- which is a very severe surgery. You don't ever want to replace the artificial knee. That's why many orthopedic surgeons won't even do knee replacements on patients under 65. People over 65 are much less likely to wear out the artificial knee. Once the artificial knee is in place, they've removed so much bone to install it that replacing it is very dubious.
It's probably not an issue of whether you need to have surgery or not, more likely, it's a question of when. The longer you can postpone it, the better. Knee surgery has hugely improved even in the past eight years. The longer you can wait, the better still the techniques and equipment will be.
Please read this book on considering knee surgery: What Your Doctor May Not Tell You About Knee Pain and Surgery by Ronald Grelsamer, M.D.
http://www.amazon.com/exec/obidos/t...=glance&s=books
I've just finished reading seven books on knee problems. This one's the best in general and less opinionated than the first I gave you: The Knee Crisis Handbook by Bruce Halpern, M. D.
http://www.amazon.com/exec/obidos/A...6201813-7124601
You have my sympathy for your pain and reduced mobility. I've been going through it since October.
Oh, here's another excellent book, this one's on knee arthritis, despite the title: Wear and Tear by Bob Arnot, M.D.
http://www.amazon.com/exec/obidos/t...=glance&s=books
Again, please know that you're not alone in this and that others understand what you're going through.