bad knees? bone on bone!

I'm trying to get a "feel" from all cyclist(s) with bad knees and the quality of training and successes in competition.
Background (very brief):
I'm 36 y/o and an experienced road cyclist with some competitive years (cat 4). I've had 4 knee surgeries on my right knee (meniscus damage only) and 2 knee surgeries on my left (same thing). Right knee has been "bone on bone" for a couple of years. Rigth now, I'm limited to century and double century rides (with pain that I've learned to live with). I'll never do anything but cycle so getting of the bike is NOT an option!!
I NEED to know, how many of fellow cyclist have similar problems and to what degree. A basic question of curiosity: How do "you" cycle and are there any secrets to "YOUR" success? Also, suggestions would be helpful in regards to training.
I'm familiar with current therapies (i.e., prolotherapy). If there is any suggestions please let me know.

Thank you all
Jerry

I have one knee with a lot of problems. Fortunately I still have some meniscus left but my PCL is bad off so I have a lot of laxity which beats up the menisci.
I find doing good physical therapy to train my "propreoceptors" helps a lot and allows me to ride longer before the pain starts. That keeps the joint aligned better and delays the pain.
I don't like the pain because I know when I'm feeling it, I'm causing erosion in there and making osteoarthritis and knee replacement much more likely.

Ibuprofen helps a lot too!

Tim

Centuries and double centuries? I can see that from the point of view of reduced force for pedaling, but it seems like that would be counteracted by the very long distance. They say the ultras are ok?

My knees ache at times but I have no major injury. The aches come from excessive use over the years. Far worse is the pain I get in my left hip that can ache to the bone.
I try to take care of my knees by standing when I climb and being very careful over seat adjustment. I find my leg has to stop a little short of lock-out on the downstroke to take stress off the knee.
I think it's very important to have easy days so I try not to climb all the time. I also think you should be aware of your knees while on a ride. If you listen to them you can kind of sense when they are being stressed by a gear ratio. Good gearing should take stress off the knee. Bad gearing places too much strain on the joint.
I did find leg extensions good for my own knee problems years ago. The chiropracter Dr Franco Columbo also vouched for leg-extensions in certain cases of injury.

I'm much older with a long history of knee problems(not much cartilage and only one kneecap left). Only medical solution is knee replacement and I'm not ready for that. I have been able to get back into cycling after having to quit a few years ago due to pain by the use of:Chondroitin Sulfate, MSM in large doses and the use of DMSO.

Bob Westgate