I previously was an mid-pack endurance athelete accomplishing many marathons and half ironmans. A year and a half ago I did a downhill marathon and since then my right knee is having a lot of problems. I finally could not run at all, so I saw an orthopedic surgeon who recommended a partial knee replacement (Patella) and a fix to a torn meniscus. I did the menisus repair, but want to avoid the partial knee replacement with all my being. I received the same diagnosis 8-10 years ago, so I am sure there are issues. That being said, I can't do any running or climbing on the bike, as that causes a lot of knee pain when I try to sleep. Even without exercising it is terrible at night. The pain is in the inner, lower area of the knee.  Dr. Marv Anderson is my friend, and he recommended that I contact you for a consultation to see if there are alternatives to think about. I have an MRI from last spring available. Thank you!