Hyaluronan
"After years of experience dealing with back problems, I had assumed my knee pain was from the pain radiating  down my leg and into my knee. I was actually surprised to hear the diagnosis of  severe arthritis . My orthopedic Dr. Did all 3 Orthovisk injections in the same visit. In two weeks the improvement was remarkable! The benefits lasted through 6 to 7 months. Due to changes in insurance my cost jumped from 50$ to 650$( for Orthovisk only to be delivered to Dr office, not including actual procedure) and it's a struggle, but I can definitely say it's worth every penny!"