Hyaluronan
"Had surgery on both knees then the doctor said I need knee replacement.  That was 10 years ago. When knees started to hurt I started on Synvisc one for a few years. Than my insurance wanted me to use a generic version gel one. Both of these drugs worked fine for my bone on bone for both knees. Than my insurance stopped paying for any more shots. I looked for another treatment plan that would cover my shots. Found another doctor was going to give me orthovisc. I started the shots in June. The shots are given 3 times rather than once by the other drugs but still last only 6 months. My next group of shots are for December.  This drug works but takes almost 6 weeks for all of 3 shots . Great stuff does work hope my insurance pays for it."