I waited 7 months, my appointment is in 3 days with a Revision MD. Some people are fine with the metal, maybe not all have the nickel, supposedly there are all ceramic that are stronger, last longer. Flexing 65 degrees for two years and the pain has been horrid. I rode my bike 20 miles a day before surgery, rode horses. I have to lie sideways across the front seat of the car just toe get the knee in. Every single time I get in! I am very active, just do what I can, could not even use a Pottery Wheel at class. The contortion causes a twist and aggravates sciatic. Hope it gets fixed!!! The pain of bone on bone was far preferable as I could bend it at least.