I had a surgical procedure on my patella (tibial tuberosity) to repair the misalignment. That was an epic fail. The bone graft never adhered, broke off after 9 weeks taking a few screws out with it. Emergency surgery to fix that mess left me with no resolution. My other patella needs to be repaired but I'm too afraid to do that procedure again. I found out later that my procedure had not been performed on a patient since the early 60's.