I broke my patella bone playing rugby and took of 30 percent of the knee cap they fixed it back with screws, i was still having alot of trouble 6 months later they did and arthroscipy and found a screw was a bit loose so they cut my knee open to screw it in, after operation knee was alot better , 3 months after which is now it is back to how it was before the operation, going to surgeon agian soon, having screws is my knee is that what would cause the problems through my knee cap?? does it brake away cartlidge ?? i have alot of grinding in my knee again ??