What Is The Treatment For Painful And Swollen Knee?

I have had pain and significant swelling in the right knee for over a year. So far the ortho. has "drained" the knee and then injected cortisone. The cortisone takes much of the pain away for a couple months, but it eventually comes back. Due to my spinal cord stimulator, he has recommended a CT arthrogram. I am thinking that if I can get the knee drained and cortisone injected every few months that there is no reason to make a big deal out of this. Am I being naive about the long term effects of continuing this approach of pain/swelling management?