Unfortunately, if left untreated, it can go up the arm to the elbow, and into the shoulder.. just like regular tendonitis.

You can have arthritis worse in one joint, than the whole body, especially if that joint had been injured (or broken bone) in the past.

Yes any white food except cauliflower, just about. Rice, enriched breads, rice, grits, white pastas, etc. Also, the nightshade foods potato, eggplant etc. You can get more info at the arthritis website.