I'm on 20 mg. Prednisone (tapered down from 40 mg. for GCA). I had a dexascan lately without any problems. Did you always have problems with your back? I ask because I have arm and shoulder pain from an old injury that never goes away. If the pain doesn't go away, might be best to let your doctor know. PMR is treated with prednisone at a lower dose than Giant Cell Arteritis, which requires a higher dose. Do you have any head pains, eye pains or difficulty seeing, scalp tenderness, difficulty chewing? If so, let your doctor know immediately. I have osteoporosis, and my upper back sometimes aches, especially after working on the computer a while. I've found that lying flat on a hard surface helps take the pain away (a spinal alignment exercise from Sara Meeks). All the Best.