There's still a lot you can do. Besides upper body, there's a whole world of core work you can do. There are people on this board with severe scoliosis, people who weigh 400 pounds, people who used to be in wheelchairs who are still managing to find a way to exercise and do what they can, how they can. I know I am a hardass about this (it is nothing personal, Barb), but people with perfectly functional bodies who are not taking advantage of such a GIFT really sticks in my craw.
"Let food be thy medicine and medicine be thy food." -- Hippocrates