About six years ago, during my tennis years, I had a severe case of arthritis in my left thumb. It was so bad that I could not squeeze a tennis ball in my left hand without severe pain. I could throw the ball up for the serve because the ball only rests in the hand for the toss. Putting the spare ball in my left pocket was impossible from the pain it caused. Consequently, I placed the spare ball in my right pocket with my right hand. It was mildly disconcerting to shift the racket
to the left hand while pocketing the ball in the right pocket, then grasping the racket
with the right for the serve. If a second ball was necessary, again the racket
shift was employed to remove the ball and shift again to get ready for the second serve. I endured this for three years.
Today, I have no arthritic pain in my left thumb. I can squeeze a ball easily, place it in my pocket, remove it, all without any discomfort. However, my right thumb now has arthritic pain. I have taken to doing some tasks with my left hand in order to avoid the pain in the right thumb. We are all aware that arthritis is a buildup of calcium in the joints but what is curious is that it should jump from one thumb to another. Why does it do that? How does it do that?