I have had bi-lateral rib resections for TOS so both arms and hands are affected. I thought the muscle spasms were bad when I just had TOS, RSD brings even more spasms to my hands. Years ago I was sent to the ER by ambulance, and my left arm and hand were completely locked up. The ER Dr thought he could move my arm, but he couldn't make it move one inch. Even gave me a strong sedative to help release it. My hand was curled in a fist and about 5 hours later it started letting go. My hands cramp up every day and it hurts like hell. Whenever I try to cook or use them at all, it does the same thing. I hope yours gets better, not something that a person can take for long periods of time.
Stephen