I'm sorry to hear about your spread. I'm dealing with a similar situation now too. My RSD has been in my legs but it recently spread to my wrist and I also had had surgery on that wrist about 10 years ago for a nerve related issue. I think the previous surgery there makes it a "weak spot". My physical therapist explained that to me and it makes sense.

Hoping that you can get some positive results quickly from catching it early!