Hello. I am new to this forum. I have RSD and it is nice to be able to have someone to relate to this problem. My RSD is in the left arm. The worst part is that horrid burning pain, but the cold and hot are bothersome too. Sometimes when I have a flare up the arm itself will turn its lovely blotchy red and purple color but the back around my shoulder blade will feel like I am on a heat pad. In the beginning I thought I was going crazy until my workers comp doctor showed me the etiology and what is going on. It scares people to look at my arm, let alone touch it because the temp is so cold.