In the symptoms you listed, to me you have RSD. My foot turns black and blue also and comes and goes. I have the burning pain and sensitive to touch. If you have had 3 dr.'s tell you its rsd then you got rsd.

On the other side, it is possible to have TOS with RSD so don't rule out the possiblity of having both.

It is very frustrating I know to have some say you have it while others disagree. My therapist kept sending notes to my dr. stating something was not right she could not even touch my foot without me crying. (she was unfamiliar with rsd and at this point I had never heard of it) He ignored it. It wasn't until I saw a podiatrist did I get the dx. of rsd.