If you haven't had an MRI yet , it would be good as a check & to rule in or out any obvious structural issues.
TOS doesn't usually show up on MRI either , unless there is a extra cervical rib or some other anomalies that are compromising/impinging the nerve or vascular system in the collarbone, neck, shoulder areas.

I've found some advanced PTs are better at seeing the body as a whole and seeing postural or anomalies that drs miss..
Same for expert chiropractors.

I don't know if you've read on our TOS forum at all , but you can find all the symptoms most of us have.
http://neurotalk.psychcentral.com/showthread.php?t=5618
http://neurotalk.psychcentral.com/forum24.html

In the past quite a few w/ TOS eventually acquired RSD also after many years.