Milou,
My MDs didn't get into the TOS thing at all, they got hung up with diagnosis's of multiple repetitive strain injuries . My symptoms moved around a lot{ nearly every RSI except carpal tunnel}.

I finally found a very good chiropractor and then 2 other advanced PTs that did the comprehensive positional testing - to rule in or out TOS and /or c spine problems.

PS - I forgot to add our useful stickys link for you , lots of info to help you sort some of it out -
http://neurotalk.psychcentral.com/thread84.html