As for the difference between fibro and TOS, it important to know that lots of typing and shallow chest breathing, both common in TOS, will set up trigger points in many spots that are used in the test for fibro. So the doctor has to do a differential diagnosis between triggerpoints/ myofascial pain syndrome and fibro. It's important since trigger points are easier to treat.

I think trigger points are a local phenomema and fibro involves central nervous system effects but I could be wrong.

TOS often causes central nervous system effects as well, so thing can get confusing.