TOS is very hard to diagnose. It took over 3 years for me and too many Drs.
My PCP and PA hadn't had but one case of it in their 20 years each so they couldnot diagnose me. They sent me out so many times that my PCP finally told me to get a computer and help diagnose myself. It took me a long time to do it but when I did I had a PT'er that agreed with me and she knew exactly what to do to help me. After over 4 years of PT though I finally realized that I needed the surgery.

Don't give up and don't let anyone do any major bone popping until you get a diagnoses. I was made worse by an Osteopathic Dr. She was later ran out of our town.

Like the girls said, no test will rule it in or out. The Nerve Conduction Test to me is the biggest waste of money going. I had 4 and they were all negative.

My thought would be go straight to a Thoracic Outlet Specialist to help diagnose you. Make sure he's good because as you'll learn on here some do more harm then good.

Fibro can cause muscle pain and other problems in the arms and hands but believe me anyone that has both can tell them apart once they get to know them. Try to get in tune with your body and sit down and write exactly what symptoms you are seeing and where the worst pain is. Also what hurts you when you do it such as lifting your arms to look in a cabinet, hang clothes on a clothes line or looking at clothes in a store on a high clothes rack. That is a big issue with TOS'ers.

Hope you find your answers soon.
Ada