I have the RSD/TOS combo platter.
Dr Schwartzman called it a "very common injury" , I was "T-boned in the drivers door by a Semi, in my pickup. I braced, and took the hit on my elbow.

Since Jefferson is a university hospital, and at that moment I was the only one in who had RSD/TOS, he would parade a new group of students in to see me every twice a day.

A simple test for TOS, is this.
Stand in front of a lighted mirror, (your bathroom will do).
Put your hands up, as if someone says "Stick em up".
Now, this is tough to describe, but you hafto push or roll your shoulders as far back as you can.
Look at the palms of your hands in the mirror.
If you have another person available, they can look, and also feel your wrists for a pulse.

If you have a "good" case of TOS, this position will stop the pulse @ your wrists.
Your hands will go numb due to nerve impingement. They'll also turn white, due to lack of blood flow. (that's what you're looking for).
Let your hands down, and you'll see the color return.

You see, TOS is a series of injuries that closes up the Thoracic Outlet, and squeezes the nerves and blood supply to your head, neck and arms.

A normal sitting position for someone with this ailment, is to roll, or curl the shoulders foward, and let your hands lay in your lap.

I was a master plumber when I got injured, and muscular. Dr S told me that I would loose all that, especially the sheath of muscles that covered my shoulders/blades.
Back then, you couldn't feel my shoulder blades, now, they stick out. I can easily feel them.

Again,
I'm not a doctor, this is my "simple" education from watching my doctors.
You need a GOOD Neurologist, and Good hand / arm surgeon / specialist, or a thoracic surgeon to diagnose this. (It seems to me, that they should be getting much better at it these days).

The numb arms, fingers, the HEADACHES, the absolute DEAD ARMS in the middle of the night...
And, of course the pain. I hope you don't have it. If you do, don't be quick about any surgery....
The muscle atrophy, will eventually give you room.
And, another side effect you'll notice if you have TOS, if you use your arms for anything that requires strength, say push ups, or pull ups. It would flare you right up! Possibly trigger a headache.

I have a nightmare story about a test a thoracic surgeon put me through once, before I met Dr S.
But, due to my TOS, I can't write much more at the moment without a break.

BE well,

Pete
ASB