It all sounds very familiar.

Sounds like the car crash set it all in motion.
You might want to look into filing a claim, I don't know the statute of limitations for car accidents, but if you have the medical records showing the continued & increasing problems...

but back to your symptoms-

There are what is called double & triple crush syndromes- that is TOS or TOS like injury plus symptoms at the carpal tunnel or the cubital tunnel - some have one of those and some will have both.

So it sounds like since the surgery for those didn't fix anything, that the focus needs to be in the neck/collarbone/top rib areas, possibly the pec minor also.

I think you need to seek out a doc with much more knowledge of TOS and brachial plexus injuries.

Does your neck, shoulders and upper back seem to be sore, strained and tight feeling quite often?

The tightness can travel down the arms and cause pulling on the joints, I get a tight or jammed feeling in my wrist when I've done too much without resting/stretching. Feels like it needs to pop or be pulled to release it.

But if you think it is arthritis that can be checked by xray usually.
The joints would probably be swollen if arthritis also.

check out stickys up above the thread list -

it is really helpful to look thru our useful stickys -
post # 1 has many info sites and help sites listed - kind of a crash course in TOS.
http://neurotalk.psychcentral.com/thread84.html

drs & PT listings is there.
http://neurotalk.psychcentral.com/thread135.html