I think one of the posts in the useful sticky thread breaks down the % of occurrence for neuro, vascular and such.
I can't recall what they are off hand.

With vascular it would need to be sorted out between venous vs arterial - supposedly venous is more likely to produce possible clots, due to the blood pooling and just not getting circulated back to oxygenate.

That article doesn't really account for mild /moderate RSI/TOS types that may be due to adhesions or sticky fascia.
Those can be a mix of sx depending on where & what is being affected = "stuck"

I don't know how you feel about chiropractic??
But it may be something to look into, getting some evaluations by a few expert DCs. And some that do the upper cervical (atlas axis) adjusting also, due to all the falls and accidents.
see this for more info -
http://www.upcspine.com/self.htm
www.upcspine.com

If there are misalignments, those really should be addressed before trying to more forward. It's like trying to build a house on a crooked or broken foundation.

And unfortunately most MDs generally will not advise or suggest any DC care..so it's is up to us to sort it all out.
But I had the best results from a very good chiro, that uses PT type modalities as well as adjustments.

Out of a total of about 8 PTs that treated me - I found only 2 that were exceptionally good.

So for PTs or DCs you have to search out the really good ones with advanced training. Don't settle for a standard PT plan that they do for almost everyone that walks in the door with neck/arm pain.