Hypertrophy of the neck and surrounding muscles can be a factor towards TOS type of symptoms.
Do or did you focus on a high development of those muscles?
Hypermobile joints are prone to RSI and other problems...

As mentioned finger, hand, arm, shoulder, neck and upper back pain are the primary symptoms of TOS .

You could have full body sticky fascia or maybe even scar tissue or something totally different??
I think a full work up as suggested would be a good idea.

Maybe a change to yoga and stretching and walking might be something to try when you are on the mend again.