I have had this insanely effed up shoulder for a while, especially after changing desks. And then I started to get a sore hip. I got in my head one day that I needed a sitting position that would let my arms/shoulders hang in a more relaxed state, and not scrunch up my spine so much. I settled on one of those giant inflated yoga/exercise balls.
And you know what? The hip soreness is gone, and my shoulder is starting to get better.
IANAD but TL,DR: if your normal coding / sitting position has your arms in t-rex position a lot of the time, you are probably causing neurological damage. Stop.
Btw: like winter tires, it helps if your ball is ever so mildly deflated, like so:
, - ~ ~ ~ - , , ' ' , , , , , , , , , , , , , , , , , ' ' - , _ _ _ , '
Give it a shot!