What Causes Sharp Pain In Shoulder Blades Radiating To The Back Of Arm?

The muscles by my shoulder blades have sharp pains and it runs down the back of arm and into hands and fingers. If I use my hands to pick something up, lift my arms, or even when I lie down and sleep,it feels as tho the circulation is cut off to my arm and hands. In the morning my hands are swollen and I cannot open my hand all the way and I can t use them bc i can t grip anything. I use meth.is it dehydration or nerve dage?