My PT has helped me with the sharp shooting pains by manual "flossing" of the arm, traps and shoulder muscles and nerves.
I would normaly press on my palm and thumb to relieve the pain.
Like a pressure point type of thing.

Opening up the brachial plexus by laying on the floor practicing trap exercises and laying on a styrofoam roll to open up has also contributed to less of constant pain.
I find when i use the compooper, try to work on mylegal paper work, use my hands for normal daily function it flares up again.
Frustrating as it is I avoid until I have to.

So the exercises are a must throughout the day.
And of course I use ice, valium for the calming of the nerve pain and lidoderm patches are now place on my upper arm inside. Finding the placement has been the key.
XXOO