I have symptoms of crps in all 4 limbs. After reading all these helpful posts (thanks!) & consulting with my PM doc, I got the flu shot this weekend in my best arm with a pediatric needle and used a lidocaine patch over the tiny bandage immediately after, and contine to put a fresh lido patch on each day - so far so good. I plan to do the lido patch for 2 weeks.

She told me they could use the ped needle on me as I do not have body fat on my arms (I am pretty petite). Otherwise she said the injection would not go in deep enough due to body fat.
I could not imagine getting the flu on top of all this pain!