I also suggest trying the Infrared Heating pad - the heat & healing action goes deeper than regular heating pads. I have 1 from 2004 and it still works great, but got a larger size in the jade disk style for one the back of the recliner.
I got mine for muscle, RSI,CMP pain, but dh & son use it also..for general aches & pains.

http://www.amazon.com/s/ref=sr_nr_n_...nid=2941120011

The Thermotex products have rectangle flat sections, somewhat padded but not nearly as soft/flexible as the smaller circular disk pads in the UTK Heating Pad with Natural Jade Stones.

If you can request or find a practitioner that has a low level laser - some chiros have them - more so than PTs or MDs..
It might be worth trying a few sessions of LLLT for pain relief.
I can say it worked very well & quickly for my various pain areas.
I can't say if it will help for the RSD part though.

If your RSD isn't in the shoulder area, maybe try some of the KT tape/kinesio taping?
https://www.kinesiotaping.com/
There are pretty good videos on how to apply it, but having a pro do it a few times first is the best. It lasts about 4 days,

I recently had a shoulder strain or small tear and my chiro did some Gua Sha and then taped my shoulder. I also used the infrared heating pad a lot along with it.
https://www.youtube.com/watch?v=FJuuIcI-4Es