Chuck,
I too have been having muscle spasms mainly in the right side of my neck and moderate to severe pain in my neck, shoulders and upper back. My drs.@ MD.Anderson said it is a result of radiation. They tried botox injections but not much relief. I am currently taking a muscle relaxer Zanaflex and physical therapy 3 x week.I use a TENS unit at home and so far all of this has helped tremendously. Hope you get relief soon!