I actually got this trigger point ball set to get in between the shoulder blades, which is where alot of my neck pain originates.
https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1
I use both the single and double balls depending on what I want to achieve. With the double set, I go to a wall and position the balls so that one is on each side of the spine and roll against the wall. If you cross your arms over your chest you can get in there a little better, too. If you don't like the idea of a double ball just use the single trigger point ball, which is a really nice one with small bumps to really get those muscles good. You can adjust the intensity by pressing against the wall harder or softer. Either way, it is really good for getting into those muscles, better than a foam roller. I still use a foam roller for lower body, but for the back and shoulders I use these.