I would suggest you see a rheumatologist if you haven't already to rule out arthritis. I have had the same problem for many, many years and after my rheumatologist sent me for an MRI, they found degenerative changes caused by the arthritis.
You could also consult with an orthopedist who will also order an MRI.
A neurologist is another specialist who could most likely help you find a diagnosis.
Just do me.........and yourself, one massive favor and if any of these doctors recommend surgery, GET A SECOND AND EVEN A THIRD OPINION!!!!!!! Often a good sports physical therapist can help..........even if there is bone damage. They can help you build up the muscles in your neck and shoulder that CAN possibly fix or at least, lessen the frequency and pain of this condition.
In the meantime, start doing some VERY gentle Yoga that focuses on the neck...........but NEVER force your neck beyond your pain threshold.
I hope you find the help you need. I know how lousy this is to live with, but there IS help out there. You just gotta find it!
RubyWitch