I've had a patient that I worked on for some time with a very tight trap and levator scap on the right side. I've done injections, joint and muscle work with only temporary results. I eventually understood why I wasn't getting anywhere when he said it was tugging considerably to the right. I think the only reason his head wasn't sidebent to right was because of all the work I did. I finally became clear he had cervical dystonia and I have now botox'ed all the tight effected muscles. I had two other cases that appeared hopeless but had a slight right sidebend tattle-tailing their cervical dystonia. One is almost off his opioids since he has had botox shots. I'm not saying that is your problem but it might apply to one of your readers and they should take note.