There is a special x-ray series that takes a live moving image of the neck as you move the head. It looks at the stability between C-1 and occiput (base of skull)

Look up myoworx.com in Guelph. Well worth checking in with your condition.

The Ontario NeuroTrauma Foundation may also be able to direct you to help.

Nobody will see the instability with CTs or MRIs. A very skilled physical therapist may be able to help you with some gentle traction and mobilization.

An upper cervical chiro may help

BUT, most of the treatment is self-treatment. Sleeping in straight posture with no head lift. FOR MONTHS AND MONTHS. Strained ligaments take a long time to heal. Some neck strengthening exercises, static exercise, NOT range of motion exercises may be in order.