So far cervical traction is one of the more powerful remedy I found for my syndrome.
I don't have OI, and probably not any brainstem implication in my illness, but mostly cervical spine involvement.
I tried inversion table but got strong nausea. I also felt uncomfortable with the jaw position (projected backward by gravity).
So I moved back to the technic I used to relax my neck muscle. It does a great job to do a correct cervical traction with a weight force of about 6 kg (the weight of the head), which means not far from 10% of body weight.
10% traction was found to be the best weight to relieve pain and improve mobility in spondylosis patients in this modest study: