Hi, I'm Julie.
I had to look up Klippel-Feil Syndrome, and I'm sorry, it must cause you much pain. I have cervical dystonia with tonus. Mine is intermittent. I have systemic lupus and trigeminal neuralgia. When I have a tn attack with all 3 branches of the trigeminal nerve, I also experience cervical dystonia with tonus. Not only is it surreal and the most painful horrific condition I've ever endured, I've often thought my neck would become permanently paralyzed that way and it's terrifying.
To complicate things, perhaps it's the perfect storm of symptoms that caused the dystonia in the first place, my docs disagree, but I also have pretty severe osteoarthritis in my neck. Since I already experience cranial neuropathies, (TN, geniculate neuralgia, problems with distortions in taste and smell, Bells Palsy twice), I found information that cranial nerve 11 also called the auxilliary nerve controls the muscles in the cervical area that can cause cervical dystonia. I'll share my info/research with you if you like.
Now, on to what I do for the treatment. I take anti-seizure meds for the tn and it helps somewhat with the dystonia. Since my problem with the tonus is intermittent, the neck pain I have most of the time is from herniated discs and bony spurs (OA) cervical C2 to C4) My pain mgmt doc says its a mess back there. My rheumie says my peripheral neuropathy and cranial neuropathies likely come from inflammatory process of lupus attacking the myelin sheath on my nerves causing the neuropathies.
Anyway, my pain mgmt doc gives me rfa's and they are LIFESAVERS. I used to have cortisone shots back there. At one time the pain in my neck was so bad I had a radiculopathy with it all the way down my left arm and I was hunched over in pain. Yelling. I was laying on BURNING heat pads to keep from screaming. I get radio frequency ablations every 8 months on both sides. It gives me back quality and movement in my neck. I have other pain to worry about and a family and some work and there's no way I can handle everything. It's a huge help.
Here's a snippet I put together about cervical dystonia and cranial nerves: Accordingly, trigeminal neuralgia as a result of disc herniation, disc bulging, spondylolisthesis and spinal kyphosis or slippage, amongst other conditions, can be responsible for serious problems with the innervation of the face, jaw, and pharynx. Facial pain, jaw pain, neck pain, problems with chewing and swallowing, a sensation of a lump in the throat, and muscular spasms in the face, jaw, and neck can all result from compression of the cervical spinal nerves.
Cervical Spinal Nerves
The hypopharynx’s uppermost point is at the hyoid bone, which lies at approximately the same level as the 4th-6th cervical vertebrae. The pharynx is innervated by a number of nerves with their roots in the cervical spine. Damage to these nerve pathways can result in problems with the correct functioning of all three sections with ramifications for proper control of the separation of the larynx and oesophagus. Faults in innervation, both motor and sensory, in this area may prevent the two pathways functioning properly.
I hope that helps. btw I found your post because I have google looking for blogs on cervical dystonia for me. Theres hardly any of them and when I find someone like you I get excited!

Much Love, Julie