With regards to the original case reported on this post (msk101's patient) I think the reality needs to be accepted that you are chasing a diagnosis that will not be found. From your reports there is every indication that if there was a mild initial neurological lesion evidence of this does not exist or can no longer be seen. The initial "mechanism of injury" (if it can be called that) does not remotely fit with the patient's subsequent symptoms, if for no other reason than it was 2 days following the mobilization before symptoms started. Just because the patient attributed her PT session as the cause of her dizziness does not make it so, and given the descriptions you have provided it looks like no practitioner she has seen has told her this. The fact that mobilizations at C56 on one side in essentially one direction reproduces her symptoms (mildly, as I understood it anyways) sounds alot more like a "learned response" rather than a comparable sign. It just doesn't fit with anything else.

Her severe anxiety, cervical hypersensitivity and hyper-vigilance (desperately aware of the slightest onset of her symptoms, and extremely protective of herself when experiencing them) vastly more lend themselves towards the onset of what would usually be called a pain disorder along the lines of what you would see in a chronic pain management population, although in this case it is a "lightheadness disorder". You don't mention regular falls or true loss of balance despite her residual symptoms, which likely indicates this patient is capable of more than she realizes (I admit I am assuming a significantly level of disability given the way you describe her overall status).

I am genuinely sorry this patient continues to experience these symptoms, but she (and yourself as her rehabilitative practitioner) need to target the obvious secondary symptoms that in all likelihood are magnifying her primary symptoms. Talk to anyone who works in chronic pain management or disability, and they will provide for you countless examples of patient's secondary issues greatly magnifying their primary problem.

At best there was a minor neurological incident that symptomatically did not fully resolve and they can do nothing about medically 14 months after the fact. At worst she had some transient symptoms that she latched on to and now uses to define her existence.

The best treatment you can do for her is stopping investigating (all it's doing is wasting time and over-medicalizing the situation), get her to see a counsellor/psychologist to teach her how to work herself out from her anxious and hyper-vigilant state, and get her to see a PT with a specialization in balance and vestibular disorders so she can re-build her balance (or confidence in her balance). That way she can get on with her life instead of waiting for a magic answer and solution that is unlikely to come.

Anyone else out there think this?