I’m not sure if they mentioned, but did the report (MRI most likely) had anything about CXA or “clivoaxial angle”? Now that I think, the whiplash could have affected how the skull sits on the spine (basically cranium’s position on the first vertebrae, C1). That’s where significant amount of flexion occurs (I posted it earlier on the other thread about how much statistically the C0/C1 segment flexes/extends: List of my favourite resources on YouTube to learn anatomy - #76 by vdm ). I am not sure (yet) if that’s the mechanism, but I suspect that in some cases this craniocervical junction gets affected and “stuck” (or partially stuck losing range of motion). Maybe, just maybe, in your case it got “stuck” in the “flexed” position and that’s why the normal length styloid processes could now compress the IJVs.
As for the chiropractors… It’s everyone’s personal choice. Some swear by them, and claim they saved their lives. I personally am extremely sceptic as there are enough of horror stories when people get strokes, develop craniocervical instabilities and other life-damaging conditions. One of the things to be aware of, chiropractic manipulations can cause not only vertebral artery dissections (in typical “unfortunate” cases), but also internal carotid dissections (in cases with elongated styloid processes).
Perhaps nobody had run a study on possible IJV damage caused by chiros, as that’s very likely is way less symptomatic than arterial dissection, thus any weird symptoms after the manipulations could be brushed under the carpet by saying “detoxification” or some other obscurity.
Ah, what’s so special about CXA:
- Clivo-axial angle - MEpedia
- https://www.physio-pedia.com/Cervical_Instability
- Normal range of clivoaxial angle in adults using flexion and extension cervical magnetic resonance imaging scans - PMC
- Utility of the clivo-axial angle in assessing brainstem deformity: pilot study and literature review - PMC
Basically it is the angle between one specific landmark in skull and the odontoid (part of the second vertebra, C2). It can help to indicate potential brainstem compression, happening either due to injury or craniocervical instability.
Also by comparing how much CXA changes between flexion/extension (often can be measured on plane x-rays, though flexion/extension MRI in upright position is much more accurate), one can predict whether the C0-C1 junction is properly working, too loose, too tight etc.