Interesting idea! I've had some rather nasty auto crashes resulting in cervical spine injury. I also recall several years ago that a doctor referred to the possibility that I have some sort of circulatory entrapment???? He talked about a possible surgery to my collar bone to increase blood flow. Frankly in those pre-PD days, I was young, feeling pretty spunky and really not interested in someone drilling holes in my shoulder so, I retreated and thought nothing more of it other than I always noticed that if I straightened my shoulders too much, I would feel light headed. I adopted the habit of a bit of a slouch and no lightheadedness... problem solved? Not really. Now I look back on all of it and wonder.
I have poked around a bit and come up with this... http://www.nucca.org/
They seem to suggest that specifically trained chiropractors might help. I found only one practicing this in my area (southern California). I haven't checked it out as yet... a bit worried about getting into one more expensive experiment. I think I will at least do an initial visit and will report back.
I did find some claims on the web. Not recommending these folks at all but just for reading...
http://www.ucc-ny.com/conditions-treated/parkinson.html
http://nuccadoctordavis.com/2011/03/...he-upper-neck/