The popping sound is created by the shifting of the lubricating fluid and gas in a spinal joint. Think of it as the release of pressure that accompanies the opening of a can of soda or a bottle of champagne.
Few. In fact, most side effects are positive effects!
Certain critics of chiropractic care will raise the issue of vertebral arterial dissection and the complications of stroke associated with getting a neck adjustment. Even after an extensive review of the scientific literature, only a handful of documented cases of this phenomenon can be found among many millions of chiropractic patients. Moreover, many of these instances are the result of neck manipulations delivered by poorly trained non-chiropractors.