Head and cervical spine turned to the side just prior to rear end collision. Forces exerted on spine from whiplash type injury of this nature can cause facet joints to collide with sufficient energy to damage the joint cartilage. Once the cartilage is damaged it can continue to degrade as the facet joint move against each other. Eventually the cartilage will erode away leaving the affected facet joints unprotected. Chronic neck pain develops from the resultant bone on bone contact as the facet joint continues to degrade. To help manage the pain the physician must block the pathway from the facet joint to the spinal cord through injections and ultimately, radiofrequency rhizotomies.