Anatomy Yr-1
Followup cases

31 year old male with neck pain after motor vehicle collision

The inflammation in ankylosing spondylitis is centered on the annulus fibrosis, the outer ring of fibrocartilage in the intervertebral disc. It does not involve the anterior or posterior longitudinal ligaments. Image A again shows the patient's sagittal spine CT with a thin plate of bone uniting the fronts and some of the backs of the vertebra. Image B shows the locations of the posterior longitudinal ligament (blue), the anterior longitudinal ligament (red), the nucleus pulposus of the discs (aqua) and the annulus fibrosis of the discs (yellow). The site of fusion is precisely where the annulus fibrosis is located.

Other inflammatory and degenerative conditions can affect different parts of the spine. In diffuse idiopathic skeletal hyperostosis (DISH), there is dense calcification of the anterior longitudinal ligament, and this can also lead to decreased flexibility and motion of the spine.