Anatomy and pathology of the aging spine.

The vertebral column is a complicated anatomical structure which is composed of the intervertebral discs and the vertebrae. Both components develop special degenerative changes and morphologic features during life. This paper first reviews the anatomical fundamentals and then describes the morphological features of the aging intervertebral disc and the subsequent osseous changes of the vertebral bodies and the zygapophyseal joints. The aging intervertebral disc is characterised by processes which are labeled as intervertebral chondrosis and intervertebral osteochondrosis. Often these processes are combined with typical dislocations of intervertebral disc tissue in an anterior or dorsolateral direction. The well known Schmorl's nodules must also be mentioned in this context. Furthermore calcification and ossification of the intervertebral disc tissue can take place. More severe processes lead to osseous changes of the vertebral bodies. In particular, an osteophytosis of the vertebral bodies can be established. These sturdy osteophytes are able to stiffen the vertebral column. Furthermore the arthrotic changes of the zygapophyseal joints are delineated in this paper. The special appearances of these changes are discussed according to the different and specialised regions of the vertebral column. The advanced degenerative changes of the zygapophyseal and uncovertebral joints of the cervical spine are of essential clinical interest because the compression of the vertebral artery or the narrowing of the intervertebral foramina by these processes may cause severe neurological symptoms. The arthrotic changes of the medial atlantoaxial joint, which lead to the crowned odontoid, and the pseudospondylolisthesis (so called M. Junghanns) of the lumbar spine must also be mentioned. It is the aim of this paper, not only to explain and review the degenerative changes, but to illustrate the anatomy and pathology of the aging spine on the basis of macerated osseous specimens in order to make radiological investigations and pictures more understandable and clear.