A term referring to any disorder of the The main nerve trunk running down the spinal canal and connecting the individual’s mind and consciousness to the rest of his or her body. It is about the size of a person’s little finger, in diameter. It cannot repair itself if damaged.. Derived from the Greek word “myelos”, meaning “marrow”, if reflects the fact that ancient anatomists viewed the articulated The individual bones that we call vertebrae, when joined together by several ligaments, make of the spinal, or vertebral column. in the same way as they saw the long bones, as having a “marrow” within it. The blood-forming marrow of the long bones is, of course, very much different in function from the “marrow” of the The individual bones that comprise the spinal column are made up of a weight-bearing “body” and other components which, together, form a ring of bone, behind the body. These individual vertebrae, joined together as the spinal column, therefore, create a canal running down the entire length of the spine..