STRUCTURE AND DEVELOPMENT OF THE SPINE

That part of the human body loosely referred to as the back is a complex arrangement of bones, joints, muscles and fasciae morphologically and physiologically the same as like tissues elsewhere in the organism. The bones are arranged in column and with the other tissues are segmentally innervated and nourished. In addition to these common tissues there is, between each two presacral vertebral bodies, a disk of specialized fibrous tissue peculiar to the midline of the body. These are attached to the cartilaginous plates of adjacent vertebral bodies and are pulpified centrally to serve as comblition shock absorbers and rocking joints. In addition to the amphiarthroses or half joints formed by the disks, each vertebra forms true joints with the segments above and below it by paired articular processes, the inferior pair hooking down behind the superior pair of the segment below. These are true diarthroses having capsules, synovial linings