The spine is the axial organ of our body and consists of 7 cervical vertebrae(C) from the skull downwards, 12 thoracic vertebrae(T) in the breast and lung area, 5 lumbar vertebrae(L) at the base of the spine behind the abdomen attached to the sacral bone or pelvis, and lastly the coccyx – the remnant of our prehistoric ‘tails’.
Between the vertebrae (beginning at the level C2/3) there are intervertebral cartilaginous discs.
The whole static load of the body is on the spine, increasing from the skull down to the pelvis, which is why the vertebrae and the intervertebral discs also increase in size in the same direction. The normal shape is a 1½ shallow “S”. The curvature of the cervical and lumbar spine is to the front, while that of the thoracic spine is to the back.
The cranio-cervical junction between head and first and second vertebra is quite different to the other parts of he spine. In these joints and vertebrae most of the motion of the head is accomplished. In the sacral and coccyx bone there are no intervertebral discs.