The spine or vertebral column is the main supporting structure in the human body. Both upper and lower limbs are connected to it through a complex series of joints. The ribs are attached to the backbone in the rear of the chest wall so that contraction of muscles allows for coordinated expansion of the chest and breathing. Muscles, ligaments, and tendons connect various portions of the backbone to one another along with other structures, allowing a broad range of movements. In order to see the structure of the vertebral column, one may do no better than look at the work of Andreas Vesalius.
He was an anatomist born in Brussels and was professor at Leuven and Padua. He produced a spectacular book in 1543 entitled De Humani Corporis Fabrica – The Structure of the Human Body. This was a brand new departure in the study of anatomy, as it was based entirely on dissection. This volume is remarkable for its illustrations by Italian draughtsmen. There’s a large series of plates that illustrate anatomy of human body in superb detail. Among the joys of those drawings is the sense of emotion in the positions of the subjects. A lot of the plates includes a background against which the subject is posed and the separated plates can be joined together to give a panoramic view of Tuscany in the sixteenth century.
The backbone has to carry a heavy load. At any level it’s the vertebral column which is principally accountable for transmitting the weight of the body above and any loads being lifted or carried. When muscles contract to produce movements or stabilize joints, there’s frequently additional stress on the vertebral column. The backbone is, however, remarkably flexible. It can bend forwards, backwards, and sideways and it could twist. Frequently these movements are undertaken in complex combinations and with load bearing at the same time. The spinal cord emerges from the base of the brain and passes downwards throughout the vertebral column.
It subdivides into nerve roots which emerge through spaces between the vertebrae. These nerves will reach every body tissue. They carry info from the tissues to the spinal cord and after that to the brain, allowing perception of sensations. In turn messages from the brain are carried back down the spinal cord and along the nerves to activate muscles and produce movements. The spinal cord is an extremely delicate and complicated structure. It’s protected against harm by lying inside a column of bony arches in the rear of the backbone. This is known as the vertebral canal. The nerve roots separate from the spinal cord and pass obliquely downwards to emerge from the vertebral canal through openings known as holes intervertebral.