The Vertebral Column

=Vertebral Column=

The vertebral column protects the spinal cord, which is part of the peripheral nervous system which supplies nerves to all of the body except the head. The vertebral column allows attachments for the muscles of the back and some of the limbs. It also gives the trunk its flexibility.

The vertebral column is divided into 5 regions - cervical, thoracic, lumbar, sacral and coccyxgeal. Humans typically have 33 vertebrae and 31 spinal nerves emerging from between them. Each region has its own specialisations.

A healthy vertebral column has a distinct curve. At birth, the vertebral column is completely concave - this is the reason that human infants cannot hold up their own head or support their own weight in a sitting position. As the child's muscles grow stronger, the neck muscles pull the neck or cervical vertebrae backwards. The back muscles also gain enough strength to reverse the curve of the lower back or lumbar region, allowing the child to sit.

Source:

Cartmill, Matt, William L. Hylander and James Shafland 1987. Human Structure. Harvard University Press, Cambridge, Massachusetts.