THE SPINE

Anatomy > The Vertebrae


Each individual vertebra is made up of several parts.

The vertebral body is the main weight bearing area

The lamina are flat plates of bone which connect, via the pedicles, to the vertebral body, forming the spinal canal and protecting the spinal cord and cauda equina.

The spinous process is a section of bone which protrudes from the back of the vertebrae. This is the knobbly bone you can feel if you run your hand down your spine. Muscles and ligaments necessary for movement and stability of the spine attach to this process

The transverse processes extend outwards from the sides of each vertebra. These also provide attachments for muscles and ligaments.

Each vertebra also has four facet joints, two at the top and two at the bottom. These interlock with the vertebrae above and below to provide a stable, yet mobile spine.

The precise size and structure of each of our vertebra varies according to its location.

Cervical vertebrae are the smallest of the vertebrae The top two (C1 and C2) are very special in size, shape and function. The topmost vertebra is also known as the Atlas (after the Greek god who held the world on his shoulders). The Atlas supports the skull and allows us to nod our heads. Underneath the Atlas is the Axis, joined by a blunt tooth-like protrusion known as the odontoid process. It is this special joint which allows us to rotate our head from side to side.

The thoracic vertebrae are somewhat larger than the cervical and increase in size from T1 through to T12. The ribs are attached to T1 to T10, allowing for a much more limited range of motion for this section of the spine (which accounts for the rarity of degenerative disease in this area).

The lumbar vertebrae are larger still, as these are the major weight bearing structures of the spinal column.