Superior view

The body (centrum) of the vertebra is the surface that bears most of the weight of the structures superior to it.  Since we walk on two appendages, the weight progressively gets greater as one moves from the cervical to the lumbar regions.  Therefore, it makes sense that the superior vertebrae have much smaller bodies and that the size of the body progressively gets larger as we move inferiorly.  Compare the size of the body of the lumbar vertebra on the left with the size of the body of the cervical vertebra on the right.  The shape of the bodies change as well as the size.  The body of a cervical vertebra is wider laterally than it is in the anteroposterior direction giving it an oval appearance.  The thoracic bodies tend to be more heart-shaped and they have depressions where the demifacets are.  Lumbar vertebrae have a kidney or oval shaped body.  The depth (thickness) of the lumbar vertebrae is greater than the superior areas.

COPYRIGHT 2007 by William C. Johnson II
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