Superior view
    Lumbar, Cervical

The vertebral foramen is of functional importance since it provides for the passage of the spinal cord and the meninges.  This foramen gets progressively smaller as one moves inferiorly.  The large size is not necessary in the inferior regions because the spinal cord becomes smaller in diameter (tapers like a carrot) as it moves inferiorly.  This occurs because the spinal nerves are leaving it at each intervertebral foramen.  The spinal cord normally ends in the adult human at the level of the inferior edge of L1 body, although it may end close to T12 body or as far inferiorly as L2 body.  In an infant it usually terminates in the area of L3 or L4.  The foramen is triangular in shape for the cervical vertebrae.  The thoracic vertebrae have a circular vertebral foramen.  The lumbar vertebrae have triangular foramina.  Together the vertebral foramina form the vertebral canal.

COPYRIGHT 2007 by William C. Johnson II
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