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Anatomy of the Vertebral Column


  • It forms the central axis of the skeleton.
  • Is centered in the midsagittal plane of the posterior trunk.


  1. It encloses and protects the spinal cord.
  2. Acts as support for the trunk.
  3. It supports the skull superiorly.
  4. Attachment of ribs laterally.

v   In early life the vertebral column normally consists of 33 small, irregular bones which we called vertebrae.


  1. 7 Cervical Vertebrae – Upper seven vertebrae that occupy the region of the neck.
  2. 12 Thoracic Vertebrae – It lies in the dorsal portion of the thorax.
  3. 5 Lumbar Vertebrae – Occupying the region of the loin or lumbus.
  4. 5 Sacral Vertebrae
  5. 3 to 5 Coccygeal Vertebrae
  •  The 24 segments of the upper three regions remain distinct throughout life and are termed true or movable vertebrae.
  • The segments in the two lower regions are called false or fixed vertebrae, because of the change they undergo in adults.
  • The sacral segments usually fuse into one bone termed sacrum.
  • Coccygeal segments, referred to as coccyx, often fuse into one bone.

v   Vertebral column presents four curves that arch anteriorly and posteriorly from the midaxillary line of the body.


  1. Cervical
  2. Thoracic
  3. Lumbar
  4. Pelvic
  •  Cervical and Lumbar Curves, which are convex anteriorly and are called Lordotic Curves.
  •  Thoracic and Pelvic Curves are concave anteriorly and are called Kyphotic curves.
  •  The Thoracic and Cervical curves merge smoothly while Lumbar and pelvic curves join at an obtuse angle termed the Lumbosacral or sacrovertebral angle.
  •  The thoracic and pelvic curves are called primary curves, because they are present at birth.
  • Cervical and lumbar curves are called secondary or compensatory curves, because they develop after birth.
  • Cervical curves, which is the least pronounced of the curves, develops when the child begins to hold the head up at about 3 or 4 months of age and begin to sit alone at about 8 to 9 months of age.
  •  The lumbar curves develop when the child begins to walk at about 1 ½ years of age.
  • The lumbar and pelvic curves are more pronounced in females, causing a more acute angle at the lumbosacral junction.


The author is a Radiologic Technologist, currently in the academic field, hoping to mold and produce future Radiologic Technologists who will be theoretically and technologically competent.

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