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Skeletal Anatomy: Vertebrae and Thoracic Cage


(Histology and General Bone Structure)

I). Division & Curvatures

A). Divisions

1). cervical

2). thoracic

3). lumbar

4). sacrum

5). coccyx


vertebral column
B). Curvatures: Increase flexibility and give resiliency and stability

1). cervical curvature

2). thoracic curvature

3). lumbar curvature

4). sacral curvature

(remember meal-times 7-12-5)

breakfast at  7---there are 7 cervical vertebrae

lunch at 12---there are 12 thoracic vertebrae

dinner at 5--there are 5 lumbar vertebrae

C). Abnormal Curvatures

1). scoliosis


2). kyphosis


3). lordosis


abnormal spinal curves

II). Ligaments

A). anterior longitudinal ligaments

B). posterior longitudinal ligaments


vertebral ligaments

III). Intervertebral Foramina

Openings between the vertebrae that allow for the passage of spinal nerves


intervertebral foramen (foramina)




IV). Intervertebral Discs

Act as shock absorbers between the vertebrae.


The discs are for flexing and extending.



vertebral disc with rupture



V). Vertebrae

A). vertebral body

B). vertebral arch is formed from:

1). pedicles extend from the body

2). laminae extend from pedicles & fuse in the midline.

C). vertebral foramen large opening

 forms the vertebral canal.

D). Processes

1). spinous processes

2). transverse processes 

3). superior process

4). inferior processes




VI). Regional Vertebral Differences

A). cervical vertebrae (C1 to C7)

      1).  General Characteristics (C3-C7)

a).  Transverse foramen (opening) along side the transverse processes.

b).  Short bifurcated spinous process

C7 is the first vertebrae seen through the skin


cervical vertebrae


Identify cervical vertebrae by transverse foramen

      2)  C1called the atlas

a).  No body or spinous processes

b).  Large lateral inferior and superior articulating facets (articulates to the occipital condyles)

      3).  C2 called the axis.

a).  Has a body and spine.

b).   Dens or Odontoid Process


The atlas turns on the axis



atlas and axis  C1 and C2

B). thoracic vertebrae (T1 to T12)

1). All thoracic vertebrae articulate with a pair of  ribs with an articular facet.

2). Long spinous process that curves inferiorly.



thoracic vertebraethoracic vertebrae



Identify thoracic vertebrae by the long sharp spinous process


lumbar vertebraelumbar vertebrae


C). lumbar vertebrae (L1 to L5)

1). Large body

2). Short flat spinous processes



Identify lumbar vertebrae by the flat blunt spinous process and thick body

VII). Sacrum (S1 to S5)




A). anterior

1). sacral promontory

2). ventral sacral foramina


B). posterior

1). median sacral crest

2). dorsal sacral 

3). sacral canal

4). sacral hiatus


VIII). Coccyx coccyx
IX.  Thorax Cage





12 ribs attached with costal cartilage


thoracic cage

A).  Sternum

1). Manubrium


2).  Body


3).  Xiphoid Process





B).  Rib Cage

12 pairs of ribs form the rib cage

(male & female)

1).  True Ribs: (1-7)

Superior 7 pairs of ribs attach to the sternum with costal cartilage.

2).   False Ribs (8-10)

3 pairs of ribs lack the sternal attachment, but connect to the costal cartilage of the rib 7.

3). Floating Ribs  (11-12)

no anterior attachment

thoracic cage

structure of the rib

Rib attachment

C). Rib Structure

        1). bow shape

        2). shaft

        3). costal groove

        4). head of the rib

        5). tubercle

X.  Histology

Structure of osteon:

1).  Lamella: each concentric ring of the osteon.

2).  Haversianís canal or osteonic canal:  The canals contain small blood vessels and nerve fibers

3).  Lacuna:  Small chambers between the lamella that contain osteocytes (mature bone cells)



Draw a dry bone slide and label the following structures






Haversian's canal (osteonic canal)



XI. Types of bone

Compact Bone

  Appears dense and solid it consists of structural units called osteons.

Spongy or Trabecular Bone

  Spongy bone consists of a honeycomb or network of flat pieces

Bone is covered in a dense Periosteum


medullary cavity contains:


Red Bone Marrow


Yellow Bone Marrow


long bone structure



All bones are listed in red.

All features and formations that the student is required to know for the practical are listed in blue

Methods to distinguish the specific vertebrae are listed in purple.


walking skeleton from http://fxjoiner.com/movies_from_still_images.htm




skeleton from http://www.rpg-project.com/pages/povani.htm