The vertebral column
consists of 24 vertebrae,
the sacrum, and the coccyx.
Joints of the vertebral bodies
Intervertebral discs
between bodies of adjacent vertebrae, composed of:
Nucleus pulposus:
an inner soft, pulpy, highly elastic structure (gelatinous core )
Annulus fibrosus:
an outer fibrous ring consisting of fibrocartilage
Anterior longitudinal ligament
Strong band covering the anterior part of the vertebral bodies and intervertebral discs running from the anterior margin of foramen magnum to the S1~S2.
Maintains stability of the intervertebral disc and prevents hyperextension of the vertebral column.
Posterior longitudinal ligament
Attached to the posterior aspect of the intervertebral discs and posterior edges of the vertebral bodies from C2 vertebra to sacrum
Prevents hyperflexion of the vertebral column and posterior protrusion of the discs
Joints of the vertebral arches
Ligamenta flava ― elastic ligament, unite laminae of adjacent vertebrae, and complete the posterior wall of vertebral canal; tend to prevent hyperflexion of the vertebral column
Interspinal ligament
Supraspinal ligament
Ligamentum nuchae
Intertansverse ligament
Zygapophysial joint
Atlantooccipital joint
Between superior articulating surfaces of atlas and occipital condyles
Supported by membrances and ligaments that join occipital bone and atlas
Action ― nodding of head, lateral tilting of head
Normal Curves of vertebral column
Thoracic cage
Composition
Bones ― consists of twelve thoracic vertebrae, twelve pairs of ribs and costal cartilages, and sternum
General features of thoracic cage
Roughly cone-shape, narrow above and broad below, flattened from before-backwards, longer behind than in front.
Inlet of thorax: bounded by upper border of manubrium, first rib, and vertebra T1
Outlet of thorax: bounded by vertebra T12, 12th and 11th ribs, costal arch and xiphoid process
Infrasternal angle: formed by the costal arch of both side
Intercostal spaces: lie between the ribs
Functions:
protects the organs in the thoracic cavity and upper abdominal cavity;
plays a vital role in the process of breathing.
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