THE BACK VERTEBRAE VERTEBRAL COLUMN TOPICS THE BONES and THE - PowerPoint PPT Presentation

THE BACK VERTEBRAE VERTEBRAL COLUMN

TOPICS • THE BONES and THE JOINTS OF THE BACK • THE TYPICAL VERTEBRA • THE INTERVERTEBRAL DISC • THE CERVICAL VERTEBRAE • THE THORACIC VERTEBRAE • THE LUMBAR VERTEBRAE • THE SACRUM • THE COCCYX • THE JOINTS OF VERTEBRAL COLUMN • THE LIGAMENTS OF VERTEBRAL COLUMN • THE CURVATURES OF VERTEBRAL COLUMN • THE VASCULATURE OF VERTEBRAL COLUMN • THE LEVEL CORRESPONDING STRUCTURE

THE VERTEBRAE

THE BONES and THE JOINTS OF THE BACK

THE BACK THE BACK - BONES & JOINTS The back comprises the posterior aspect of the trunk, inferior to the neck and superior to the buMocks. The vertebral column extends from the cranium (skull) to the apex of the coccyx.

THE VERTEBRAE THE BACK - BONES & JOINTS The vertebral column in an adult consists of 33 vertebrae arranged in five regions: • 7 cervical C1-C7 • 12 thoracic T1-T12 • 5 lumbar L1-L5 • 5 sacral S1-S5 • 4 coccygeal

THE VERTEBRAE THE BACK - BONES & JOINTS Significant mo]on occurs only between the 25 superior vertebrae . Of the 9 inferior vertebrae, the 5 sacral vertebrae are fused in adults to form the sacrum , and a`er approximately age 30, the 4 coccygeal vertebrae fuse to form the coccyx .

THE VERTEBRAE THE BACK - BONES & JOINTS THE TYPICAL VERTEBRA

THE VERTEBRAE THE BACK - BONES & JOINTS A typical vertebra consists of a: • vertebral body • vertebral arch • seven processes The vertebral body is the more massive, cylindrical, anterior part of the bone that gives strength to the vertebral column and supports body weight. The vertebral arch is posterior to the vertebral body and consists of 2 (right and le`) pedicles and 2 laminae. The vertebral arch and the posterior surface of the vertebral body form the walls of the vertebral foramen.

THE VERTEBRAE THE BACK - BONES & JOINTS The vertebral arch encloses the vertebral (foramen) canal that houses the spinal cord . The canal contains the spinal cord and the roots of the spinal nerves , along with the membranes ( meninges ), fat , and vessels that surround and serve them.

THE VERTEBRAE THE BACK - BONES & JOINTS Vertebral notches of adjacent pedicles form intervertebral foramina that provide for the exit of the spinal nerves . The dorsal projec]ng spines and the lateral projec]ng transverse processes provide aRachment sites for muscles and ligaments .

THE VERTEBRAE THE BACK - BONES & JOINTS Seven processes arise from the vertebral arch of a typical vertebra: • One median spinous process projects posteriorly from the vertebral arch at the junc]on of the laminae. • Two transverse processes project posterolaterally from the junc]ons of the pedicles and laminae. • Four arScular processes : two superior and two inferior also arise from the junc]ons of the pedicles and laminae, each bearing an ar]cular surface (facet).

THE VERTEBRAE THE BACK - BONES & JOINTS The ar]cular processes are in apposi]on with corresponding processes of vertebrae adjacent (superior and inferior) to them, forming zygapophysial (facet) joints The intervertebral disks contribute to about 25% of the length of the vertebral column. They form the car]laginous joints between the vertebral bodies and provide limited movements between the individual vertebrae.

THE BACK - BONES & JOINTS THE INTERVERTEBRAL DISK

THE VERTEBRAE THE BACK - BONES & JOINTS Each intervertebral disk is numbered by the vertebral body above the disk.

THE VERTEBRAE THE BACK - BONES & JOINTS Each intervertebral disk is composed of the following: • Anulus fibrosus consists of the outer concentric rings of fibrocar]lage and fibrous connec]ve ]ssue. • Nucleus pulposus is an inner so`, elas]c, The hernia]on of a compressible material that nucleus pulposus is most func]ons as a shock commonly in a absorber posterolateral direcSon due to the strength and posi]on of the posterior longitudinal ligament

THE BACK - BONES & JOINTS CERVICAL VERTEBRAE

THE NECK THE NECK - BONES & JOINTS 7 cervical vertebrae form the cervical region of the vertebral column, which encloses the spinal cord and meninges. CERVICAL VERTEBRAE - CHARACTERISTICS - the smallest of the 24 movable vertebrae - the most dis]nc]ve feature of each cervical vertebra is the oval foramen transversarium (transverse foramen) in the transverse process

THE NECK - BONES & JOINTS THE CERVICAL VERTEBRAE The most dis]nc]ve feature of each cervical vertebra is the oval foramen transversarium (transverse foramen) in the transverse process.

THE NECK THE NECK - BONES & JOINTS THE CERVICAL VERTEBRAE The four typical cervical vertebrae C3–C6 have the following characteris]cs: • The vertebral body is small and longer from side to side than anteroposteriorly; the superior surface is concave, and the inferior surface is convex. • The vertebral foramen is large and triangular . • The transverse processes of all cervical vertebrae (typical or atypical) include foramina transversaria for the vertebral vessels (the vertebral veins and, except for vertebra C7, the vertebral arteries). • Their spinous processes are short and bifid . • The transverse processes of cervical vertebrae end laterally in two projec]ons: an anterior tubercle and a posterior tubercle . The anterior rami of the cervical spinal nerves course ini]ally on the transverse processes in grooves for spinal nerves between the tubercles.

THE NECK - BONES & JOINTS THE CERVICAL VERTEBRAE The first ( atlas ), second ( axis ) and seventh ( vertebra prominens ) cervical vertebrae are ATYPICAL . Vertebrae C3–C6 are the typical cervical vertebrae.

THE NECK - BONES & JOINTS THE CERVICAL VERTEBRAE There are three atypical cervical vertebrae (C1, C2, and C7): • The C1 vertebra or atlas : a ring-like, kidney-shaped bone lacking a spinous process or body and consis]ng of two lateral masses connected by anterior and posterior arches. Its concave superior ar]cular facets receive the occipital condyles. • The C2 vertebra or axis : a peg-like dens (odontoid process) projects superiorly from its body. The dens is embryologically the vertebral body of the atlas (C1).

THE NECK - BONES & JOINTS THE CERVICAL VERTEBRAE The axis has two large, flat bearing surfaces , the superior ar]cular facets, on which the atlas rotates. The dens lies anterior to the spinal cord and serves as the pivot about which the rota]on of the head occurs. The dens is held in posi]on against the posterior aspect of the anterior arch of the atlas by the transverse ligament of the atlas .

THE NECK - BONES & JOINTS THE CERVICAL VERTEBRAE There are three atypical cervical vertebrae (C1, C2, and C7): • The vertebra prominens (C7 ): so-named because of its long spinous process, which is not bifid. Its transverse processes are large, but its foramina transversaria are small.

THE NECK - BONES & JOINTS THE CERVICAL VERTEBRAE There are three atypical cervical vertebrae (C1, C2, and C7): • The C1 vertebra or atlas : a ring-like, kidney-shaped bone lacking a spinous process or body and consis]ng of two lateral masses connected by anterior and posterior arches. Its concave superior ar]cular facets receive the occipital condyles. • The C2 vertebra or axis : a peg-like dens (odontoid process) projects superiorly from its body. • The vertebra prominens (C7): so-named because of its long spinous process, which is not bifid. Its transverse processes are large, but its foramina transversaria are small.

THE BACK - BONES & JOINTS CERVICAL VERTEBRAE - CHARACTERISTICS C7 is a prominent vertebra that is characterized by a long spinous process - vertebra prominens

THE BACK - BONES & JOINTS CERVICAL VERTEBRAE - CHARACTERISTICS • Vertebra C1, also called the atlas , is unique in that it has neither a body nor a spinous process • C1 ringshaped bone has paired lateral masses • Anterior and posterior arches of C1 , each of which bears a tubercle in the center of its external aspect

THE BACK - BONES & JOINTS CERVICAL VERTEBRAE - CHARACTERISTICS • vertebra C2, also called the axis , is the strongest of the cervical vertebrae • the dis]nguishing feature of C2 is the blunt tooth-like dens (odontoid process) , which projects superiorly from its body • the axis has two large, flat bearing surfaces, the superior arScular facets , on which the atlas rotates

THE BACK - BONES & JOINTS THORACIC VERTEBRAE

THE BACK - BONES & JOINTS THORACIC VERTEBRAE - CHARACTERISTICS The thoracic vertebrae provide aMachment for the ribs the primary characteris]c features of thoracic vertebrae are the costal facets for ar]cula]on with ribs The primary characteris]c features of thoracic vertebrae are the costal facets for arSculaSon with ribs .

THE BACK - BONES & JOINTS LUMBAR VERTEBRAE

THE BACK - BONES & JOINTS LUMBAR VERTEBRAE - CHARACTERISTICS The lumbar vertebrae have massive bodies , accoun]ng for much of the thickness of the lower trunk in the median plane Are dis]nguished by their large bodies, sturdy laminae, and absence of costal facets. The fi`h lumbar vertebra has the largest body of the vertebrae. Are characterized by a strong, massive transverse process and have mamillary and accessory processes .

THE BACK - BONES & JOINTS SACRUM