Download - Copyright © 2010 Pearson Education, Inc. The Vertebral Column Yes, this is a Predator Ewok…
Copyright © 2010 Pearson Education, Inc.
The Vertebral Column
Yes, this is a Predator Ewok….
Copyright © 2010 Pearson Education, Inc.
The Vertebral Column
• Supports weight of trunk and distributes weight to lower limbs
• Surrounds and protects spinal cord
• Flexible curved structure composed of 26 irregular bones (vertebrae)
• Cervical vertebrae (7)—vertebrae of the neck
• Thoracic vertebrae (12)—vertebrae of the thoracic cage
• Lumbar vertebrae (5)—vertebra of the lower back
• Sacrum—bone inferior to the lumbar vertebrae
• Coccyx—end of vertebral column
General Characteristics
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Vertebral Column: Curvatures
• Increase the resilience and flexibility of the spine
• Two concave curvatures
• Cervical and lumbar
• Two convex curvatures
• Thoracic and sacral
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Kyphosis LordosisScoliosis
Abnormal Spine Curvatures
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Ligaments
• Anterior and posterior longitudinal ligaments
• From neck to sacrum
• Ligamentum flavum
• Connects adjacent vertebrae
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Intervertebral Discs
• Cushionlike pad between vertebrae; acts like a shock absorber
• Composed of two parts
1. Nucleus pulposus
• Inner gelatinous nucleus that gives the disc its elasticity and compressibility
2. Anulus fibrosus
• Outer collar composed of collagen and fibrocartilage
• Limits the expansion of the nucleus pulposus when the spine is compressed
• Withstands twisting forces on the spine and resists tension on spine
Copyright © 2010 Pearson Education, Inc. Figure 7.17a
Supraspinous ligamentIntervertebraldisc
Anteriorlongitudinalligament
Intervertebral foramen
Posterior longitudinalligament
Anulus fibrosus
Nucleus pulposus
Sectioned bodyof vertebra
Transverse process
Sectionedspinous process
Ligamentum flavum
Interspinousligament
Inferior articular process
Median section of three vertebrae, illustrating the composition of the discs and the ligaments
Copyright © 2010 Pearson Education, Inc. Figure 7.17c
Vertebral spinous process(posterior aspect of vertebra)
Spinal nerve root
Anulus fibrosusof disc
Herniated portionof disc
Nucleuspulposusof disc
Spinal cord
(c) Superior view of a herniated intervertebral disc
Transverseprocess
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General Structure of Vertebrae
• Body or centrum
• Anterior weight-bearing region
• Vertebral arch
• Composed of pedicles and laminae that, along with the body, enclose vertebral foramen
• Vertebral foramina
• Together make up vertebral canal for spinal cord
• Intervertebral foramina
• Lateral openings between adjacent vertebrae for spinal nerves
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General Structure of Vertebrae
• Seven processes per vertebra:
• Spinous process—projects posteriorly
• Transverse processes (2)—project laterally
• Superior articular processes (2)—protrude superiorly inferiorly
• Inferior articular processes (2)—protrude inferiorly
Copyright © 2010 Pearson Education, Inc. Figure 7.18
Posterior
Anterior
Lamina
Superiorarticularprocessandfacet
Transverseprocess
Pedicle
Spinousprocess
Vertebralarch
VertebralforamenBody(centrum)
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CHECK POINT!!!
What are the 5 major regions of the vertebral column?
How many curvatures of the spine are there? And what are they?
Which structure of the spine acts as a shock absorber?
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Bell Ringer!!!!(All Bell Ringers Due Friday)
• What ligaments (that we talked about) support and reinforce the spinal column and describe their location?
• How many spinal processes does each typical vertebra have?
• List and describe the 2 major components of the intervertebral discs
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Cervical Vertebrae
• C1 to C7: smallest, lightest vertebrae
• C1 (atlas) and C2 (axis) have unique features
• C3 to C7 share the following features
• Oval body
• Spinous processes are bifid (except C7)
• Large, triangular vertebral foramen
• Transverse foramen in each transverse process
Copyright © 2010 Pearson Education, Inc. Table 7.2
Copyright © 2010 Pearson Education, Inc.
Cervical Vertebrae
Atlas (C1)
• No body or spinous process
• No intervertebral disk between C1 and C2
• Consists of anterior and posterior arches, and two lateral masses
• Superior surfaces of lateral masses articulate with the occipital condyles
• Allow you to nod your head “yes”
Copyright © 2010 Pearson Education, Inc. Figure 7.19a-b
Anterior arch
Superiorarticularfacet
Transverseforamen
Posterior arch
Posteriortubercle
Anteriortubercle
Posterior
Lateralmasses
(a) Superior view of atlas (C1)
C1
Facet for dens
Transverseprocess
Lateralmasses
Transverseforamen
Posterior archPosteriortubercle
Posterior
Anterior tubercle
Anteriorarch
(b) Inferior view of atlas (C1)
Inferiorarticularfacet
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• Dens projects superiorly into the anterior arch of the atlas
• Dens is a pivot for the rotation of the atlas
• Allows you to rotate head from side to side to say “no”
Axis (C2)
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C2
Posterior
Dens
(c) Superior view of axis (C2)
Inferiorarticularprocess
Body
Superiorarticularfacet
Transverseprocess
Pedicle
Lamina
Spinous process
Figure 7.19c
Copyright © 2010 Pearson Education, Inc. Figure 7.20a
Dens of axis
Transverse ligamentof atlasC1 (atlas)
C2 (axis)
Bifid spinousprocess
Transverse processes
C7 (vertebraprominens)
(a) Cervical vertebrae
C3
Inferior articularprocess
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Thoracic Vertebrae
• T1 to T12
• All articulate with ribs at facets and demifacets
• Heart-shaped body
• The vertebral foramen is circular
• Long spinous process
• Location of articular facets allows rotation of this area of spine
Copyright © 2010 Pearson Education, Inc. Table 7.2
Copyright © 2010 Pearson Education, Inc. Figure 7.20b
Transverseprocess
Spinousprocess
Superior articularprocess
Transversecostal facet (fortubercle of rib)
Body
Intervertebraldisc
Inferior costalfacet (for headof rib)Inferior articularprocess
(b) Thoracic vertebrae
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Lumbar Vertebrae
• L1 to L5
• Short, thick pedicles and laminae
• Flat hatchet-shaped spinous processes
• Vertebral foramen is triangular
• Orientation of articular facets locks lumbar vertebrae together so as to prevent rotation
Copyright © 2010 Pearson Education, Inc. Table 7.2
Copyright © 2010 Pearson Education, Inc. Figure 7.20c
Superiorarticularprocess
Transverseprocess
Spinousprocess
Intervertebraldisc
Body
Inferiorarticularprocess
(c) Lumbar vertebrae
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Sacrum and Coccyx
• Sacrum
• 5 fused vertebrae (S1–S5)
• Forms posterior wall of pelvis
• Articulates with L5 superiorly, and with auricular surfaces of the hip bones laterally
• Coccyx
• Tailbone
• 3–5 fused vertebrae
• Articulates superiorly with sacrum
Copyright © 2010 Pearson Education, Inc. Figure 7.21a
Coccyx
Anteriorsacralforamina
Apex
Sacral promontory
AlaBody offirstsacralvertebra
Transverseridges (sites of vertebral fusion)
(a) Anterior view
Copyright © 2010 Pearson Education, Inc. Figure 7.21b
Coccyx
Posteriorsacralforamina
Mediansacralcrest
Sacralcanal
Sacralhiatus
Body Facet ofsuperiorarticular process
Lateralsacralcrest
Auricularsurface
Ala
(b) Posterior view
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CHECK POINT!!!
What are the 1st two cervical vertebra called and what makes them different?
How can you tell the difference between a lumbar vertebrae and a thoracic vertebrae?
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Bell Ringer!!!!(All Bell Ringers Due Friday)
• What distinguishing features do cervical vertebrae have that thoracic and lumbar vertebrae do not?
• Why to lumbar vertebrae have the larges bodies?
• How many cervical, thoracic and lumbar vertebrae do we have?
• How many vertebrae make up the sacrum and the coccyx?
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Thoracic Cage
• Composed of
• Thoracic vertebrae
• Sternum
• Ribs and their costal cartilages
• Functions
• Protects vital organs of thoracic cavity
• Supports shoulder girdle and upper limbs
• Provides attachment sites for many muscles, including intercostal muscles used during breathing
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Sternum (Breastbone)
• Three fused bones
• Manubrium
• Articulates with clavicles and ribs 1 and 2
• Body
• Articulates with costal cartilages of ribs 2 through 7
• Xiphoid process
• Site of muscle attachment
• Not ossified until ~ age 40
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Ribs and Their Attachments
• 12 pairs
• All attach posteriorly to thoracic vertebrae
• Pairs 1 through 7
• True (vertebrosternal) ribs
• Attach directly to the sternum by individual costal cartilages
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Ribs and Their Attachments
• Pairs 8 through12
• False ribs
• Pairs 8–10 also called vertebrochondral ribs
• Attach indirectly to sternum by joining costal cartilage of rib above
• Pairs 11–12 also called vertebral (floating) ribs
• No attachment to sternum
Copyright © 2010 Pearson Education, Inc. Figure 7.22a
Intercostal spaces
Trueribs(1–7)
Falseribs(8–12)
Jugular notchClavicular notch
ManubriumSternal angleBodyXiphisternaljointXiphoidprocess
L1
Vertebra Floating ribs (11, 12)(a) Skeleton of the thoracic cage, anterior view
Sternum
Costal cartilage
Costal margin
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Structure of a Typical Rib
• Main parts:
• Head
• Articulates posteriorly with facets (demifacets) on bodies of two adjacent vertebrae
• Neck
• Tubercle
• Articulates posteriorly with transverse costal facet of same-numbered thoracic vertebra
• Shaft
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Copyright © 2010 Pearson Education, Inc. Figure 7.23b
Spinous processArticular faceton tubercle of rib
Shaft
Ligaments
Neck of rib
Head of rib Body ofthoracicvertebra
Transversecostal facet(for tubercleof rib)
Superior costal facet(for head of rib)
(b) Superior view of the articulation between arib and a thoracic vertebra
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CHECK POINT!!!
How does a true rib differ from a false rib?
Besides the ribs and sternum, there is a 3rd group of bones that makes up the thoracic cage. What is it?
What are floating ribs?