chapter 5c: the skeletal system
DESCRIPTION
Chapter 5c: The Skeletal System. The Vertebral Column. Vertebrae separated by intervertebral discs Runs from skull to pelvis Transmits weight of body to lower limbs Each vertebrae is given a name according to its location Protects spinal cord. Figure 5.14. The Vertebral Column. - PowerPoint PPT PresentationTRANSCRIPT
Chapter 5c:The Skeletal System
2006
The Vertebral ColumnVertebrae separated by intervertebral discsRuns from skull to pelvisTransmits weight of body to lower limbsEach vertebrae is given a name according to its
locationProtects spinal cord
Figure 5.14
The Vertebral ColumnThere are 24 single vertebral bones separated by
intervertebral discsSeven cervical vertebrae are in the neckTwelve thoracic vertebrae are in the chest regionFive lumbar vertebrae are associated with the
lower backNine vertebrae fuse to form two composite bones:
Sacrumcoccyx
Note how the spine curves in within the thoracic region….Also note that numbering restarts within each section!!
Structure of a Typical Vertebrae, Superior View
2006 HobanFigure 5.16
Vertebral ColumnIntervertebral Discs
Made of Fibrocartilage Cushions each bone & flexibility 90% water (decreases with age) Loss of fluid in discs due to age can lead to “shrinking” in height
Regional Characteristics7 cervical vertebrae
1 = atlas C12 = axis C2C3-C7
Smallest & lightest bones of the vertebrae Include Foramina – vertebral arteries to brain
2006 Hoban
Thoracic – T1 – T12
Lumbar – L1 – L5Massive block-like bodiesSturdiest vertebrae
Sacrum – 5 fused vertebraeForm the posterior wall of pelvis
Coccyx – 3-5 fused vertebraeaka Tailbone – remnant of a tail that other
vertebrates have
2006 Hoban
Regional Characteristics of Vertebrae—Cervical V.
Regional Characteristics of Vertebrae—Thoracic V.
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Regional Characteristics of Vertebrae—Lumbar V.
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Regional Characteristics of Vertebrae—Sacrum & Coccyx
The Vertebral ColumnThe spine has a normal curvature:
Primary curvatures are the spinal curvatures of the thoracic and sacral regionsPresent from birth
Secondary curvatures are the spinal curvatures of the cervical and lumbar regionsDevelop after birth
The Vertebral Column
Abnormal Curvatures
The Bony ThoraxForms a cage to protect major organsConsists of three parts
SternumRibs
True ribs (pairs 1-7)False ribs (pairs 8-12)Floating ribs (pairs 11-12)
Thoracic vertebrae
Figure 5.19a
The Bony Thorax
Figure 5.19a
Sternum – attached to first 7 pair of ribsSternal puncture – for bone marrow biopsy12 pair of ribs
7 true – attach to sternum5 false – attach indirectly or not at all
2 floating
2006 Hoban