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

Copyright © 2010 Pearson Education, Inc. Vertebral Column: Curvatures Increase the resilience and flexibility of the spine Two concave curvatures Cervical and lumbar Two convex curvatures Thoracic and sacral

Copyright © 2010 Pearson Education, Inc. KyphosisLordosisScoliosis Abnormal Spine Curvatures

Copyright © 2010 Pearson Education, Inc. Ligaments Anterior and posterior longitudinal ligaments From neck to sacrum Ligamentum flavum Connects adjacent vertebrae

Copyright © 2010 Pearson Education, Inc. 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 ligament Intervertebral disc Anterior longitudinal ligament Intervertebral foramen Posterior longitudinal ligament Anulus fibrosus Nucleus pulposus Sectioned body of vertebra Transverse process Sectioned spinous process Ligamentum flavum Interspinous ligament 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 fibrosus of disc Herniated portion of disc Nucleus pulposus of disc Spinal cord (c) Superior view of a herniated intervertebral disc Transverse process

Copyright © 2010 Pearson Education, Inc. 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

Copyright © 2010 Pearson Education, Inc. 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 Superior articular process and facet Transverse process Pedicle Spinous process Vertebral arch Vertebral foramen Body (centrum)

Copyright © 2010 Pearson Education, Inc. 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?

Copyright © 2010 Pearson Education, Inc. 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

Copyright © 2010 Pearson Education, Inc. Cervical Vertebrae C 1 to C 7 : smallest, lightest vertebrae C 1 (atlas) and C 2 (axis) have unique features C 3 to C 7 share the following features Oval body Spinous processes are bifid (except C 7 ) 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 (C 1 ) No body or spinous process No intervertebral disk between C 1 and C 2 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 Superior articular facet Transverse foramen Posterior arch Posterior tubercle Anterior tubercle Posterior Lateral masses (a) Superior view of atlas (C 1 ) C1C1 Facet for dens Transverse process Lateral masses Transverse foramen Posterior arch Posterior tubercle Posterior Anterior tubercle Anterior arch (b) Inferior view of atlas (C 1 ) Inferior articular facet

Copyright © 2010 Pearson Education, Inc. 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 (C 2 )

Copyright © 2010 Pearson Education, Inc. C2C2 Posterior Dens (c) Superior view of axis (C 2 ) Inferior articular process Body Superior articular facet Transverse process Pedicle Lamina Spinous process Figure 7.19c

Copyright © 2010 Pearson Education, Inc. Figure 7.20a Dens of axis Transverse ligament of atlas C 1 (atlas) C 2 (axis) Bifid spinous process Transverse processes C 7 (vertebra prominens) (a) Cervical vertebrae C3C3 Inferior articular process

Copyright © 2010 Pearson Education, Inc. Thoracic Vertebrae T 1 to T 12 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 Transverse process Spinous process Superior articular process Transverse costal facet (for tubercle of rib) Body Intervertebral disc Inferior costal facet (for head of rib) Inferior articular process (b) Thoracic vertebrae

Copyright © 2010 Pearson Education, Inc. Lumbar Vertebrae L 1 to L 5 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 Superior articular process Transverse process Spinous process Intervertebral disc Body Inferior articular process (c) Lumbar vertebrae

Copyright © 2010 Pearson Education, Inc. Sacrum and Coccyx Sacrum 5 fused vertebrae (S 1 – S 5 ) Forms posterior wall of pelvis Articulates with L 5 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 Anterior sacral foramina Apex Sacral promontory Ala Body of first sacral vertebra Transverse ridges (sites of vertebral fusion) (a) Anterior view

Copyright © 2010 Pearson Education, Inc. Figure 7.21b Coccyx Posterior sacral foramina Median sacral crest Sacral canal Sacral hiatus Body Facet of superior articular process Lateral sacral crest Auricular surface Ala (b) Posterior view

Copyright © 2010 Pearson Education, Inc. 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?

Copyright © 2010 Pearson Education, Inc. 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?

Copyright © 2010 Pearson Education, Inc. 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

Copyright © 2010 Pearson Education, Inc. 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

Copyright © 2010 Pearson Education, Inc. 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

Copyright © 2010 Pearson Education, Inc. 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 True ribs (1–7) False ribs (8–12) Jugular notch Clavicular notch Manubrium Sternal angle Body Xiphisternal joint Xiphoid process L 1 Vertebra Floating ribs (11, 12) (a) Skeleton of the thoracic cage, anterior view Sternum Costal cartilage Costal margin

Copyright © 2010 Pearson Education, Inc. 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

Copyright © 2010 Pearson Education, Inc.

Figure 7.23b Spinous process Articular facet on tubercle of rib Shaft Ligaments Neck of rib Head of rib Body of thoracic vertebra Transverse costal facet (for tubercle of rib) Superior costal facet (for head of rib) (b) Superior view of the articulation between a rib and a thoracic vertebra

Copyright © 2010 Pearson Education, Inc. CHECK POINT!!! How does a true rib differ from a false rib? Besides the ribs and sternum, there is a 3 rd group of bones that makes up the thoracic cage. What is it? What are floating ribs?