7Vertebral ColumnVertebral Column: CurvaturesSlide 4LigamentsIntervertebral DiscsSlide 7Slide 8General Structure of VertebraeSlide 10Slide 11Cervical VertebraeSlide 13Slide 14Slide 15Slide 16Slide 17Slide 18Thoracic VertebraeSlide 20Slide 21Lumbar VertebraeSlide 23Slide 24Sacrum and CoccyxSlide 26Slide 27Thoracic CageSternum (Breastbone)Ribs and Their AttachmentsSlide 31Slide 32Structure of a Typical RibSlide 34Slide 35PowerPoint® Lecture Slides prepared by Janice Meeking, Mount Royal CollegeC H A P T E RCopyright © 2010 Pearson Education, Inc.7 The Skeleton: Part BCopyright © 2010 Pearson Education, Inc.Vertebral Column•Transmits weight of trunk to lower limbs•Surrounds and protects spinal cord•Flexible curved structure containing 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—terminus of vertebral columnCopyright © 2010 Pearson Education, Inc.Vertebral Column: Curvatures•Increase the resilience and flexibility of the spine•Two posteriorly concave curvatures•Cervical and lumbar•Two posteriorly convex curvatures•Thoracic and sacral•Abnormal spine curvatures•Scoliosis (abnormal lateral curve)•Kyphosis (hunchback)•Lordosis (swayback)Copyright © 2010 Pearson Education, Inc.Figure 7.16Cervical curvature (concave)7 vertebrae, C1–C7Thoracic curvature(convex)12 vertebrae,T1–T12Lumbar curvature(concave)5 vertebrae, L1–L5Sacral curvature(convex)5 fused vertebrae sacrumCoccyx4 fused vertebraeAnterior view Right lateral viewSpinousprocessTransverseprocessesIntervertebraldiscsIntervertebralforamenC1Copyright © 2010 Pearson Education, Inc.Ligaments•Anterior and posterior longitudinal ligaments•From neck to sacrum•Ligamentum flavum•Connects adjacent vertebrae•Short ligaments•Connect each vertebra to those above and belowCopyright © 2010 Pearson Education, Inc.Intervertebral Discs•Cushionlike pad composed of two parts1. Nucleus pulposus•Inner gelatinous nucleus that gives the disc its elasticity and compressibility2. Anulus fibrosus•Outer collar composed of collagen and fibrocartilageCopyright © 2010 Pearson Education, Inc.Figure 7.17aSupraspinous ligamentIntervertebraldiscAnteriorlongitudinalligamentIntervertebral foramenPosterior longitudinalligamentAnulus fibrosusNucleus pulposusSectioned bodyof vertebraTransverse processSectionedspinous processLigamentum flavumInterspinousligamentInferior articular process Median section of three vertebrae, illustrating the composition of the discs and the ligamentsCopyright © 2010 Pearson Education, Inc.Figure 7.17cVertebral spinous process(posterior aspect of vertebra)Spinal nerve rootAnulus fibrosusof discHerniated portionof discNucleuspulposusof discSpinal cord(c) Superior view of a herniated intervertebral discTransverseprocessCopyright © 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 centrum, enclose vertebral foramen•Vertebral foramina•Together make up vertebral canal for spinal cord •Intervertebral foramina•Lateral openings between adjacent vertebrae for spinal nervesCopyright © 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 inferiorlyPLAYPLAYAnimation: Rotatable Spine (horizontal)PLAYPLAYAnimation: Rotatable Spine (vertical)Copyright © 2010 Pearson Education, Inc.Figure 7.18PosteriorAnteriorLaminaSuperiorarticularprocessandfacetTransverseprocessPedicleSpinousprocessVertebralarchVertebralforamenBody(centrum)Copyright © 2010 Pearson Education, Inc.Cervical Vertebrae•C1 to C7: smallest, lightest vertebrae•C3 to C7 share the following features •Oval body•Spinous processes are bifid (except C7)•Large, triangular vertebral foramen•Transverse foramen in each transverse processCopyright © 2010 Pearson Education, Inc.Table 7.2Copyright © 2010 Pearson Education, Inc.Figure 7.20aDens of axisTransverse ligamentof atlasC1 (atlas)C2 (axis)Bifid spinousprocessTransverse processesC7 (vertebraprominens)(a) Cervical vertebraeC3Inferior articularprocessCopyright © 2010 Pearson Education, Inc.Cervical Vertebrae•C1 (atlas) and C2 (axis) have unique features •Atlas (C1)•No body or spinous process•Consists of anterior and posterior arches, and two lateral masses•Superior surfaces of lateral masses articulate with the occipital condylesCopyright © 2010 Pearson Education, Inc.Figure 7.19a-bAnterior archSuperiorarticularfacetTransverseforamen Posterior archPosteriortubercleAnteriortubercle PosteriorLateralmasses(a) Superior view of atlas (C1)C1Facet for densTransverseprocessLateralmassesTransverseforamen Posterior archPosteriortubercle PosteriorAnterior tubercleAnteriorarch (b) Inferior view of atlas (C1)InferiorarticularfacetCopyright © 2010 Pearson Education, Inc.Cervical Vertebrae•Axis (C2)•Dens projects superiorly into the anterior arch of the atlas•Dens is a pivot for the rotation of the atlasCopyright © 2010 Pearson Education, Inc.C2PosteriorDens(c) Superior view of axis (C2)InferiorarticularprocessBodySuperiorarticularfacetTransverseprocessPedicleLaminaSpinous processFigure 7.19cCopyright © 2010 Pearson Education, Inc.Thoracic Vertebrae•T1 to T12•All articulate with ribs at facets and demifacets•Long spinous process•Location of articular facets allows rotation of this area of spineCopyright © 2010 Pearson Education, Inc.Table 7.2Copyright © 2010 Pearson Education, Inc.Figure 7.20bTransverseprocessSpinousprocessSuperior articularprocessTransversecostal facet (fortubercle of rib)BodyIntervertebraldiscInferior costalfacet (for headof rib)Inferior articularprocess(b) Thoracic vertebraeCopyright © 2010 Pearson Education, Inc.Lumbar Vertebrae•L1 to L5 •Short, thick pedicles and laminae•Flat hatchet-shaped spinous processes •Orientation of articular facets locks lumbar vertebrae together so as to prevent rotationCopyright © 2010 Pearson Education, Inc.Table 7.2Copyright © 2010 Pearson Education, Inc.Figure