1. PowerPoint ® Lecture Slides prepared by Leslie Hendon University of Alabama, Birmingham C H A P T E R Copyright © 2011 Pearson Education, Inc. Part 4 7 Bones, Part 1: The Axial Skeleton

2. Copyright © 2011 Pearson Education, Inc. The Vertebral Column Formed from 26 bones in the adult Transmits weight of trunk to the lower limbs Surrounds and protects the spinal cord

3. Copyright © 2011 Pearson Education, Inc. The Vertebral Column Serves as attachment sites for muscles of the neck and back Held in place by ligaments Anterior and posterior longitudinal ligaments Ligamentum flavum

4. Copyright © 2011 Pearson Education, Inc. The Vertebral Column Figure 7.18 Cervical curvature (concave) 7 vertebrae, C 1 – C 7 Thoracic curvature (convex) 12 vertebrae, T 1 – T 12 Lumbar curvature (concave) 5 vertebrae, L 1 – L 5 Sacral curvature (convex) 5 fused vertebrae sacrum Coccyx 4 fused vertebrae Anterior viewRight lateral view C1C1 T 1 2 3 4 5 6 7 8 9 10 11 12 L 1 2 3 4 5 2 3 4 5 6 7 Spinous process Transverse processes Intervertebral discs Intervertebral foramen

5. Copyright © 2011 Pearson Education, Inc. Regions and Normal Curvatures The Vertebral column has five major regions 7 cervical vertebrae of the neck region 12 thoracic vertebrae 5 lumbar vertebrae Sacrum—five fused bones Inferior to lumbar vertebrae Coccyx—inferior to sacrum

6. Copyright © 2011 Pearson Education, Inc. Regions and Normal Curvatures Curvatures of the spine Cervical and lumbar curvatures Concave posteriorly Thoracic and sacral curvatures Convex posteriority

7. Copyright © 2011 Pearson Education, Inc. Regions and Normal Curvatures Curvatures increase resilience of spine Thoracic and sacral curvatures Primary curvatures Present at birth Lumbar curvature Develops when baby begins to walk

8. Copyright © 2011 Pearson Education, Inc. Ligaments of the Spine Major supporting ligaments Anterior longitudinal ligament Attaches to bony vertebrae and intervertebral discs Prevents hyperextension Posterior longitudinal ligament Narrow and relatively weak Attaches to intervertebral discs

9. Copyright © 2011 Pearson Education, Inc. Posterior longitudinal ligament Anterior longitudinal ligament Body of a vertebra Intervertebral disc (b) Anterior view of part of the spinal column Ligaments of the Spine 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 (a)Median section of three vertebrae, illustrating the composition of the discs and the ligaments Figure 7.19a, b

10. Copyright © 2011 Pearson Education, Inc. Ligaments of the Spine Figure 7.19c, d 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 (d)MRI of lumbar region of vertebral column in sagittal section showing normal and herniated discs Nucleus pulposus of intact disc Herniated nucleus pulposus

11. Copyright © 2011 Pearson Education, Inc. Intervertebral Discs Are cushion-like pads between vertebrae Composed of Nucleus pulposus Anulus fibrosus

12. Copyright © 2011 Pearson Education, Inc. Intervertebral Discs Nucleus pulposus Gelatinous inner sphere Absorbs compressive stresses Anulus fibrosus Outer fings formed of ligament Inner rings formed of fibrocartilage Contain the nucleus pulposus

13. Copyright © 2011 Pearson Education, Inc. General Structure of Vertebrae PLAY Spine (horizontal) Figure 7.20 Posterior Anterior Lamina Superior articular process and facet Transverse process Pedicle Spinous process Vertebral arch Vertebral foramen Body (centrum)

14. Copyright © 2011 Pearson Education, Inc. General Structure of Vertebrae Common structures to all regions Body Vertebral arch Vertebral foramen Spinous process Transverse process Superior and inferior articular processes Intervertebral foramina