THE TRUNK and SPINAL COLUMN

1. THE TRUNK and SPINAL COLUMN Chapter 12

2. Bones of the Spinal Column 33 bones, 24 are flexible A. Cervical - 7 B. Thoracic - 12 C. Lumbar - 5 D. Sacrum - 5 (false vertebrae - fused together) E. Coccyx - 4 (false vertebrae - fused together) • LINK Click on picture

3. Landmarks of the Vertebrae

4. General Landmarks 1. Spinous process 3. Transverse process - tubercle of rib articulates 5. Body 6. Vertebral foramen

5. General Landmarks • Vertebral notch • Superior • Inferior

6. General Landmarks • Intervertebral foramen

7. Cervical Vertebrae

8. Cervical Vertebrae • First 7 vertebrae • Identified as C1 – C7 • C1 = Atlas • C2 = Axis

9. Atlas (C1) • Large vertebral foramen • Transverse ligament Anterior Posterior

10. Axial (C2) • Odontoid process or Dens

11. Thoracic (T1-T12)

12. Thoracic (T1-T12)

13. Lumbar (L1-L5)

14. Lumbar (L1-L5)

15. Note the differences: • Transverse process • Spinous process • Body

16. Note the differences: • Transverse process • Spinous process • Body

17. Sacrum

18. Intervertebral Disks

19. Intervertebral Disks

20. Actions of the Spinal Column • Flexion • Extension • Lateral Flexion • Rotation • Same side • Opposite side

21. Flexion Cervical flexion 1. Free in all three regions 2. Cervical and thoracic curves may be reduced to straight lines 3. Lumbar curve may be reversed in flexible subjects Lumbar flexion

22. Extension Cervical extension 1. Free in all three regions 2. Cervical and thorasic curves may be reduced to straight lines 3. Lumbar curve may be reversed in flexible subjects Lumbar extension

23. Lateral flexion Cervical lateral flexion 1. Free in cervical and lumbar regions 2. Limited in thorasic region by rib attachments 3. Accompanied by torsion Lumbar lateral flexion

24. Rotation Cervical rotation 1. Freest at top, least free at bottom 2. Accompanied by slight lateral flexion Lumbar rotation

25. Joints of the Spinal Column

26. Atlantooccipital joint • Articulation between the head and neck • i. Atlas (C1) • ii. Occipital bone • Acts as a hinge joint;flexion and extension • No rotation at this joint

27. Atlantoaxial • Articulation between C1 and C2 • a. pivot joint - rotation is here • b. the dens or ondontoid process fits into the inner, anterior portion of the vertebral foramen • with the help of the transverse ligament.

28. Arthordial or gliding-type joints • Composed of the synovial joint between superior and inferior articulating surfaces

29. Cartilaginous or synarthrodial joints • Intervertebral disks • i. nucleus pulposus - gel • ii. annulus fibrosus - covering • Shape and thickness varies with location • Make up approximately 25% of the column length • Allow limited motion in all three planes

30. Defects of the Spine

32. Kyphosis - hunchback • Increase anterior concavity ( or curvature) of the thoracic curve

34. Lordosis - swayback • Increase posterior concavity of the lumbar region. • it causes shortened back extensors • it causes lengthened abdominal

36. Scoliois • Lateral curvatures or sideward deviations of the spine. • Decreases the ability of the spin to support the body • Distorts the body cavity and that crowds the organs • Puts pressure on the nerves • Causes: • Imbalance of the deep back muscles and ligaments

37. Scoliois • Treatment • Body cast • Electrical stimulation of deep muscles • Harrington Rod implant - ratchett effect

39. Sternum

40. Ribs • 12 pairs • 7 pair are ‘true’ ribs • 5 pair are ‘false’ ribs • 3 pair attach indirectly to the sternum • 2 pair are ‘floating ribs’ that don’t attach to the sternum

41. Ribs