Cervical Vertebrae

• Typical & Atypical Cervical Vertebrae


  the 7 cervical vertebrae, C1-C7, r the smallest, lightest vertebrae

  the typical cervical vertebrae = C3-C7

  C1 = atlas

  C2= axis

  
• Distinguishing Features of Typical Cervical Vertebrae

  C3-C7

  body is oval - wider from side to side than in the antero-posterior dimension

  vertebral foramen is large + triangular

  each transverse process contains a transverse foramen thru which the vertebral arteries pass to service the brain
• Atlas & Axis


  the 1st 2 cervical vertebrae, the atlas + axis, r more rubust than the typical cervical vertebrae

  they have no intervertebral disc between them + they r highly modified, reflecting their special functions
• Atlas


  the atlas (C1) has no body + no spinous process

  it is a ring of bone consisting of anterior + posterior arches + a lateral mass on each side

  each lateral mass has articular facets on both its usperior + inferior surfaces

  the superior articular facets receive the occipital condyles of the skull - they carry the skull

  the inferior facets form joints w the axis (C2) below

  
• Axis


  the axis (C2) which has a body + the other typical vertebral processses is not as specialised as the atlas

  its only unusual feature is the knoblike dens projecting superiorly from its body

  the dens is the missing body of the atlas, which fuses w the axis during embryonic development

  cradled in the anterior arch of the atlas by the transverse ligament, the dens acts as a pivot for the rotation of the atlas

  = rotatete head from side to side