A10 Vertebrae 2

Question 1

Recall the different forms of intervertebral joint

Answer 1

Synovial joint, arch → arch (articular facets)

Cartilaginous joint, body → body (intervertebral discs)

Question 2

Describe the particular facet joints/synovial intervertebral articulations

Answer 2

Radially-orientated facets will facilitate dorsal-ventral flexion & extension

Tangentially-orientated facets facilitate lateroflexion & rotation

Question 3

Describe the structure & function of intervertebral discs

Answer 3

Annulus fibrosus - fibrous/cartilaginous lamellae, merge with hyaline cartilage
Nucleus pulposus - remnant of the notochord

Allow movement between adjacent vertebral bodies, absorb shock, transmit loads through the vertebral column

Question 4

Recognise the structural & functional characteristics of the joints of the atlas

Answer 4

Atlantooccipitaljoint
- between occipital condoles & cranial articulate cavities of the atlas
- a ginglymus (hinge) joint
- ventral-dorsal extension & flexion (‘yes’ motion)
- strengthened by atlantoocipital membranes & lateral ligaments

Atlantoaxial joint
- between atlas (caudal articular facets & fovea dentis) & axis (cranial articular facets & dens)
- rotational motion (‘no’)
- ligaments secure dens to the ventral arch of the atlas, prevent obstruction to spinal cord

Question 5

List the major ligaments supporting the vertebral column & state their attachments

Answer 5

1. Dorsal longitudinal ligament
   - along dorsal surface of vertebral body
2. Ventral longitudinal ligament
   - along ventral surface of vertebral body
3. Supra spinous ligament
   - joins summits of spinous processes
   (Continues cranially as nuchal ligament)

Question 6

Describe the structural features of a typical rib

Answer 6

• head
• neck
• tubercle
• angle
• body/shaft
• costochondral junction
• costal cartilage

Question 7

Describe the interactions of the ribs with the vertebral column & sternum

Answer 7

Vertebral column:
- Each rib articulates with the cranial part of the respective vertebral body
- tubercle of each rib articulates with the transverse process of respective vertebra

Sternum:
- “true” ribs articulate directly with the sternum
- “false” ribs join to cartilage of next most cranial rib (costal arch)
- “floating” rib unconnected to sternum

Question 8

Give an account of the sternum, comparing its features in different species

Answer 8

Manubrium ← → body ← → xiphoid

Herbivore - manubrium is laterally compressed
e.g. Horse extensive cartilage, ventral keel (boat shaped)
Ruminant wide, flat sternum

Question 9

Recognise the structural & functional characteristics of the joints of the sacroiliac joint

Answer 9

Formed by 1st - 2nd vertebrae of sacrum - auricular surface & the medial aspect of iliac wing (pelvis)

Combined synovial/ fibrous joint