Lecture 6 - ANP1106

Question 1

Typical Vertebrae

Answer 1

Gets larger as one descends column – Larger further down to compensate for the increased weight above it for adequate support

Formed of a weight-bearing body & vertebral arch (2 pedicles with notches on superior & inferior surfaces forming the intervertebral foramina between adjacent vertebrae for passage of nerves and 2 laminae) which enclose the vertebral foramen containing the spinal cord of the CNS

Question 2

What are the 7 processes that emerge from each vertebral arch ?

Answer 2

• 1 spinous process for muscle attachment
• 2 transverse processes (1 per side) for muscle attachment
• Paired superior + inferior articular processes with facets covered in hyaline cartilage for smooth articulation of adjacent vertebrae

Question 3

Cervical Vertebra - Vertebrae 1 & 2

Answer 3

Vertebrae 1 – Atlas
Vertebrae 2 – Axis

• Have NO intervertebral disc
• Have an unusual structure

Atlas [ supports the skull ] – Has NO body & NO spinous process but has posterior + anterior arches extending from lateral masses containing superior articular facets for articulation with the occipital condyles (of the occipital bone) & inferior articular facets for articulation with the axis (fits with the axis’ inferior articular facets)

Axis – Shape intermediate between the atlas and a typical vertebrae but with a dens (odontoid process) which allows rotation of the head left / right

Question 4

Cervical Vertebra - Vertebrae 3 - 7

Answer 4

• More typical but with spinous processes that are short & split at the end
• Except C7 which is long & non-split (the first vertebrae u can feel / be palpated – can serve as a reference point) & each transverse process contains a transverse foramen for passage of the vertebral artery to the brain

Question 5

Thoracic Vertebrae

Answer 5

• Body has demi-facets for articulation on adjacent vertebrae for the head of ribs
• Transverse processes have facets for articulation with the tubercles of ribs (except thoracic vertebrae 11 & 12)
• Spinous process is long + angled caudally (downwards)

superior -inferior

Question 6

Lumbar Vertebrae

Answer 6

• Pedicles & laminae are shorter and thicker
• Spinous processes are flat, short, and project directly back
• Inferior facets are oriented laterally while superior facets are oriented medially

lateral-medial

Question 7

Sacral Vertebrae

Answer 7

5 separate sacral vertebrae are fused during adolescence (transverse lines indicate where adjacent vertebrae fused) into the sacrum with a sacral canal for the nervous tissue

• Sacrum articulates superiorly with the 5th lumbar vertebra and laterally with the hip bones (at the sacroiliac joint)
• Sacral promontory is a ridge found at the antero-superior aspect of the sacrum
• Sacral foramina are the equivalent of intervertebral foramina for the passage of nerves
• Median sacral crest is a dorsal midline ridge of bone formed by the fusion of the spinous processes
  Sacral hiatus is a caudal opening of vertebral canal

Question 8

Coccygeal Vertebrae

Answer 8

• Forms the tailbone from fusion of the 3-4 coccygeal vertebrae

Question 9

What is the thorax / thoraccic cage ?

Answer 9

Formed of thoracic vertebrae, ribs, costal cartilage, and the sternum to form a protective cage around the heart, lungs and major blood vessels

• Provides support for the shoulder girdle and upper limbs, and provides surface area for attachment of back, chest and shoulder muscles

Question 10

The sternum is ________ & _______ in the thorax and is formed from the fusion of 3 bones :

Answer 10

anterior & midline

• Manubrium at the top (articulates with 1st pair of ribs and clavicles via clavicular notches)
• Body (has notches for articulation with ribs 2-7)
• **Xiphoid **process (attachment for some muscles) of the sternum

Question 11

What are 3 important anatomical landmarks of the sternum ?

Answer 11

• Jugular notch which is the superior border of the manubrium that is aligned with T2-T3
• Sternal angle which is the cartilaginous hinge between the manubrium and body of sternum
• Xiphisternal joint which is the fusion of the sternal body with the xiphoid process (aligned with T9)

Question 12

What are the ribs of the sternum ?

Answer 12

There are 12 ribs per side, all attached at the back to the vertebral column, and curve inferiorly and anteriorly
- 7 are true ribs that attach to the sternum independently
- 5 are false ribs with ribs 8-10 attaching to the sternum indirectly via costal cartilages and rib 7 while ribs 11 and 12 are not attached anteriorly (floating ribs)