Ch. 7 Axial Skeleton: Vertebral Column

Question 1

How many vertebrae are there? How many of each kind?

Answer 1

26 total vertebrae (33 before fusing)

7 Cervical ("breakfast at 7")
12 Thoracic ("lunch at 12")
5 Lumbar ("supper at 5")

5 sacral: will fuse into 1
4 coccygeal: will fuse into 1

Question 2

What are the 4 functions of the vertebral column?

Answer 2

Protect spinal cord
Support body axis
Attachment points for ribs and muscles of head and neck
Anchor pectoral and pelvic girdles

Question 3

“Typical” Vertebra

Answer 3

Vertebral arch surrounds vertebral foramen

Arch composed of lamina and pedicles

Spinous process and transverse processes are attachment sites for muscles and ligaments

Articular processes and facets are areas where vertebrae articulate (joints)

Vertebral arch/vertebra protects spinal cord and spinal nerves passing through vertebral foramen

Question 4

Vertebral Column and Spinal Cord

Answer 4

Spinal nerves exit between the body of the vertebra and neural arch via intervertebral foramen

Question 5

Laminectomy

Answer 5

Severe spinal/nerve pain - in some cases, the only (or best) option is to remove the lamina of 1 or more vertebrae

Takes pressure off spinal cord and pain is relieved

Question 6

Cervical Vertebrae: C1-C7

Answer 6

Have transverse foramina for blood vessels

• -found in transverse process
• -transverse foramen ONLY found in C vertebrae

Spinous process (often “bifed”/split)

Articular processes and facets face superior/inferior
– look like column in lateral view

Atlas (C1) and Axis (C2) are unusual

Question 7

Atlas

Answer 7

C1

DOES NOT have a body or spinous process

Articulates w/ occipital condyles, allows flexion/extension of head (nodding “yes”)

Question 8

Axis

Answer 8

C2

Dens articulates w/ atlas, allows rotational movement (shaking head “no”)

Has superior and inferior articular facets
–inferior articular facet on inferior side

Question 9

Thoracic Vertebrae: T1-T12

Answer 9

Traverse processes w/ costal facets to articulate w/ tubercle of rib

Costal facets on body for head of rib

Articular processes (facets) - face anterior and posterior

Spinous processes are long and project inferiorly

Costal facets - transverse processes, body (only on thoracic vertebrae)

Question 10

Lumbar Vertebrae: L1-L5

Answer 10

Large bodies (big and robust)
Articular facets face medial/lateral
Short, flat spinous processes

Weight from body focuses here so vertebrae are strong/sturdy

Question 11

Sacrum and Coccyx

Answer 11

Sacrum:

• -5 fused vertebrae
• -forms posterior wall of pelvis
• -Ala (or Alae) on lateral sacrum articulates w/ hip bones to form sacroiliac joints

Coccyx:

• -3-5 fused vertebrae
• -“tail-bone”

Question 12

Curves of the spine

Answer 12

Vertebrae become larger as move inferiorly to support weight

Sacrum articulates w/ hip bones of pelvis, passes weight to appendicular skeleton

Curves increase flexibility; also position center of gravity over axis of body

Cervical curvature: C1-C7
Thoracic curvature: T1-T12
Lumbar curvature: L1-L5
Sacral curvature
Coccyx (4 fused vertebrae)

Question 13

Scoliosis

Answer 13

lateral curvature of spine
–abnormal

usually treated w/ body braces or surgery when young

Question 14

Osteoporosis and Kyphosis (Dowager’s Hump)

Answer 14

Kyphosis is excessive curvature of thoracic spine

Typically result of spinal fractures caused by osteoporosis

Question 15

Lordosis

Answer 15

Lordosis is excessive curvature of lumbar spine

Usually temporary and resulting from shift for a larger load
–ex: pregnancy or beer gut (men)

Question 16

Ligaments and Intravertebral Discs

Answer 16

Lots of ligaments to provide support for vertebrae
Intravertebral discs cushion between vertebrae
Center of intervertebral disc is the nucleus pulpous; outer region is annulus fibrosus