MSK 06 - Vertebral Column & Spinal Cord

Question 1

How many vertebra (fused and unfused) are there in each region of the vertebral column?

Answer 1

Question 2

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Question 3

Descirbe the regional uniqueness of the vertebrae.

Answer 3

Question 4

What are the atypical vertebrae and what makes them atypical?

Answer 4

C1 (atlas) - has no body or arch and possesses a largern than normal superior articular facet

C2 (axis) - Has the Dens (odontoid process)

Sacrum - has wings and transverse ridges

Coccyx - short and curved

Question 5

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Question 6

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Question 7

How many spinal ligaments are they? Describe what they connect.

Answer 7

5 spinal ligaments

Anterior longitudinal ligament - runs down the anterior surface of the spine. It traverses all of the vertebral bodies and intervertebral discs

Posterior longitudinal ligament - situated within the vertebral canal, and extends along the posterior surfaces of the bodies of the vertebrae

Ligamentum flavum - connect the laminae of adjacent vertebrae

Interspinous ligament - connect adjoining spinous processes

Supraspinous ligament - connects the tips of the spinous processes from C7 to the sacrum

Question 8

Answer 8

Question 9

What is a cruciate ligament?

Answer 9

A cruciate ligament is a pair of ligaments arranged like a letter X.

Question 10

Describe the joints and ligaments of the C1 and C2 vertebrae.

Answer 10

• During rotation of the head, the dens (C2) is the axis that is held in a socket formed by the anterior arch of C1 and the transverse ligament of the atlas
• Vertically oriented but much weaker superior and inferior longitudinal bands of ligament pass from the transverse ligament to the occipital bone superiorly and to the body of C2 inferiorly
• The transverse ligament and longitudinal bands together are referred to as the cruciate ligament
• An apical ligament deep to the cruciate ligament helps to attach the dens to the skull superiorly while the alar ligaments attach the dens to the skull laterally

Question 11

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Question 12

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Question 13

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Question 14

What are the primary and secondary spinal curvatures and when and why do they develop?

Answer 14

Question 15

List and briefly describe the abnormal spinal curvatures.

Answer 15

Kyphosis (hunchback) - an increase in the thoracic spinal curvature, as a result the vertebral column curves posteriorly

Lordosis - characterized by an anterior tilting of the pelvis (the upper sacrum is flexed or rotated antero-inferiorly) with increased extension of the lumbar vertebrae, producing an abnormal increase in the lumbar kyphosis

Scoliosis - characterized by an abnormal lateral curvature that is accompanied by rotation of teh vertebrae

Question 16

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Question 17

Where are the spinal cord enlargements and tapers?

Answer 17

Question 18

Where/what is the cona medularis?

Answer 18

It is the tapered, lower end of the spinal cord. It occurs near lumbar vertebral levels 1 (L1) and 2 (L2), occasionally lower.

Question 19

What are spinal meninges? List them and the correlating spaces from outer to inner.

Answer 19

Epidural Space

Dura mater

Subdural space

Arachnoid mater

Subarachnoid space

Pia mater

Question 20

Answer 20

Question 21

Facts to know about denticulate ligaments

Answer 21

• 21 pairs of them (one on either side of the spinal cord) connected by a single narrow fibrous strip
• Extend from the craniovertebreal junction to T12
• Each ligament has 18-20 triangular extensions of pia mater that attach to the dura at their apices
• They separate the ventral and dorsal rootlets from each other

Question 22

Answer 22

Question 23

How does the position of the caudal end of the spinal cord change from 8 weeks (gestational) to adult?

Answer 23

8 weeks - end of coccyx

24 weeks - S1

Newborn - L3

Adult - L1

Question 24

What is the cauda equina and filum terminale?

Answer 24

Cauda Equina - a bundle of spinal nerves and spinal nerve rootlets, consisting of the second through fifth lumbar nerve pairs, the first through fifth sacral nerve pairs, and the coccygeal nerve, all of which arise from the lumbar enlargement and the conus medullaris of the spinal cord.

Filum terminale - a delicate strand of fibrous tissue, about 20 cm in length, proceeding downward from the apex of the conus medullaris. It is one of the modifications of pia mater

Question 25

What purpose does the filum terminale serve?

Answer 25

It gives longitudinal support to the spinal cord

Question 26

What is the dural sac?

Answer 26

It is the membranous sheath of dura mater that surrounds the spinal cord, cauda equina, dorsal & ventral roots, and the filum terminale (until the S2 level).

Question 27

At what vertebral level does the spinal cord, dural sac, and filum terminale end?

Answer 27

L1, S2, and the coccyx respectively

Question 28

Answer 28

Question 29

What arteries can cause spinal cord circulatory impairment is their flow is interrupted?

Answer 29

The segmental medullary arteries, particularly the great anterior segmental medullary artery (of Adamkiewicz).

Question 30

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Question 31

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Question 32

How is a lumbar puncture performed? What are the key signs to look for to ensure proper needle placement? When is an LP not performed?

Answer 32

Question 33

What does a needle pass through during an LP?

Answer 33

Skin, subcutaneous tissue, supraspinous ligament, interspinous ligament, ligamentum flavum, epidural space, dura mater, arachnoid mater, subarachnoid space