Vertebral Column and Spinal Cord

Question 1

Joints of vertebral column

Answer 1

Craniovertebral Joints
1. Atlanto-occipital: between C1 and occipital
2. Atlanto-axial: C1 + C2
Joints of Articular Processes
3. Zygapophysial
Joints of Vertebral Bodies
4. Unconvertebral
5. Intervertebral

Question 2

Intervertebral Joints

Answer 2

Between Intervertebral discs and the vertebral body

Question 3

What is the intervertebral disc composed of?

Answer 3

-Annulus Fibrosus
-Nucleus pulposus

Question 4

What is a herniation, and where is it most common?

Answer 4

When a portion of the nucleus pulposus is pushed through a weakened portion of the annulus fibrosis
-Herniation is most common posteriolaterally at L4-L5 and L5-S1, no PLL or ALL

Question 5

Ligamenta Flava

Answer 5

Def: connects adjacent laminae of vertebrae
a. Limits flexion
b. Clinically significant (epidural)

Question 6

Anterior Longitudinal Ligament (ALL)

Answer 6

anterior bodies and IV discs from skull to sacrum
a.Prevents hyperextension
(bigger one)

Question 7

Posterior Longitudinal Ligament (PLL)

Answer 7

posterior bodies and IV disc from C2 to sacrum within spinal canal
a.Prevents hyperflexion
(smaller one)

Question 8

Nuchal Ligament

Answer 8

provides attachment site for cervical muscles
a.Resists flexion

Question 9

Supraspinous Ligament

Answer 9

connects tips of spinous processes
a.Limits hyperflexion

Question 10

Intraspinous Ligament

Answer 10

connects adjacent spinous processes
a.Limits hyperflexion

Question 11

“Whiplash” Injury

Answer 11

oA strain or muscle injury of the neck due to sudden hyperextension and possible hyperflexion as head rebounds
oPossible stretching or even tearing of anterior longitudinal ligament (ALL)
oPossible “facet jumping” or locking of cervical vertebrae due to arch dislocation

Question 12

Neck Injuries

Answer 12

oIllegal face blocking causes hyperextension and will likely injure posterior portions of the vertebrae
oT11/T12 most common non-cervical break

Question 13

Order of Spinal Cord Meninges

Answer 13

-Epidural space, dura mater, subdural space, arachnoid mater, subarachnoid space, pia mater

Question 14

Epidural space

Answer 14

o Between dura mater and inner walls of the vertebra
o Contains far and blood vessels

Question 15

Dura Mater

Answer 15

o Most external of the meninges
o Fuses with epineurium that surround that spinal nerves

Question 16

Subdural space

Answer 16

o Separates the dura mater from the arachnoid mater
o This is a potential space

Question 17

Arachnoid mater

Answer 17

o Located deep to the dura mater and subdural space

Question 18

Subarachnoid space

Answer 18

o REAL space
o Filled with CSF

Question 19

Pia Mater

Answer 19

o Adheres directly to the spinal cord
o Forms lateral extensions called denticulate ligaments
 Suspend and anchor the spinal cord laterally to the dura mater

Question 20

Spinal Cord

Answer 20

-Protected by vertebrae, ligaments, and muscles, spinal meninges, and CSF
-Continuation of the medulla oblongata
-Extends from foramen magnum to approx. T12-L3 in adults (Avg: L1)
-31 pairs of spinal nerves:
o Cervical (C1-C8)
o Thoracic (T1-T12)
o Lumbar (L1-L5)
o Sacral (S1-S5)
o Coccygeal (Co1)
-Cervical (C4-T1) and Lumbar (L1-S3) enlargement (significant number of motor neurons exiting

Question 21

Sclerotome Resegmentation

Answer 21

8 cervical sclerotomes–> 7 cervical vertebrae, 8 cervical spinal nerve pairs

Question 22

Anterior (ventral) root

Answer 22

contains only motor axons

Question 23

Posterior (dorsal) root

Answer 23

contains only sensory axons

Question 24

Dorsal Root Ganglion

Answer 24

contains cell body for sensory neurons

Question 25

Spinal nerve

Answer 25

The anterior and posterior roots unite within intervertebral foramen to become a spinal nerve

Question 26

Posterior (dorsal) ramus

Answer 26

a.Inn: Intrinsic (deep) muscles of the back
b.Carries sensory from the skin of the back

Question 27

Anterior (ventral) ramus

Answer 27

a.Inn: anterior and lateral portions of the trunk (intercostal nn.) upper and lower limbs
b.Carries sensory from the associated skin
c.Larger than posterior

Question 28

Arterial supply of spinal cord

Answer 28

-Vertebral and ascending cervical arteries (aa.)
-Major segmental aa:
oPosterior intercostal aa. In the thorax
oSubcostal and lumbar aa. In the abdomen
oIliolumbar, lateral and medial sacral aa. in pelvis
-Spinal arteries pass through the intervertebral foramina then divide into anterior and posterior branches

Question 29

Venous drainage of spinal cord

Answer 29

-3 anterior and 3 posterior veins (vv.) run longitudinally: drains into internal vertebral plexus in epidural space
-Spinal veins (vv.) form internal and external venous plexus
-Plexuses communicate through the intervertebral foramina
-Spinal cord and vertebral venous plexus drain into intervertebral vein which drains to:
oVertebral veins in the neck
oSegmental veins in the trunk (posterior intercostal, lumbar, and sacral)

Question 30

Conus medullaris

Answer 30

tapering inferior end of the spinal cord

Question 31

Cauda equina

Answer 31

bundle of nerve roots running inferior to the spinal cord

Question 32

Filum terminale

Answer 32

thin strand of pia mater that helps anchor the conus medullaris to the coccyx

Question 33

Lumbar puncture

Answer 33

to obtain CSF
oDrawn from subarachnoid space, constantly being produced, L4/L5 (posterior iliac spines- PSIS as landmarks for lumbar puncture)
oNo agent in here- if put in will be gone ASAP as it will be pumped out quickly

Question 34

Epidural

Answer 34

injection of anesthetic agent into the epidural space, where there is direct effect on the spinal nerve roots and cauda equina
oEpidural space is fat filled and includes spinal nerve segments, able to keep a drug present for awhile

Question 35

Laminectomy

Answer 35

-Option to relieve spinal stenosis
-Relieves pressure within intervertebral column
-Most common cause of narrowed vertebral column is bony outgrowths