Chapter 1: Back and Autonomic Nervous System

Question 1

During week 4, sclerotome cells of the somites (mesoderm) migrate medially to surround what stuctures?

Answer 1

spinal cord and notochord

Question 2

How many cervical, thoracic, lumbar, sacral, and coccygeal vertebrae are there?

Answer 2

7 cervical, 12 thoracic, 5 lumbar, and fused 5 sacral, and 3-4 coccygeal.

Question 3

Zygapophyseal joints are classified as what type of joints?

Answer 3

synovial joints

Question 4

What structure of the vertebra allows for exit of the spinal nerves?

Answer 4

intervertebral foramina

Question 5

How is each intervertebral disk numbered?

Answer 5

by the vertebral body above the disk

Question 6

What is each intervertebral disk composed of?

Answer 6

anulus fibrosus
nucleus pulposus

Question 7

Anulus fibrosus? Also what is it composed of?

Answer 7

consists of the outer concentric rings of fibrocartilage and fibrous connective tissue

Question 8

Nucleus pulposus?

Answer 8

an inner soft, elastic, compressible material that functions as a shock absorber for external forces placed on the vertebral column

Question 9

Where is herniation of the nucleus pulposus common?

Answer 9

posterolateral direction

Question 10

Anterior longitudinal ligament of the vertebral column?

Answer 10

forms a broad band of fibers that connects the anterior surfaces of the bodies of the vertebrae between the cervical and sacral regions.

prevents hyperextension of the vertebrae and is involved in “whiplash” accidents

Question 11

Posterior longitudinal ligament of the spinal column?

Answer 11

connects the posterior surfaces of vertebral bodies and is located in the vertebral canal

limit flexion of the vertebral column

Question 12

What does the vertebral (foramen) canal house?

Answer 12

spinal cord

Question 13

The nucleus pulposus may herniate through what structure and lead to what?

Answer 13

herniate through the anulus fibrosus

herniated nucleus pulposus may. compress the spinal nerve roots, resulting in pain along the involved spinal nerve (sciatica)

Question 14

What area of the spinal cord does herniation of the nucleus pulposus typically occur? (What levels)

Answer 14

lower cervical (C5/C6 or C6/C7) or lower lumbar (L4/L5 or L5/S1) parts of the vertebral column

Question 15

Herniated disk will usually compress what spinal nerve roots? (herniated nucleus pulposus)

Answer 15

the nerve roots one number below involved disk (e.g herniation of L4 disk will compress the L5 roots)

This is the same for cervical nerve roots except thoracic in which the thoracic herniation will corresponnd with upper vertebral level above it

Question 16

What are the boundaries of the intervertebral foramina?

Answer 16

anterior: bodies of the vertebrae and intervertebral disks

posterior: zygapophyseal joint and articular processes

superior and inferior: pedicles of the vertbrae

Question 17

Dura mater?

Answer 17

cylindrical covering of connective tissue forming a dural sac

Question 18

Where do the dura mater and dural sac terminate in the spinal cord?

Answer 18

inferiorly at the second sacral vertebra level

Question 19

Describe the arachnoid.

Answer 19

delicate membrane which completely lines the inner surface of the dura mater and dural sac

Question 20

Where does arachnoid terminate in the spinal cord?

Answer 20

terminates at the second sacral vertebra

Question 21

What is pia mater?

Answer 21

tightly attached to surface of the spinal cord and provides a delicate covering of the cord

Question 22

Where does the spinal cord with the covering of the pia mater terminate?

Answer 22

at the L1 or L2 vertebral levels in the adult

Question 23

What are the 2 specializations of the pia mater?

Answer 23

denticulate ligaments and filum terminale

Question 24

What are the denticulate ligaments?

Answer 24

bilateral thickenings of pia mater that run continuously on the lateral sides of the midpoint of the cord

separate the ventral and dorsal roots of the spinal nerves and anchor to the dura mater

Question 25

What is the filum terminale?

Answer 25

a continuation of the pia mater distal to the lower end of the spinal cord and is part of the cauda equina which is composed of ventral and dorsal roots of lumbar and sacral nerves that extend below the inferior limit of the spinal cord

Question 26

The internal vertebral venous plexus is valveless and connects what structures?

Answer 26

veins of the pelvis, abdomen, and thorax

Question 27

What is a clinical correlation to remember related to the fact that the internal vertebral venous plexus is valveless?

Answer 27

provides a route of metastasis

Question 28

Where is the epidural space located?

Answer 28

between the inner walls of the vertebral canal and dura mater

Question 29

What does the epidural space contain?

Answer 29

fat and the internal vertebral venous plexus

Question 30

The internal vertebral venous plexus continues superiorly through the foramen magnum to connect with what veins cranial cavity?

Answer 30

dural venous sinuses

Question 31

Where is the location of the subarachnoid space?

Answer 31

pressurized space located between the arachnoid and pia mater layers

Question 32

What does subarachnoid space contain?

Answer 32

cerebrospinal fluid (CSF)

Question 33

Where does the subarachnoid space terminate?

Answer 33

at the second sacral vertebral level

Question 34

What is the inferior limit of the spinal cord?

Answer 34

L1 or L2 vertebrae in adults (conus medullaris)

Question 35

What is the inferior limit of the dural sac and the subarachnoid space?

Answer 35

S2 (CSF)

Question 36

Dorsal ramus supplies what area of the body?

Answer 36

skin of back and dorsal neck deep intrinsic back muscles (Erector spinae)

Question 37

Ventral ramus supplies what area of the body?

Answer 37

skin of anterolateral trunk and limbs sk. muscles of anterolateral trunk and limbs

Question 38

Each spinal n. is formed by the union of what 2 nerve roots?

Answer 38

dorsal root ventral root

Question 39

What does the dorsal root carry?

Answer 39

sensory fibers from the periphery into the dorsal aspect of the spinal cord

Question 40

Dorsal root ganglion?

Answer 40

on each dorsal root there is a DRG (sensory) containing the pseudounipolar cell bodies of nerve fibers that are found in the dorsal root

Question 41

Ventral root?

Answer 41

arises from the ventral axon of spinal cord and carries axons of motor neurons

Question 42

Spinal n.

Answer 42

formed by union of ventral and dorsal roots; and exit the vertebral column by passing through the intervertebral foramen

Question 43

Dorsal rami innervate what areas of the body?

Answer 43

innervate the skin of the dorsal surface of back, neck (including zygapophyseal joints, and intrinsic sk. muscle of the deep back)

Question 44

Ventral rami? (What does it innervate is the question)

Answer 44

innervate skin of the anterolateral trunk and limbs and the sk. muscles of the anterolateral trunk and limbs (ventral rami form the brachial and lumbosacral plexuses

Question 45

All nerves beginning with T1 and below will exit the intervertebral foramina (inferior or superior) to the pedicle of the same-numbered vertebrae?

Answer 45

inferior

Question 46

The cervical nerves C1 - C7 exit the intervertebral foramina (superior or inferior) to the pedicles of the same-numbered vertebrae?

Answer 46

superior to C8 n exits intervertebral foramen inferior to the C7 pedicle | Answer may be inferior for all check

Question 47

What is lumbar puncture?

Answer 47

used to inject anesthetic material in the epidural space or to withdraw CSF from the subarachnoid space

Question 48

Where is a spinal tap typically performed? (levels)

Answer 48

L4-L5 interspace

Question 49

How do you find the L4 vertebra?

Answer 49

a horizontal line drawn at the top of the iliac crest marks the level of L4

Question 50

When a lumbar puncture is performed in the midline, the needle passes through what part of the vertebral column?

Answer 50

interlaminar space found between the lamina of the lumbar vertebrae

Question 51

What are the interlaminar spaces covered by?

Answer 51

highly elastic ligamenta flava

Question 52

What section of the spinal cord are the preganglionic cell bodies of the sympathetic nervous system found? Be specific.

Answer 52

lateral horn gray matter of the spinal cord segments T1 - L2 (thoracolumbar)

Question 53

Where are the postganglionic cell bodies of the sympathetic nervous system found?

Answer 53

chain or paravertebral collateral or prevertebral or preaortic (found when traveling to abdomen or pelvis)

Question 54

Lesions at the superior cervical ganglion, middle cervical ganglion and cervicothoracic ganglion can lead to what syndrome?

Answer 54

Horner's syndrome

Question 55

What are the CN that the parasympathetic nervous system innervates?

Answer 55

CN III, VII, IX and X

Question 56

CN III gives synapses at what ganglion? (for parasympathetic innervation)

Answer 56

ciliary ganglion

Question 57

What does the ciliary ganglion innervate?

Answer 57

pupillary sphincter ciliary m.

Question 58

What parasympathetic innervated ganglion does CN VII connect to?

Answer 58

submandibular ganglion and pterygopalatine ganglion

Question 59

Parasympathetic innervation through the submandibular ganglion gives innervation to what structures?

Answer 59

submandibular gland and sublingual gland

Question 60

Parasympathetic innervation through the pterygopalatine ganglion innervates what structures?

Answer 60

lacrimal gland, nasal and oral mucosal glands

Question 61

Parasympathetic innervation through CN IX synapses with what ganglion?

Answer 61

otic ganglion

Question 62

Otic ganglion parasympathetic innervation goes to what structures?

Answer 62

parotid gland

Question 63

CN X innervates what structures? (parasympathetics)

Answer 63

synapses on or near terminal ganglia to viscera of neck, thorax, foregut, and midgut

Question 64

Pelvic splanchnic nerves S2, S3, S4 innervate what structures? (parasympathetic)

Answer 64

hindgut and pelvic viscera (including the bladder, rectum, and erectile tissue

Question 65

During a lumbar puncture, a needle is passed through the interlaminar space while the vertebral column is flexed or extended?

Answer 65

flexed

Question 66

The needles pass through what structures during a lumbar puncture if trying to collect CSF?

Answer 66

* skin * superficial fascia * deep fascia * supraspinous ligament * interspinous ligament * interlaminar space * epidural space * dura * arachnoid * subarachnoid space