MS1 Spinal Cord and Spinal Nerves Flashcards
(123 cards)
1
Q
What are the components of the CNS
A
brain and spinal cord
2
Q
What are the components of the PNS
A
cranial and spinal nerves, ganglia, and associated terminals (motor endings and sensory receptors)
3
Q
Where is the spinal cord found
A
within the vertebral column
4
Q
What is the function of the spinal cord
A
allows communication between brain and body, conducts reflexes as part of the CNS
5
Q
What is the positioning of the spinal cord within the vertebral canal
A
The spinal cord is shorter than the vertebral column
6
Q
What causes the spinal cord to be shorter than the vertebral column
A
differential growth
the vertebral canal grows faster than the spinal cord
7
Q
Where will the spinal cord end in adults
A
L1-L2
8
Q
Where will the spinal cord end in infants
A
L3-L4
9
Q
How many nerve pairs are found in each segment of the spinal cord
A
Cervical 8 Thoracic 12 Lumbar 5 Sacral 5 Coccygeal 1
10
Q
What are the two enlargements of the spinal cord
A
cervical enlargement and lumbar enlargement
11
Q
What is the cervical enlargement
A
Innervation to the upper limb C5-T1
12
Q
What is the lumbar enlargment
A
L1 to S3, innervation to the lower leg
13
Q
What is seen beyond the lumbar enlargment
A
spinal cord tapers to form conus medullaris
14
Q
What is gray matter composed of
A
cell bodies of motor neurons in the spinal cord
15
Q
What is white matter
A
axons of sensory neurons in the spinal cord
16
Q
What is contained within the anterior horn of the spinal cord
A
Cell bodies of GSE neurons that will travel through the anterior root
17
Q
What is found in the DRG
A
cell bodies of sensory neurons through the posterior root
18
Q
What is the conus medullaris
A
tapered termination of spinal cord past the lumbar enlargement
19
Q
Where is the conus medullaris found
A
L1-L2
20
Q
What is the cauda equina
A
inferior projection from conus medullaris composed of lumbar and sacral roots to the lower limbs, buttocks, and perineum
21
Q
What is the conus medularis surrounded by
A
CSF
22
Q
Where is the conus medularis housed
A
lumbar cisterne
23
Q
How are spinal nerves named
A
Cervical: based on the vertebral body number below, except for C8 (exit above vertebrae, except C8)
Thoracic and Lumbar are named for vertebral body above (exit below vertebrae)
24
Q
What spinal level will be affected by a posterolateral herniation
A
The spinal cord level below where the herniation occurs
25
What spinal level will be affected by a lateral herniation
THe spinal cord level at where the herniation occurs
26
WHy do posterolateral herniations impact the nerve exiting below
spinal nerves hug a pedicle of the corresponding vertebrae as they exit through the intervertebral foramen
27
What do vertebral arteries contribute to the spinal cord
anterior and posterior spinal arteries
28
What do body wall arteries (from aorta) give rise to
segmental spinal arteries
29
What do the segmental arteries give rise to
segmental medullary arteries
anterior and posterior radicular arteries
30
What are segmental medullary arteries
feed spinal arteries 8-10
31
What are anterior and posterior radicular arteries and where are they located
every level, and supply roots
32
What is the artery of Adamkiewicz
segmental medullary artery, major supply of blood to lower spinal cord
33
Why is the artery of Adamkiewicz significant from a clinical standpoint
it comes from the left and is at risk during hernia repair and abdominal surgeries
34
What occurs if the artery of Adamkiewicz is damaged
leads to weakness and sensory loss in the lower limbs
35
What is the clinical significance of venous drainage of the spinal cord and vertebral column
valveless and allows easy spread of cancer cells
36
What composes the venous drainage system of the spinal cord
anterior/posterior spinal veins
internal vertebral plexus
intervertebral veins
37
Where is the internal vertebral plexus located
in the epidural space
38
What is the venous system of the vertebral columns
basivertebral veins
| external vertebral plexus
39
Where are the basivertebral veins
in the vertebral bodies
40
Where are the anterior and posterior spinal veins
they go to the anterior and posterior roots of the spinal nerve
41
What are the meninges found on the spinal cord
dura mater
arachnoid mater
pia mater
42
What do the lateral extensions of the dura mater enclose
proximal portion of spinal nerve
43
What is the name for the dura mater that covers the proximal portion of spinal nerve
dural root sheaths
44
Where do the dural root sheaths go
merge with epineurium
45
What are the attachments of the dura mater
foramen magnum and vertebral bodies of C2-C3
inferiorly ends at S2
46
What type of structure does the dura mater have
dense elastic membrane
47
Does the dura mater receive blood supply and innervation
yes
48
What is the structure of the arachnoid mater
delicate fibrous and elastic membrane
49
What connects the dura mater to the arachnoid mater
pressed against by the pressure of CSF
50
Where does the arachnoid mater extend to
extends to S2
51
What does the arachnoid mater do at S2
lines the dural sac and dural root sheaths
52
Where are arachnoid trabeculae found
In the subarachnoid space
53
What are the meningeal spaces
subarachnoid
subdural space
epidural space
54
Where is the epidural space
between bone and dura
55
Is the epidural space a real or potential space
real
56
What is another name for the epidural space
extradural space
57
Where is the subdural space
between dura and arachnoid mater
58
Is the subdural space real or potential
potential
59
Where is the subarachnoid space
between arachnoid and pia mater
60
Is the subarachnoid space real or potential
real
61
What meningeal layer has denticulate ligaments
pia mater
62
What is the function// structure of denticulate ligamaments
lateral extensions that anchor spinal cord to dura mater
63
Describe the structure of the pia mater
thin transparent membrane that is vascular tissue
64
Where is the pia mater located
invests brain and spinal cord, directly covers spinal nerves
65
What is the filum terminale
pia mater exension that tethers the tip of the conus medullaris to the end of the sacrum
66
When will filum terminale be invested in dura mater
S2
67
What does the filum terminale become at S2
filum terminale externum
68
What does the filum terminale externum do
descend to coccyx anchoring the spinal cord to the dural sac
69
What is thethered cord syndrome
filum terminale is too short or there is something restricing its growth, sitting too low in the can, tension
70
What layers need to be crossed to do a lumbar puncture
skin, superficial fascia, thoracolumbar fascia, erector spinae, multifidus, rotatores, interspinous ligament, supraspinous ligament, ligamentum flavum, epidural space, dura mater, arachnoid mater
71
What are the two pops heard in a lumbar puncture
pop through ligamentum flavum and dura mater
72
What is the functional unit of the nervous system
neuron
73
What is a neuron composed of
cell body, dendrites, axon
74
How does a neuron receive and transmit information
receives info from other cells through dendrite
| sends information to other cells through axon
75
What are the different types of neurons
bipolar
pseudopolar
multipolar
76
What are usually multipolar neurons
motor or interneurons
77
What are bipolar neurons
special sensory
78
Where are bipolar neurons typically found
retina and CN VIII
79
What are usually uni/pseudopolar neurons
sensory
80
Where are sensory neuron cell bodies usually found
in ganglia
81
What are collections of neuronal cell bodies called in the CNS and PNS
ganglia in PNS
| gray patter in CNS
82
What are bundles of axons called in CNS and PNS
white matter in CNS
| PNS: root, ramus, nerve
83
How will afferent signals move
towards CNS
84
What are afferent signals
sensory
85
How will effernt move
away from CNS
86
What are efferent signals
motor
87
What is general innervation
touch, pressure, proprioception, vibration, pain and temperature
88
What is somatic innervation
body wall
89
What is visceral innervation
smooth and cardiac muscle, glands, and erector pilli
90
What are GSE neurons
general somatic efferent
91
Where do GSE neurons go, what type of neuron, and what signal
to the body wall, motor, multipolar
92
Where do GSA go, what type of neuron, and what signal
from body wall, sensory, pseudounipolar
93
Where do GVE go, what signal and what type of innervation
to viscera, motor, autonomic innervation
94
Where do GVA go and what signal type
viscera, sensory
95
Where are the cell bodies of GSE
anterior horn of spinal cord
96
How do GSE fibers run to innervate body
out anterior root
go to spinal nerve
split between anterior and posterior rami
97
What type of info is carried in the anterior root
motor (GSE, GVE)
98
What type of info is carried in the posterior root
sensory (GSA, GVA)
99
What information is carried in a spinal nerve
motor and sensory
100
What information carried in the posterior and anterior rami
motor and sensory
101
What are the nerve plexuses discussed
lumbar and brachial
102
What is the organization of a nerve and their related connective tissues
endoneurium around a single axon
perineurium around fascicle
epineurium coating around whole nerve
103
What is a dermatome
area of skin innervated by a single spinal cord level
104
What provides sensation to the posterior aspect of the neck and trunk
posterior rami
105
What is a myotome
muscles innervated by a single spinal cord level
106
What is neuropathy
pathology of a peripheral nerve
107
What will neuropathy affect
structures the nerve innervates, not whole dermatome and myotomes
108
What is radiculopathy
pathology of a spinal nerve or an anterior root
109
What will radiculopathy affect
myotome or dermatome
110
the cervical enlargment of the spinal cord is due to what structure
brachial plexus
111
The lumbar enlargement of the spinal cord is due to what structure
lumbar plexus
112
What is contained within the subarachnoid space
CSF, blood vessels, and CT
113
where do 95% of disc herniations occur
L4-L5, or L5-S1
114
WHen should an epidural not be performed
if you have a fresh tattoo in that area
115
WHere is a lumbar puncture performed
above or below L4-L5 spinous process
116
Is lumbar puncture safe in newborns
yes
117
When should a lumbar puncture not be performed
when someone has cranial pressure as this will cause cranial herniation
118
What are the segmental spinal arteries that are from certebral artery
variable segmental medullary arteries
anterior radicular
posterior radicular
119
What plexus is a big role in metastasis of prostate cancer
basins plexus in vertebral venous system of internal venous plexus
120
What is varicella zoster
chicken pox or shingles
121
In shingles, how do we see lesions appear
along the dermatome
122
Why does shingles follow the dermatome
infection is inside that spinal nerve level on one side
123
What is a sclerotome
innervation of skeletal bones and cells
