Peripheral Nervous System Flashcards
(158 cards)
1
Q
How many levels in the thoracic spinal cord
A
12
2
Q
How many levels are in the lumbar spinal cord
A
Five
3
Q
How many levels are in the sacral spinal cord
A
Five
4
Q
What is the conus medullaris
A
The most inferior caudal part of the spinal cord
5
Q
What vertebral level is the conus medullaris at
A
Between L1 and L2
6
Q
What are the two spinal cord enlargements
A
The cervical enlargement
the lumbosacral enlargement
7
Q
What does the cervical enlargement control
A
Upper extremities
8
Q
What does the lumbosacral enlargement control
A
Lower extremities
9
Q
Is the Rostro spinal cord or the coddle spinal cord bigger
A
Rostral
10
Q
What do the peripheral nerve supply
A
Either the viscera or somatic structures
11
Q
What does the somatic peripheral nerves include
A
Sensory autonomic and motor axons
12
Q
What to cutaneous branches of peripheral nerve supply
A
The skin and subcutaneous tissues
13
Q
What are peripheral axons classified according to
A
Speed of conduction and diameter
14
Q
What are the components of peripheral nerves
A
Neural components
Glial components
connective tissue components
15
Q
What did the neural components of peripheral nerves contain
A
Axons
16
Q
What did the glial components of peripheral nerves contain
A
Schwan cells
17
Q
What are the connective tissue components of peripheral nerves
A
The endoneurium
perineurium
epineurium
18
Q
What do connective tissue components in the peripheral nerves have a role in
A
How nerves work and how they recover
19
Q
What does the endoneurium do
A
Surrounds each individual axon
20
Q
What does the perineurium do
A
Surrounds bundles of axons
21
Q
What does the epineurium do
A
Surrounds all the bundles
22
Q
What do the sensory components of cutaneous branches of peripheral nerves do
A
Go to receptors e.g. touch pain vibration etc.
23
Q
What do the motor components of cutaneous branches do
A
Supply blood vessels sweat glands and hair on the skin
24
Q
What do you cutaneous branches of peripheral nerves go to
A
The skin
25
What do muscular branches of peripheral nerves go to
Skeletal muscle and nerves ligaments tendons
26
What are nerve plexuses
Junctions of anterior rami from four nerve plexuses
27
What are the four nerve plexuses
Cervical
brachial
lumbar
sacral
28
Where is the cervical nerve plexuses between
C-1 through C4
29
Where is the brachial nerve plexuses between
C5 to T1
30
What does the brachial nerve plexuses control
Upper extremities
31
Where is the lumbar nerve plexuses between
L1 to L4
32
What does the lumbar nerve plexuses control
Anterior and medial thigh
33
Where is the sacral nerve plexus says between
Part of L4
| between L5 to S4
34
What does the sacral nerve plexuses control
Posterior thigh and leg
35
What does the cervical plexus provide
Cutaneous sensory information from the posterior scalp to the clavicle
Control sensation in the neck
36
What does the cervical plexus innervate
The anterior neck muscles and diaphragm
37
What does the brachioplexus innervate
The entire upper limb
38
What does the lumbar plexus innervate
The skin and muscles of the anterior and medial thigh
39
What does the sacral plexus innervate and what does it contain
The posterior thigh and most of the leg and foot and sciatic nerve
Parasympathetic axons
40
What is a dermatome
An area of skin innervated by one spinal nerve
41
What is a dermatome for the face
The trigeminal nerve
42
What is the dermatome for the remainder of the head
C2
43
What is the dermatome for the nipple line
T4
44
What is the dermatome for the umbilicus
T10
45
What is a dermatome for the top of the shoulder
C-4
46
What is a dermatome for the shoulder and lateral arm
C-5
47
What is a dermatome for the lateral forearm and the first two digits
C6
48
What is the dermatome for the middle digit
C7
49
What is the dermatome for the fourth and fifth digits
C8
50
What is the dermatome for the medial arm and forearm
T1
51
What is the dermatome for the anterolateral thigh
L2
52
What is the dermatome for the anteromedial thigh and knee
L3
53
What is the dermatome for the anteromedial shin
L4
54
What is a dermatome for the anterolateral shin and top of the foot to the big toe
L5
55
What is the dermatome for the small toe lateral foot sole and calf
S1
56
What is the dermatome for the perineal region
S2 S3 S4
57
What are myotomes
Muscles innervated by a single nerve root
58
Where are disc herniations most common
In the cervical and lumbosacral levels
59
In disc herniations the nerve root that is involved usually corresponds to
The lower of the adjacent two vertebrae
60
In the cervical level where do spinal nerves exit the vertebral column
Above the same number of vertebrae
61
In the lumbosacral level where do spinal nerves exit the vertebral column
Below the same number vertebrae
62
What is the neuromuscular junction
The synapse between lower motor neurons and skeletal muscle fibers
63
What is the neurotransmitter released in the neuromuscular junction
ACH
64
In the neuromuscular junction what are the receptors on the muscle
Nicotinic
65
In the neuromuscular junction what are the ion channels
Sodium and potassium
66
In the neuromuscular junction what is the effect on the muscle
Depolarizes and produces a muscle contraction
67
What happens in normal conditions in the neuromuscular junction
Enough neurotransmitter is released to produce an effect
68
What is a miniature endplate potential
Where small amount of ACH creates a small depolarization not enough to contract a muscle
69
What is the function of a miniature endplate potential
Signal to muscle that there is a functional nerve which maintains the integrity of muscle fibers
70
If there are no miniature endplate potentials what do you see
The nerve is injured
| muscle atrophy
71
What is Myasthenia gravis
And auto immune disease that damages ACH receptors at the neuromuscular junction
72
What happens in myasthenia gravis
Repeated use of the muscle leads to increased weakness
73
What are the first muscles affected in myasthenia gravis
Eye muscles
74
What does botulism interfere with
the release of ACH from the motor axon
75
What does botulism produce
Acute progressive weakness with loss of stretch reflexes
| sensation remains intact
76
What does botulism do to vesicles
Binds to vesicles and permanently inactivate them
| does not have permanent effects because it makes new synapses
77
What are the antibodies to myasthenia gravis
NMJ ACH receptor
78
What muscles are more affected in myasthenia gravis
Proximal limb muscles
diaphragm
Eye movement muscles
79
When does myasthenia gravis tend to affect men
In the sixth and seventh decades
80
When does myasthenia gravis tend to affect women
In the second and third decades
81
What makes the toxin in botulinum toxin
Clostridium botulinum
82
What are signs and symptoms of botulinum toxin
Acute weakness
| little sensory loss
83
What is botulinum toxin used for in clinical purposes
Spasticity and dystonia
84
What are myopathies
Injury to the muscle
| disorder intrinsic to muscle
85
What muscles are more weak in myopathies
Proximal than distal weakness
86
What do you see in myopathies
Paresis
87
What are myopathies not due to
Dysfunction of the nervous system
| There are no sensory deficits and no autonomic dysfunction
88
How does movement optimize the health of nerves
By promoting blood flow through the nerves and the flow of axoplasm through the axons
causes axoplasm to thin and flow more easily
89
What is neuropathy
Disorders of peripheral nerves
90
Signs of peripheral nerve damage include changes in
Sensory autonomic and motor
91
In dysfunction of peripheral nerves what do you see in sensory changes
```
Decreased or lost sensation
hyperalgesia
dysesthesia
paresthesia
allodynia
```
92
What is hyperalgesia
Increased sensitivity to pain
93
What is dysesthesia
Abnormal sensations that are painful
94
What is paresthesia
Abnormal sensations that are not painful such as tingling
95
What is allodynia
Sensations that are not painful are perceived as painful
96
What do signs depend on in autonomic changes of dysfunction of peripheral nerves
The pattern of axonal dysfunction
97
Where are signs of single nerve dysfunction of autonomic changes observed
They're observed only if the nerve is completely severed
| see problems where the nerve goes to
98
What are signs of many nerves of autonomic changes in peripheral nerve dysfunction
Difficulty regulating blood pressure heart rate sweating Bowel and bladder functions and impotence
99
What are signs of peripheral nerve damage in motor changes
Paresis or paralysis
100
If there are motor changes in peripheral nerve damage what does the EMG recording show
no activity for +/-1 weeks after injury
101
What happens in motor changes of peripheral nerve damage
Muscle atrophy progresses rapidly
102
After week period In motor changes of peripheral nerve damage what happens
Muscle fibers begin to develop a generalized sensitivity to ACH along the muscle membrane membrane
fibrillation ensues
103
What does fibrillation tell you
| what is it not
The nerve is not functioning and loses connection between the nerve and the muscle
it is not a diagnostic of a specific lesion
104
What do you see in tone and reflexes in motor changes
Decreased
105
What kind of atrophy is there in motor changes
Rapid and severe
106
What are tropic changes
Changes that occur in the denervated tissues
| changes in blood supply sensation and lack of movement
107
What do you see in changes that occur in denervated tissues
Skin becomes shiny and thin
nails become brittle
subcutaneous tissues thicken
108
What do you see in changes in blood supply, sensation and lack of movement in tropic changes
Ulceration of cutaneous and subcutaneous tissues
Poor healing of wounds
increased risk of infection
neurogenic joint damage
109
What is neurogenic joint damage
Damage to joints secondary to loss of muscle function
110
What can peripheral neuropathy involve
Single nerve several nerves or many nerves
111
What is mononeuropathy
Involves a single nerve and is considered a focal dysfunction
112
What is multiple mononeuropathy
Involves several nerves and is multifocal
113
What is polyneuropathy
Involves many nerves and is a generalized disorder that typically has a distal and symmetrical presentation
114
In mononeuropathy ,depending on the severity of the damage, what three categories are injuries classified in
Traumatic myelinopathy- neurapraxia
traumatic axonopathy- axinotmesis
Severance- neurotmesis
115
What is traumatic myelinopathy-neurapraxia
Damage to the Myelin sheath
| everything else is intact
116
What is traumatic axonopathy-axinotmesis
Damage to axons
| everything else is intact
117
What is severance- neurotmesis
Damage to the nerve
| damage everything were cut occurred
118
What do peripheral myelinopathies interfere with
The function of large diameter axons
119
What causes Traumatic myelinopathy
Focal compression of a peripheral nerve
| E.g. Brace too tight
120
What causes focal compression
Repeated mechanical stimuli
121
How many levels are there in the cervical spinal cord
Eight
122
What does traumatic axonopathy do
Disrupts axons and Wallerian degeneration
123
Where does Traumatic axonopathy
Distal to the lesion
124
What size of axons do axonopathies affect
All sizes especially large diameter
125
What are significantly reduced or absent in traumatic axonopathy
Reflexes
Somatosensation
motor function
126
In traumatic axonopathy, regenerating axons are able to re-innervate appropriate targets how
Because Myelin and connective tissue's remain intact
127
What is severance
It occurs when nerves are physically divided by excessive stretching or a laceration
128
What happens in severance
immediate loss of sensation and or muscle paralysis in the area supplied
129
In severance if proximal and distal nerve stumps are apposed and scarring does not interfere what happens
Some sprouts enter the distal stump and Are guided to their target tissue in the periphery
130
What can cause multiple mononeuropathy
Vasculitis
131
Vasculitis is suspected what should you do
An urgent referral should be made for an electrodiagnostic evaluation
132
What happens to nerves in multiple mononeuropathy
Individual nerves are affected producing a random asymmetrical presentation of signs
133
What are signs of polyneuropathy
Symmetrical involvement of sensory motor and autonomic fibers often progressing from distal to proximal
134
Where do symptoms begin in polyneuropathy
In the feet and then appear in the hands and areas of the body supplied by the longest axons
135
What are Polyneuropathies not a result of
Ischemia or trauma
136
What are the most common causes of polyneuropathy
Diabetes nutritional deficiencies secondary to alcoholism and autoimmune diseases
137
What are other causes of polyneuropathy
```
Toxic
metabolic
autoimmune
therapeutic drugs
industrial and agricultural toxins
nutritional disorders
```
138
What do you see in polyneuropathy for a pattern
Stocking glove pattern
139
What is an autoimmune disease often affected by polyneuropathy
Guillain-Barré
140
Polyneuropathy Guillain-Barré is characterized by
More severe effects on the motor system then the sensory system
141
In Guillain barre onset is
Rapid with progressive paralysis
142
In polyneuropathy the most common inherited form is
Charcot Marie tooth disease
143
What happens in Charcot Marie tooth disease
Causes precess of muscles distal to the knee with resulting footdrop steppage gait frequent tripping and muscle atrophy and progression muscle atrophy and precess affects the hands
144
When does charcot Marie tooth disease typically occur
Adolescence or young adults but varies with the type
145
What are causes of diabetic polyneuropathy
Vascular changes
| metabolic changes
146
What is the pattern in diabetic polyneuropathy
Usually distal symmetrical polyneuropathy
147
What happens in diabetic polyneuropathy
There's injury to axons and myelin sheath
148
What is affected predominately in diabetic polyneuropathy
Sensory neurons of all sizes
149
What effects do you see in diabetic polyneuropathy
Decreased sensation
pain
paresthesia
dysesthesias
150
In diabetic polyneuropathy loss of pain sensation often leads to what
Foot ulcers and damage joints in the foot
151
What occurs later in diabetic polyneuropathy
Muscle atrophy and weakness also predominantly distal
152
What are half of nondramatic foot amputations related to
Diabetes
153
What might you also see in diabetic polyneuropathy
Autonomic dysfunction
154
What are potential long-term adverse effects of neuropathy
Incomplete or aberrant innervation
| complex regional pain syndrome
155
What is treatment for peripheral neuropathy
Should be taught to visually inspect the involved areas daily to monitor for wounds and for reddening of the skin that persists more than a few minutes
proper footcare should be taught if feet are involved example socks without seems, not going barefoot, make sure shoes fit properly
Interventions for edema, contractures prevention, endurance exercises
156
What do interventions for edema include
Elevation of the limb compression bandaging electrical stimulation
157
How can contractures be prevented
Prolonged stretching or by daily activities
158
What have endurance exercise after peripheral nerve crush injury shown
They enhance sensory and motor recovery
