Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

(OMS2) NMSP Exam 2 > [PATH] PNS and Skeletal Muscle [Martin] > Flashcards

[PATH] PNS and Skeletal Muscle [Martin] Flashcards

1
Q

Define:

Epineurium

A

Encloses entire nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define:

Perineurium

A

Multilayered, concentric connective tissue sheath that encloses each fascicle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define:

Endoneurium

A

Surrounds individual nerve fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

With neuromuscular dz, what is the primary symtpom?

A

Weakness;

due to disorder of motor unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 2 main responses of peripheral nerve injury?

A

Segmental demeylination

Axonal degeneration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Segmental demeylination occurs with?

A

Schwann cell and loss of myelin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Axonal degeneration occurs with?

A

Neuron and axon failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the LEFT vs RIGHT image showing?

A

LEFT = Segmental demyelination

RIGHT = Axonal degeneration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two basic pathologic processes that occur in the muscle?

A

Denervation atrophy

Myopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When does segmental demyelination occur?

A

When dysfunction of SCHWANN CELLS occurs and damage to the myelin sheath occurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the CLASSIC schwann cell disease?

A

Guillian Barre

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Does segmental demyelination affect all schwann cells?

A

NO!

Only certain SEGMENTS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a length characteristic of a newly myelinated internode?

(This is following segmental demyelination)

A

Shorter than normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a histologic characteristic of newly meylinated internodes following segmental demyelination?

A

Onion bulbs: concentric layers

of schwann cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a traumatic neuroma?

A

Following a trauma;

A failure of the outgrowing axons to find their distal target, can produce a “pseudotumor”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are myelin ovoids?

A

Schwann cells catabolize myelin and later engulf axon fragments which produces small oval compartments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a hallmark feature of axonal degeneration?

A

Denervation atrophy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do the atrophic fibers following axonal degeneration look like?

A

Triangular shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What determines the fiber type that will be regenerated?

A

The motor neuron determines the fiber type

*All muscle fibers of a single unit witll become the same type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Where is the normal nuclei distribution in a motor unit?

A

PERIPHERAL nuclei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where will nuclei be in a motor unit undergoing regeneration?

A

CENTER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What will be the pattern of reinnervation muscle fibers?

A

Uniform;

*it is NOT like the normal checkerboard pattern seen in healthy motor units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Quick review of type1 vs type2 muscle fibers

General overview of Type 1?

A

Sustained force

Weiht bearing

Slow-twitch

Red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Quick review of type1 vs type2 muscle fibers

General overview of Type 2?

A

Sudden movements

Fast-twitch

White

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
When do **type 2 fibers** typically undergo atrophy?
Inactivity/disuse Neurodegenerative disease Glucocorticoid therapy
26
Segmental necrosis: When there is a loss of muscle fiber, it can lead to?
Deposition of collagen and fat
27
What stain do you use to identify regeneration of muscle fibers?
Trichrome stain \*Cytoplasm is laden with RNA
28
What is a histologic feature of **hypertrophy?**
Muscle fiber splitting: Large fibgers may divide longitudinally
29
What is the common description of pain in patients with **peripheral neuropathies?**
Tingling, stabbing, burning or "pins and needles"
30
What is the typical distrubution of a **polyneuropathy?**
Stocking and glove distribution
31
Mononeuritis multiplex is commonly associated with?
Vasculitis (Polyarteritis nodosum = PAM)
32
How are the nerves damaged in **mononeuritis multiplex?**
Haphazard fashion
33
Bell's palsy is related to which CN?
CN VII
34
Signs of **bells palsy?**
One sided facial droop within 48-72 hours of initial symptoms
35
What is a **neurogenic bladder?**
A number of urinary conditions in people who **lack bladder control** due to a **brain, spinal cord** or **nerve problem**
36
What are some associated disease processes associated with **neurogenic bladder?**
Nerve damage Infection Spina bifida
37
Guillain-Barre What is it? How does it travel?
Acute inflammatory demyelinating polyneuropathy Weakness begins in distal limbs, but rapidly advances to proximal muscles "**ascending paralysis"** -DTRs disappear
38
Guillain-Barre What is the biggest organism that can cause?
Campylobacter jejuni
39
Guillain-Barre What type of antibodies are formed?
Anti-myelin antibodies
40
Guillain-Barre Whta will the CSF look like?
Increased protein That's it!!! (The inflammatory cells remain confined to the roots, therefore, very little or no CSF infiltration will be seen)
41
**Guillain-Barre** Treatment?
Plasmapheresis; IVIg
42
What are the three major **infectious polyneuropathies?**
Leprosy (Hansen disease) Diptheria Varicella zoster virus
43
What is the path behind **leprosy?**
Schwann cells invaded by **mycobacterium leprae**
44
What kind of demyelination occurs in **leprosy?**
Loss of BOTH myelinated and unmyelinated axons
45
Leprosy primarily involves which parts of the body?
Cool extremities (lower temp favors mycobacterium growth)
46
What is one mechanism that contributes to **leprosy** injury?
Involvement of pain fibers that leads to loss of **sensation**
47
What is the knee-jerk (+) stain pattern you should associate with **leprosy?**
AFB
48
What is the path behind **diptheria?**
Diptheria **exotoxin** affects peripheral nerves and begins with **paresthesias** and **weakness**
49
What is the most common **viral infection of PNS?**
Varicella-zoster virus
50
Where does **varicella zoster** virus typically attack first?
Sensory ganglia of spinal cord and brainstem
51
What does **reactivation** of varicella zoster virus lead to?
Shingles
52
What is the most common cause of peripheral neruopathy?
Diabetes
53
What fibers are typically affected in **diabetic neuropathy?**
Small myelinated fibers Unmyelinated fibers
54
What nerve is involved in **carpel tunnel?**
Median n.
55
What nerve is involved in **saturday night palsy?**
Radial n.
56
What is the most common **inherited peripheral neuropathy?**
Charcot-Marie-Tooth (CMT)
57
What is the most common disease of **neuromuscular junction?**
Myasthenia Gravis
58
What is the path of **myasthenia gravis?**
Immune mediated loss of acetylcholine receptors; \*Circulating **autoantibodies to AChR**
59
What is a strong association for **myasthenia gravis?**
Thymic abnormalities
60
What is the clincal description of a patient with **myasthenia gravis?**
Present with fluctuating general weakness that **worsens** with exertion and **over the course of the day** **Drooping eyelids**, weakness in extraocular muscles
61
What is the classic sign following examination that a patient has **myasthenia gravis?**
**Diminished responses** after repeated stimulation
62
What is the path of **lambert-eaton** myasthenic syndrome?
Antibodies block **acetylcholine release** by inhibiting **presynaptic Ca2+** channel
63
Lambert-eaton is a ________ process, mostly derivative of \_\_\_\_\_\_\_\_\_\_\_\_
Paraneoplastic Small cell carcinoma of the lung
64
What is the response in **lambert-eaton** syndrome that is the OPPOSITE of myasthenia gravis?
Repetitive stimulation **increases** muscle response
65
Fascicles are associated with a \_\_\_\_\_\_\_\_\_\_\_
Small pool of tissue stem cells = Satellite cells
66
What disease of skeletal muscle is associated with **perifascicular atrophy?**
Dermatomyositis
67
Dematomyositis Describe the distinctive skin rash
Iilac or heliotrope discoloration of the **eyelids** **Telangiectasias** (dilated capillary loops) in nail folds, eyelids and gums **Grotton lesions**
68
Dermatomyositis Symptoms?
Proximal muscles first Dysphagia Difficulty rising from chair, climbing stairs Cardiac involvement
69
Dermatomyositis Associated antibodies?
Anti-Mi2 Anti-Jo1
70
Dermatomyositis Histo?
Perifascicular atrophy
71
Inclusion body myositis Describe
Slowly progressive muscle weakness, Most severe in **quadriceps** and **distal upper extremities**
72
Inclusion body myositis Histo?
Rimmed vacuoles
73
What is the first line therapy for inflammatory myopathies?
Corticosteroids
74
What drug categories are related to **toxic myopathies?**
Statins Chloroquine & hydroxychloroquine
75
X-linked muscular dystrophy Which type is more common and more severe? Which type is less common and less severe?
More common, more severe = Duchenne (DMD) Less common, less severe = Becker (BMD)
76
What gene is affected in x-linked muscular dystrophy? What protein?
DMD gene:Xp21 Dystrophin
77
What does the production level of dystrophin say about the severity of the muscular dystrophy?
DMD = NO dystrophin produced BMD = Very little dystrophin made
78
What is **pseudohypertrophy?**
Enlargement of muscles of lower leg associated with weakness; increased **bulk** and **size** occurs initially; Later there is an increase in **fat and connective tissue**
79
What is **myotonic dystrophy?**
Sustained involuntary contraction of a group of muscles; can be elicited by **percussion on thenar eminence**
80
What are the symtpoms of **myotonic dystrophy?**
Skeletal muscle weakness Cataracts Endocrinopathy Cardiomyopathy "Stiffness", difficulty releasing grip
81
Inheritance pattern of **myotonic dystrophy?**
Autosomal dominant CTG trinucleotide repeat
82
What is the appearance of someone with **myotonic dystrophy?**
"Hatchet face"
83
What are the two general patterns of muscle dysfunction with **lipid/glycogen** metabolism?
1) Symtpoms with **exercise** or **fasting** 2) **Slowly progressive** muscle damage
84
What are common symptoms associated with **mitochondrial myopathies?**
Sxs: Weakness, increase in serum CK or rhabdomyolysis **Extraocular muscle** involvement
85
What is the histo appearance of **mitochondrial** myopathies?
Ragged red fibers
86
What are the symtpoms of **spinal muscular atrophy (SMA)?**
Generalized hypotonia "Floppy infant"
87
Malignant hyperthermia is a **channelopathy** with what mutation?
RYR1
88
What are the characteristics of **tuberous sclerosis?**
AD Hamartomas Renal angiomyolipomas Cardiac rhabdomyomas Shagreen patches, Ash-leaf patches
89
Characteristics of **neurofibromatosis type 1**
Common Neurofibromas of peripheral nerves **Optic nerve gliomas** **Lisch nodules** **Cafe au lait** spots
90
Characteristics of **neurofibromatosis type 2**
Less common Bilateral **swannomas (CNVIII)** Increased **meningiomas, ependymomas**
91
Schwannoma Sxs?
CN VIII tinnitus hearing loss
92
Schwannoma Gene?
NF2: loss of merlin
93
Neurofibroma description?
Bag of worms
94

(OMS2) NMSP Exam 2 (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions