Peripheral nerves and muscles

Question 0

PNS injuries typically cause what effect?

Answer 0

Injuries causing flacid and hyptotonia

Question 1

Typically CNS injuries cause what effect?

Answer 1

spasticity and overactivity

Question 2

True or false; the neuron is the parenchyma of the PNS

Answer 2

true

Question 3

What is axonal neuropathology

Answer 3

direct injury to axon, degeneration of peripheral segment

Question 4

Repair from axonal neuropathy involves what?

Answer 4

axonal regrowth and remyelination

Question 5

True or false when an axon repairs following axonal neuropathy there is a decrease in amplitude

Answer 5

true

Question 6

Demyelinating neuropathy causes damage to what?

Answer 6

Schwann cell or myelin (spares axon)

Question 7

True or false; demyelinating neuropathy causes damage uniformly along total nerve

Answer 7

false

Question 8

What is mononeuropathy and what is a common example?

Answer 8

single nerve effected

Entrapment: carpal tunnel syndrome

Question 9

Is mononeuropathy asymmetric?

Answer 9

yes

Question 10

Diffuse/symmetric axonal loss best describes what?

Answer 10

polyneuropathy

Question 11

“stocking and glove” appearance commonly appears with what pathology?

Answer 11

polyneuropathy

Question 12

What is polyneuritis multiplex?

Answer 12

damage randomly affecting portions of individual nerves

Question 13

True or false; polyneuritis multiplex is a autoimmune disorder

Answer 13

true

Question 14

A common acute motor neuron demyelination causing ascending paralysis

Answer 14

Guillain-Barre syndrome (GBS)

Question 15

True or false; there appears to be a autoimmune function with Guillain-Barre syndrome (GBS) - with macrophages near nerve roots

Answer 15

true

Question 16

What is relapsing or chronic Guillain-Barre syndrome (GBS)

Answer 16

Chronic inflammatory demyelinating polyneuropathy (CIDP)

Question 17

A 50 year old male presents with ataxia (poorly coordinated movements) and onion-skin Schwann cells - what is the patient most likely suffering from

Answer 17

Chronic inflammatory demyelinating polyneuropathy (CIDP)

Question 18

What is the #1 cause of peripheral neuropathy

Answer 18

Diabetic peripheral neuropathy (50% diabetes myletis)

Question 19

True or false; environmental toxins typically damaged very short neurons

Answer 19

false; typically effect longest neurons

Question 20

True or false; 1/3 of all vasculitis patients have peripheral neuropathy

Answer 20

true

Question 21

PMP22 gene mutations can typically lead to what?

Answer 21

peripheral neuropathy (Charcot-Marie-tooth disease)

Question 22

What is Myasthenia gravis?

Answer 22

Auto-immune disorder degrading post-synaptic ACh receptors

Question 23

What symptoms are associated with myasthenia gravis?

Answer 23

Diplopia (double vision) and ptosis (drooping eyelid)

Question 24

True or false; Myasthenia gravis is commonly associated with thymic lesions

Answer 24

true (60% hyperplasia - thymoma 20%)

Question 25

True or false; symptoms with myasthenia gravis typically get worse as the day goes on

Answer 25

true

Question 26

Is myasthenia gravis more common in one sex?

Answer 26

yes - females

Question 27

What is Lambert-Eaton syndrome?

Answer 27

Autoimmune disorder - autoantibodies inhibit pre-synaptic Ca++ channels - decreasing ACh release

Question 28

True or false; a thymectomy can sometimes help patients with Myasthenia gravis

Answer 28

true

Question 29

Lambert-Eaton syndrome and Myasthenia gravis are both autoimmune disorders effecting ACh receptors - which has a worse prognosis

Answer 29

Lambert-Eaton syndrome - Myasthenia gravis has a 95% 5-year survival rate

Question 30

True or false; a thymectomy can greatly help a patient with Lambert-Eaton syndrome

Answer 30

false; it can help those with Myasthenia gravis though

Question 31

What is the difference between myasthenia gravis and lambert-eaton syndrome

Answer 31

Myasthenia gravis is autoimmune disease effecting post-synaptic ACh receptors Lambert-Eaton- autoimmune disease effecting pre-synaptic ACh receptors

Question 32

What does a Tetanus infection cause in human body

Answer 32

Increased ACh release

Question 33

What does a botulism infection cause in human body

Answer 33

decreased ACh release

Question 34

True or false; Botulism causes ascending paralysis

Answer 34

false; it causes descending paralysis (eyes-throat-respiration) Guillian-Barre syndrome causes ascending paralysis

Question 35

What kind of fibers are muscle fiber type 1? What about type 2?

Answer 35

Type 1: slow twitch, dark, aerobic, fat metabolism | Type 2: fast twitch, white, anaerobic, glycogen metabolism

Question 36

Grouped atrophy causing fewer and larger motor units is characteristic of what?

Answer 36

neuropathic changes

Question 37

Disuse atrophy primarily effects what kind muscle tissue?

Answer 37

Primarily type 2 fibers (following localized fracture - or generalized disuse from quadriplegia)

Question 38

Glucocorticoid atrophy primarily effects what kind of muscle tissue? How does this kind of atrophy typically occur?

Answer 38

Primarily effects type 2 fibers Typically occurs because of exogenous reasons (mis-use of corticosteriods - steroids used to inhibit inflammation) Can also occur by endogenous reasons like Cushing disease

Question 39

True or false; muscular dystrophy is typically congenital?

Answer 39

false; it is rarely congenital - typically occurs after ~5 years of age

Question 40

What is muscular dystrophy?

Answer 40

An inherited, progressive disorder - MC due to dystrophinopathies (not producing dystrophin)

Question 41

What is dystrophin? What are the two common disorders dealing with it?

Answer 41

Dystrophin is one of the longest genes in human genome; codes for protein vital in cytoskeleton Duchenne Muscular dystrophy and Becker muscular dystrophy

Question 42

What is the difference between Duchenne muscular dystrophy and Becker?

Answer 42

Duchenne is more severe - dystrophin gene completely absent - fatal by early adulthood Becker just abnormal dystrophin - possible normal lifespan

Question 43

What are some keynote symptoms to muscular dystrophy

Answer 43

Clumsiness, "can't keep up", pseudohypertrophy of calf muscles and "Gower sign" (using hands to push on legs to stand)

Question 44

What is polymyositis?

Answer 44

Autoimmune disorder (T cells attack endomysium) causes dysphagia (difficulty swallowing), proximal muscle weakness (45-60 yrs old)

Question 45

True or false; polymyositis, Dermatomyositis, and Inclusion body myositis are all examples of inflammatory myopathies

Answer 45

true

Question 46

What is the MC inflammatory myopathy in elderly

Answer 46

Inclusion body myositis (tau proteins in cytoplasm, progressive weakness, dysphagia)

Question 47

What is the MC inflammatory myopathy in children

Answer 47

Dermatomytositis; autoimmune, muscle & skin inflammation, proximal muscle weakness

Question 48

True or false; thyrotoxic myopathy, ethanol myopathy, and drug myopathy are all examples of toxic myopathies

Answer 48

true

Question 49

Overproduction of thyroxine, goiter or Graves disease, acute or chronic best describes what?

Answer 49

Thyrotoxic myopathy

Question 50

True or false; peripheral nerve sheath tumors are MC in adults

Answer 50

true

Question 51

True or false; schwannomas are commonly malignant

Answer 51

false; they are almost always benign (1% malignant)

Question 52

Schwannomas are benign peripheral nerve sheath tumors, they are MC involved with which C.N.?

Answer 52

VIII (vestibular schwannoma)

Question 53

What is the difference between Neurofibromatosis 1 & 2

Answer 53

1 - causes neurofibromas all over body (very pronounced) 2 - Bilateral vestibular schwannomas (vision and hearing problems) Both are autosomal dominant

Question 54

What is a neurofibroma

Answer 54

benign nerve sheath tumor

Question 55

True or false; 50% of all cases of malignant peripheral nerve sheath tumors arise in neurofibromatosis type 1 patients

Answer 55

true