Diseases of PNS & Skeletal Muscles

Question 1

2 Main Components of PNS

Answer 1

Axons

Myelin Sheaths

Question 2

Function Carried out by motor unit

Answer 2

Somatic Motor Function

Question 3

Somatic Motor Function consists of

Answer 3

Lower Motor Neuron - Located at Ant Horn
Axon
NMJ]
Myofibers

Question 4

Somatic Sensory function

Contain specialized structures that serve to register specific sensory modalities

Answer 4

Distal nerve endings

Question 5

How Fast:

Unmyelinated fibers mediate autonomic function as well as pain and temp sensation

Answer 5

Slowest Conduction

Question 6

How Fast:
Large diameter axons with thick myelin sheaths
transmit light touch and motor signals

Answer 6

Fast Conduction:

Question 7

Myelinated segment

Answer 7

Internode

Question 8

Unmyelinated Gaps

Answer 8

Nodes of Ranvier

Question 9

Intracellular protein that has role in myelin corporation

Answer 9

Myelin basic protein

Question 10

Dysfunction of Schwann cell

Answer 10

Guillain Barre Syndrome

Question 11

Damage to the myelin sheath

Answer 11

Hereditary motor and sensory neuropathy

Question 12

Disintegrating myelin is engulfed initially by

Answer 12

Schwann Cells

Question 13

Disintegrating myelin is engulfed Later by

Answer 13

Macrophages

Question 14

Stimulus for remyelination

Answer 14

Denuded axon

Question 15

Primary target of the damage in peripheral neurophathies

Answer 15

Axons

Question 16

Prototypcal pattern of injury when cutting a peripheral nerve the portions of axons that are distal to the point of transections are disconnected from the central neuron and degenerate

Answer 16

Wallerian Degeneration

Question 17

Electrophysiologic hallmark of axonal neuropathies

Answer 17

Reduction in signal strength owing to the dropout of axon from affected peripheral nerves

Question 18

Pattern of Pheripheral nerve damage where Type I and Type II myofibers are arranged in checker board distribution and the internodes along the motor axons are uniform in thickness and lenght

Answer 18

Normal Motor Units

Question 19

Pattern of Pheripheral nerve damage where result in degeneration of the distal axon and its associated myelin sheath with atrophy of denervated myofibers

Answer 19

Acute Axonal Injury

Question 20

Pattern of Pheripheral nerve damage where in acute demyelinating disease produces random segmental degeneration of individual myelin internodes, while sparing the axons

Answer 20

Acute Axonal Injury

Question 21

Pattern of Pheripheral nerve damage where it allows reinnervation of myofibers, the regenerated axon is myelinated by proliferating schwann cells but the new internodes are shorter and the myelin sheaths are thinner thatn the origineal ones

Answer 21

Regeneration of axons after Injury

Question 22

Pattern of Pheripheral nerve damage where remission of demyelinating disease allows remyelination to take place, but new internodes are also shorter and thinner myelin sheaths than flanking normal undamaged internodes

Answer 22

Regeneration of Axons after injury

Question 23

Generalized abnormality of axons affecting the neuron cell body

Answer 23

Neuronopathy

Question 24

Generalized abnormality of axons affecting the axon

Answer 24

Axonopathy

Question 25

Electrophysiologic hallmark of demyelinating neuropathies

Answer 25

Slowed nerve conduction velocity, reflective loss of myelin

Question 26

Common causes of mononeuropathies

Answer 26

Trauma, Entrapment and infections

Question 27

Disease process that damages several nerves in haphazard fashion

Answer 27

Mononeuritis multiplex

Question 28

An affected patiend might have a right wrist drop from involvement of the right radial nerve and left foot drip from peroneal nerve damage. Vasculitis is a common cause of this injury

Answer 28

Mononeuritis multiplex

Question 29

affect nerve roots as well as peripheal nerves, leading to diffuse symmetric symptoms in proximal and istal parts of the body

Answer 29

Polyradiculoneuropathies

Question 30

Diseases that are infectious polyneuropathies

Answer 30

Leprosy, Diptheria, Varicella xoster virus

Question 31

Characterized clinically by weakness: distal to proximal (Ascending Paralysis)

Answer 31

Guillian Barre Syndrome

Question 32

Inflammation of peripheral nerves, manifested as perivenular and endoneural infiltrationby lymphocytes macrophages and plasma cell

Answer 32

Guillian-Barre Syndrome

Question 33

inflammation and demyelination of spinal nerve roots and Peripheral Nerves

Answer 33

Guillian Barre Syndrome