Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neuromuscular PT 1 > PNS > Flashcards

PNS Flashcards

1
Q

PNS regions

A
  • peripheral nerves
  • cranial nerves (all but two)
  • autonmoic nervous system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is in the PNS

A
  • all structures distal to spinal Nerves
  • axons of sensory,motor, and autonomic neurons
  • specialized sensory endings
  • postganglionic autonimic neurons
  • cranial nerves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where does the peripheral nervous system start (where does spinal region stop)

A
  • where the spinal nerve bifurcates into ventral and dorsal rami
  • marks the transition from spinal to peripheral region
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Peripheral nerve structure: describe from axons to nerve

A
  • individual axons are surrounded by the endoneurum and myelin sheath
  • bundles of axons = fascicles and fascicles are surrouned by perineurium
  • epineurium is the outermost that surrounds the nerve
  • Mesoneurium surrounds the nerve trunk and that allows gliding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Myelin in the PNS

A
  • Surrounds 1 axon = myelinated (schwann cells)
  • or surrounds several axons = paritially myelinated or unmyelinated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Peripheral nerve blood supply

A
  • receive blood supply via arterial branches that enter the nerve trunk
  • supples groups of axons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where do peripheral nerves go?

A
  1. splanchnic –nerves that supply signals and info to and from the visceral organs and blood vessels
  2. Cutaneous—not purely sensory—they deliver efferent axons to sweat glands and arterioles
  3. Muscular branches not purely motor –they contain sensory axons from proprioceptive structures.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Nerve plexuses

what are they and the types

A
  • formed by junctions of anterior rami
  • cervical plexus
  • brachial plexus
  • lumbar plexus
  • sacral plexus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Cervical Plexus

A
  • arises from anterior rami of C1-C4
  • lies deep the SCM
  • phrenic nerve most important branch as it is only motor supply and sensory nerve for diaphragm
  • sympathetic innervation
  • cutaneous innervation for posterior scalp to clavicle, anterior neck muscles and diaphragm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Brachial plexus

A
  • Innervate the upper limb
  • sympathetic innervation
  • formed by anterior rami of C5-T1
  • emerges between the anterior and middle scelenes and then deep to clavicle into axilla
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Lumbar Plexus

A
  • L1-L4
  • innervates skin and muscles of anterior and medial thigh
  • cutaneous branch to medial leg and foot - saphenous nerve
  • sympathetic innervation
  • forms in the psoas major muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Sacral plexus

A
  • formed by anterior rami of S1-S4
  • innervates posterior thigh, most of leg and foot
  • parasympathetic and sympathetic
  • only one that has motor, sensory, parasympathetic and sympathetic innervation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Peripherl nerve damage: S&S

A
  • Sensory
  • autonmic
  • motor
  • Trophic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Sensory S&S of peripheral nerve damage

A
  • changes include decreased or loss of sensation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

S&S of peripheral nerve damage

Autonomic

A
  • Depends on pattern of dysfunction
  • if a single nerve is damaged, autonmic signs usually are observed only if the nerve is completely severed
  • signs may include lack of sweating, loss of sympathetic control of smooth muscle in arterial walls
  • this can contribute to edema in affected limb
  • if many neurons are involved, autonmic problems may include impotence, difficulty regulating blood pressure, heart rate, sweating and bowel and bladder functions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

S&S of peripheral nerve damage

Motor

A
  • paresis/weakening or paralysis
  • denervation determined by EMG
  • MM atrophy progresses rapidly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

S&S of peripheral nerve damage

Trophic changes

A
  • muscle atrophy
  • shiny skin
  • birttle nails
  • subcutaneous tissue thickens
  • tissue ulceration
  • poor healing of wounds and infection
  • neurogenic joint damage (coming from NS) due to blood supply changes
  • loss of sensation and lack of movement
18
Q

Classifications of neuropathies

A
  1. traumatic myelinopathy
  2. traumatic axonopathy
  3. traumatic severance
  4. multiple mononeuropathy
  5. polyneuropathy

neuropathy = disease or dysfunction of one or more peripheral nerves

19
Q

Traumatic myelinopathy

A
  • Focal compression of a peripheral nerve
  • caused by excessive pressure, stretch, vibration and/or friction
20
Q

Traumatic myelinopathy

what happens with a traumatic myelinopathy

as a result

A
  • Decreased axonal transport
  • decrease epineurial blood flow
  • decreased blood flow causes edema/swelling of epineurium and endoneurium
  • The edema restricts blood and axoplasmic flow (axon is intact but not working well)
  • Perineurium and epineurium thicken

ex: carpal tunnel syndrome

21
Q

Traumatic myelinopathy

what happens with perineurium and epineurium thickening

A
  • damages myelin
  • decreased nerve conduction velocity = impaired sensation and movement
  • ectopic folci develop due to altered gene activity in cell = neurpathic pain
22
Q

What does traumatic myelinopathy interfere with and what functions are intact and recovery

A
  • interferes with the function of large diameter axons producing motor, discriminitive touch, proprioceptive and phasic stretch reflex defecits and cause neuropathic pain
  • unless injury is unusually severe autonmic function is intact and axons are not damaged
  • recovery tends to be complete remyleination before rapdily irrversible damage occurs
23
Q

How movement is important especially with traumic myelinopathy

A
  • promotes blood flow: oxygenation of nerves and removal of wast
  • promotes axoplasmic flow: keeps axoplasm thin => improves transport
  • Axoplasm gets thicker without movement
  • Nerve glides can help
24
Q

How do nerves move

A
  • Nerves can fold and unfold

as a nerve is stretched:

  • viscoelastic tubes formed by endoneurium, perineurium and epineurium stretch
  • axons unfold
  • fascicles glide along each other
  • entire nerve stretches relative to other structures
  • if stretch continues tensile stress develops over the nervous tissue
  • nerve glides
25
Q

Traumatic axonopathy

A
  • the axon is damaged
  • myelin is intact
  • crush injury due to dislocation or fracture is often the cause
26
Q

What are signs and symptoms Traumatic axonopathy + recovery

A
  • reflexes, somatosensation and motor function are markedly reduced or absent
  • muscle atrophy occurs
  • recovery is generally good - axon regrowth typically proceeds at a rate of 1mm/day
  • wallerian degeneration distal to lesion
27
Q

What is wallerian degeneration in PNS

A
  • Day 1 axon becomes swollen and irregular
  • by day 3-4: axon is fragmented; debris digested by glial cells
  • 1 week: entire axon is destroyed; seperated in proximal and distal segments results in death of distal segment - cell body undergoes changes and dies
  • Changes in proximal segment: similar to those in distal segment but only extend as far as first node of ranvier
28
Q

Changes that occur in the cell body in response to injury

A
  • retrograde degeneration = chromotaolysis
  • may be related to loss of trophic factors
  • nucleus moves to one side of cell body
  • if axon regenerates and proper connections are restored, chromatolysis stops
  • if not cell trophies and dies
  • axon re-grows at rate of 1mm/day
29
Q

Chromatolysis

explain the process

A
  1. normal axon
  2. axon severed
  3. nucleus moves in cell body/severed axon sprouting occurs
  4. sprouts degenerate/axon regenerates
  5. chromatolysis ends and either reinnervates the target or is unable to regenerate and dies
30
Q

Traumatic severance

A
  • nerve completely disrupted; excessive stretch or laceration
  • immediate loss of sensation/paralysis
  • wallerian degeneration begins 3-5 days later
  • axons in proximal stumps will begin to sprout - sprounts may enter distal stumps and reach target
31
Q

Recovery from severance

traumatic severence

A
  • axons in proximal stumps will begin to sprout
  • sprouts may enter distal stump and reach target
  • stumps may be displaced or scar tissue may be in the way = neuroma
  • sprouts may reach inappropriate end organ
32
Q

Neuroma

A
  • if stumps are displaced or if scar tissue intervenes between stumps, sprouts may grow into this tangled mass of nerve fibers
33
Q

Sprouting

A
  • collateral sprouting = a denervated neuron attracks side sprouting from nearby undamaged axons
  • regerative sprouting - injured axon issues side sprouts to form new synpase with undamaged neurons
34
Q

Multiple mononeurpathy

A
  • individual nerves affected
  • random, asymmetric presentaton of signs
  • possible cause = vasculitis
  • may result in rupture/need for referral
35
Q

Polyneuropathy

A
  • symmetric involvement of sensory, motor, and autonomic fibers
  • often progressing from distal to proximal
  • stocking/glove distribution
  • degeneration of distal part of the long acons may occur because of inadequate axonal transport to keep the distal axons viable and because longer axons have more myelin
36
Q

Common causes of poly neuropathy

A
  • diabtetes
  • nutritional deficiences due to alcoholism
  • autoimmune disease
  • also develops with age
37
Q

What can happen with severe polyneuropathies

S&S

A
  • trophic changes
  • poor healing
  • ulceration
  • poor sensation and therefore protective sensation
  • most common = diabetic and Gullian Barre
38
Q

Diabetic polyneuropathy

A
  • axon and myelin damage
  • sensation is primarily affected
  • decreased ankle reflexes and later strength and joint damage
  • decreased balance
  • role of PT: strengthen, balance exercises, education etc
39
Q

Gullian barre

A
  • rapid onset, with progressive paralysis
  • greater motor effects verus sensory
  • distal to proximal sensory loss
  • early diagnosis key to preventing res. failure
40
Q

Charcot Marie Tooth disease

A
  • hereditay
  • muscle weakness distal to the knee
  • atrophy and weakness eventually effect the hands
  • sensation to heat, cold, and painful stimuli impaired
  • neuropathic pain is common
  • muscle weakness in foot drop, steppage gait, frequent tripping, muscle atrophy
  • charcot marie foot = pes cavus type position
41
Q

myopathy

A
  • specific to muscle
  • peripherl nerve specific to muscle
  • random muscle fibers degenerate leaving motor units with fewer muscle fibers
  • ex: muscular dystrophy
42
Q

Diagnositcs and clinical testing of the PNS

A
  • EMG or NCS/NCV
  • ankle jerk reflex
  • imparied vibration sense
  • imparied position sense of great toe
  • 2/3 signs correlate with electrodiagnostics

Neuromuscular PT 1 (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions