Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

MedPsych Exam 3 > Peripheral Nerve Injury > Flashcards

Peripheral Nerve Injury Flashcards

(48 cards)

Start Studying
1
Q

what are traumas that cause injury to peripheral nerves?

A

Penetrating injury
Crush
Traction
Ischemia

Thermal
Percussion
Vibration

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

what causes laceration of PN’s?

A

glass, knife, fan, saw, metal or long bone fractures = 30% of serious nerve injuries

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

what PN is most commonly injured? 2nd most common?

A

ulner n.

median n.

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

what are the types of crush injuries?

A
  1. acute: arm impingement, immediate attention.

2. overuse crush: caused by overuse. double crush if 2 injured

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

what is a stretch injury?

A

Injury to the nerves of the neck and shoulder under high velocity that cause burning or stinging feeling
aka brachial plex injury

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

what can PNI cause?

A

Injury may result in demyelination or axonal degeneration,

Both can disrupt sensory and/or motor function

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

when does recovery occur in PNI?

A

When re-myelination with axonal regeneration occurs

AND re-innervation of sensory and motor receptors

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

what systems do PNI’s effect?

A

Motor
Sensory
Reflex
Autonomic

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

what is the anatomy of a PN (outer-inner)

A

Epineurial sheath (outside covering)
Epineurium (ground substance)
Bundle: perineurium
Fascicle: endoneurium (axon inside)

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

what are Seddons 3 levels of PNI?

A
  1. neuropraxia
  2. axonotmesis
  3. neurotmesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is neuropraxia?

A

least sever PNI
axonal continuity preserved, recovery rapid
only at site of injury

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

what is axonotmesis?

A

axons disrupted
recovery depends on distance from injury to end organ
spontaneous recovery

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

what is neurotmesis?

A

most sever
complete anatomical disruption
no spontaneous healing

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

what are Sunderlands 5 levels of PNI?

A

First Degree = Neuropraxia
Second Degree = Axonotemesis
Third Degree = Endoneurial covering severed
Fourth Degree = Perineurium disrupted
Fifth Degree = Complete disruption of nerve trunk, little hope of spontaneous recovery

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

where is the emphasis placed in sunderlands 5 levels of PNI?

A

fascicle structure of PN

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

what do response from sensory end organs depend on?

A

Atrophy
Degeneration
disappearance of PN
time spent detached (shorter recovery window)

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

what are the 3 most common sensory end organs?

A

Meissner Corpuscle
Merkel Cell
Pacinian Corpuscle

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

what are the implications of injured motor end organs?

A

Muscle atrophies, ceases to function
Progressive shrinkage of muscle fibers
longer window for recovery

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

what are internal forces of compression?

A

Tumors, fractures, callus

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

what are external forces of compression?

Study These Flashcards
A

Tourniquet, crutches

21
Q

what are sensory consequences of nerve injury?

Study These Flashcards
A

Joints may become traumatized
Pt may injure themselves
Loss of hand function (dont know how much things weigh)

22
Q

what are motor loss consequences of PNI?

Study These Flashcards
A

Venous & lymphatic
stasis
Fibrosis
Muscle Atrophy

23
Q

what are the vasomotor consequences of PNI?

Study These Flashcards
A

Nutrition of bone & joints impaired
Sweat response abnormality
Sympathetic vasomotor instability

24
Q

what are the timing considerations of PNI surgery?

Study These Flashcards
A

12-18 months irreversible muscle atrophy has occurred, surgery not helpful

18-24 months edoneurial tube viable, if it doesn’t receive regenerating axon within time frame, tube will degenerate

25
what are other surgical considerations for PNI?
Condition of pt | Status of associated injuries
26
what is end to end repair?
sewing fascicles and outside of nerve together
27
what are surgical problems with end to end repair?
degeneration wrong receptor no connection misdirection
28
what is a nerve graft?
used when there is wide gap | sew smaller nerves from different part of body to est. alignment (sural)
29
what is conduit repair?
man made structure stitched around nerves to allow regrowth
30
what defines regeneration?
when nerve allows impulse
31
what are mechanical factors that influence regeneration?
Scar tissue | Alignment of fascicles
32
what delay factor affects regeneration?
Time related changes in distal nerve | segment & target end organs
33
how does age affect regeneration?
pts over 18 are harder to regenerate
34
how does level of injury affect regeneration?
More proximal = worse prognosis | inch of regeneration a month
35
what is the reparation process called?
axonal regeneration
36
what is needed for successful PN regeneration?
Central neuron must survive Axon growth in supportive environment Axon must make appropriate distal contact CNS must integrate peripheral nerve signal appropriately
37
what are the implications for tendon (muscle) transfer?
lose grade of strength but regain fxing therapists must train muscles to do different actions
38
what nerve can do transfers to any muscle?
MC n.
39
what does injury to median nerve cause?
``` “ape hand” Deficits – Inability to oppose thumb – Decrease in web space – Inability to perform 3 jaw chuck pinch ```
40
what is there a decrease in after median nerve injury?
``` power grasp FDS (high lesion) FDP index & long fingers pronation ```
41
what does injury to the radial nerve cause?
``` Wrist drop – Inability to extend fingers at MCP Deficits – Loss of finger, wrist, thumb extension – Decrease in forceful opposition ```
42
what are signs of ulnar nerve injury?
``` Froment’s = FPL substitutes for adductor Wartenburg = Inability to Adduct small finger ```
43
what does injury to the ulnar nerve cause?
``` Deformity – claw hand, hand of benediction Deficits – Loss of IV & V extension – Loss of key pinch – Weak hook and power grasps Sensory Loss – Ulnar border of hand, small finger easily injured ```
44
how do you test for positive Froments sign?
place piece of paper in hand between thumb. clawing with FPL instead of adducting thumb
45
what are the tendon/muscle transfers for the radial nerve?
Pronator Teres M. for wrist extension (ECRL & B) FCU or FDS for finger extension (EDC) PL or FDS for thumb extension (EPL)
46
what is the fx of the median n?
1. flexion of index & middle fingers using FDP tenodesis, ECU 2. thumb flexion using brachioradialis 3. thumb opposition Using EIP, FDS #3 & 4, ECRL, Abductor DM, EDM, ECU, PL
47
what is the role of OT in PNI?
``` Assist with evaluation/diagnosis – MMT – Sensibility Splinting Patient Education Physical Rehab – Muscle re-education – Sensory re-education ```
48
how do OTs teach sensory re-education?
once sensory return begins use extra stimulations on the outside to re learn input

MedPsych Exam 3 (7 decks)

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