Elbow, Hand Peripheral Nerve Injury Flashcards
1
Q
What can a Nerve injury be due to?
A
- traction
- compression
- crush injruy
- fracture
- laceration
- entrapment in scar tissue healing
- surgery
2
Q
Peripheral Nerve Injury Signs and symptoms
A
- Sensory changes in peripheral nerve pattern (paresthesia/anesthesia)
- pain
- Motor loss and weakness
3
Q
- Paresthesia
- Anesthesia
A
- numbness/tingling/burning
- loss of sensation
4
Q
What is compartment syndrome
A
- volksmans ischemic contracture
- rapid increase in pressure from bleeding and swelling
- compression causes ischemia and damage to tissues
- can cause muscle necrosis or peripheral nerve injury
5
Q
How to determine Involved Nerve?
anatomy
A
- nerve course
- sensation altered (nerve pattern)
- muscles nerve innervates (weakness)
- site of nerve lesion
6
Q
How can the site of nerve lesion be used to determin the involvment of a peripheral nerve?
A
- adjacent structure involved (muscule/tendon, ligament, bone spur, fracutre, scar tissue, tumor)
- mechanism of injury: compression caused by poor posture, hypertrophy and muscule contraction, traction injury, laceration, crush, post op/entrapment
7
Q
What are the nerve injury classifications
A
- neuropraxia
- axonotmesis
- nerotmesis
8
Q
Nerve injury classifications:
neuropraxia
A
- ischemia due to pressure or traction
- decreased nerve conduction at the site (above/below are normal)
- focal demyelination
- minimal damage to nerve structure
- no muscule atrophy
- best prognosis - recover in 6 weeks
9
Q
Nerve injury classifications
axonotmesis
A
- compression or traction to nerve
- extend of damage is axon
- Ct is left intact
- wallerian degneration
- Muscule fiber atrophy - motor loss
- sensory loss
- nerve recovery - regenerates 1mm/ day or 1 inch per month
10
Q
Wallerian degeneration
A
- degeneration that goes distally from the point of damage
11
Q
- neurotmesis
A
- complete disruption of both axon and CT
- Wallerian degneration
- muscule fiber trophy/motor loss
- sensory loss
- requires surgical repair (WORST prognosis)
- healing = scar tissue can entrap the nerve
12
Q
Axillary nerve:
- course
- MOI
- Motor
- Senory
- functional loss
A
Course:
- off posterior cord, posterior through axilla
- quadrangular space
- behind surgical neck of humerus
MOI:
- dislocation of shoulder
- fracture - surgical neck of humerus
Motor:
- deltoid, teres minor
Sensory:
- deltoid region
Functional loss:
- weak shoulder abduction and ER (no affect at elbow or hand)
13
Q
Radial nerve course
A
- Posterior cord C5-T1
- triangular interval
- posterior humerus
- radial grooe
- anterior later epicondyle
- supinator split (posterior interosseus n.)
- Anterior lateral in forearm
14
Q
Radial n. motor
A
- tricpes
- anconeus
- supinator
- brachioradalis
- Wrist, finger and thumb extenors
15
Q
Radial nerve Sensory
A
- posterior cutaneous n. = arm and forearm
- Superifical radial n. = dorsal radial hand
16
Q
Radial N. Entrapment
midshaft of humerus facture
A
- lose tricpes, all motor below
- drop wrist
- all sensory lost
17
Q
Radial N. entrapment
saturday night palsy
A
- Spared = triceps
- lose all motor below = brachioradialis, supinator, wrist finger and thumb extenors
- drop wrist
- sensation: lose everything below level of injury
18
Q
Radial nerve entrapment
- Radial tunnel
- between brachialis and brachioradialis
A
- also fx of lateral epicondyle
- spared = supinator, brachioradialis
- lose: ECRL and below = drop wrist
- Sensory: below injury
19
Q
Radial entrapment
- in supinator split: Posterior interosseous N.
A
- Spared: supinator, brachioradialis, ECRL, ECRB
- Lose: extrinsic thumb, finger extensors and ECU
- no drop wrist but will radially deviate
- sensory: not affected as superficial radial n. branches proximally and above
20
Q
Radial N. entrapment
Radial head fracture
A
- Spared: supinator, brachioradialis, ECRL and ECRB
- Lose: extrinsic thumb and finger extensors and ECU
- Sensory: radial hand affected if superficial radial nerve is injured from dislocation or fracture
21
Q
Medial Nerve Course
A
- Medial and lateral cords
- medial arm
- ligament struthers
- pronator teres heads
- anterior forearm
- carpal tunnel
22
Q
Median nerve motor
A
- pronator teres
- pronator quadratus
- wrist and finger flexors except: FCU and ulnar 1/2 FDP and ulnar Lumbricals
- Thenars
23
Q
Median sensory
A
- anterior thumb side to 1/2 ring finger
- posterior tips of thumb-1/2 of ring DIP
24
Q
Median N. entrapment
ligament of struthers
A
- Lose all median Muscules
- lose all median sensation
25
# Median N. entrapment
- pronator teres heads
- Spared: Pronator teres, palmaris longus, FCR
- lose: median wrist finger flexors, pronator quadratus and thenars
- lose median sensation
26
# Median N. entrapment
pronator teres level but anterior interosseous nerve
- lose motor only
- cant do ok sign
- weakness of FPL, FDP, and pronator quadratus
- Sensation is intact *only motor nerve*
27
# Median nerve entrapment
carpal tunnel, tenosynovitis, colles fx, scaphoid fx, carpal dislocation, RA, pregnancy
- Motor loss: thenars, lumbricals 1/2,
- sensory: median N in hand but palm is spared
- palmar cutaeus branch supplies and runs over carpal tunnel
28
Ulnar nerve course
- medial cord
- medial arm
- posterior elbow - cubtial tunnel
- FCU heads
- medial forearm
- tunnel of guyan
29
Ulnar motor
- FCU
- ulnar FDP 4&5
- ulnar lumbricales 3,4
- all interossei
- hypothenars, Adductor pollicis
30
Ulnar sensory
- palmar/dorsal 1/2 ring to pinky
31
# Ulnar n. entrapment
- cubital tunnel fracture or FCU hands
- motor loss: (all ulnar): FCU, FDP 4/5, all interossei, hypothenars, adductor pollicis
- sensory loss: ulnar hand dorsal and palmar
32
# Ulnar n. entrapment
tunnel of guyan/pisaform to hook of hamate
- motor loss = ulnar intrinsics, lumbricals 3/4, all interossei, hypothenars and adductor pollicis
- Sensory: ulnar hand
33
Hand deformities related to n. injury
- drop wrist: radial n.
- ape hand: median
- Benediction hand/partial claw: ulnar
- Claw hand: both median and ulnar (intrinsic minus)
34
Wrist drop deformity
- radial n. injury in **arm**
- lose: wrist and thumb extensor and MCP extension; IPs extension intact (lumbricals and interossei)
- functional loss: wrist extesnors and active insufficiency of finger flexors
35
Radial Palsy splint
- cock up wrist
- allows finger flexion and function to grip
- aids in MCP extension function
36
Ape hand/ape thumb
- median nerve injry
- proximal forearm from: pronator teres syndrom
- at wrist from: carpal tunnel if chronic/severe, RA, carpal dislocation, colles fx
37
Ape thumb: losses
- thenars, thumb falls into plane of palm
- difficulty grasping
- losse lumbricals 1/2
- still have weak IP extension
- median n. sensation loss
- loss of fine motor
38
Ape thumb splint
- places thumb into abducted position for function while awating median n. return
39
Benediction hand or partial claw nerve and losses
- ulnar nerve
- lose: interossei, lumbricals 3,4
- hypothenars lost/weakness
- functional loss: power grip and key grip
- weak ext o f2/3 IP due to lumbricals
- MCP pulled into hyperextension due to dominance of ED
- adductor pollicis loss and weak
40
Claw hand deformity
- Lose median and ulnar nerve
- trauma, diabetes, alcoholic peripheral neuropathy
- motor: loss IP extension due to all interossei/lumbrics
- Guttering = intisic atrophy
- ape thumb
- MCP hyperextension intact
- sensation: loss ulnar and median sensory
41
claw hand deformity splinting
- counterforce to prevent MCP hyperexnteion
- position thumb in abduction
42
Sensation testing
- 2 point discrimination: alternate 1-2 points on one side of digit
- monofilaments: C bend 1.5 sec and progress thickness
43
2 point discrimination normal and what it is testing?
- normal 5 mm, 6-10 is fair and 11-15 is poor
- detecting protective sensation
44
Monofilaments normal?
- 2.44 - 2.83 is normal for hand
- 3.61 = diminished
- 4.31 = diminished; protective sensation still has pain and temperature safety but decreased manipulation of objects
- 5.07 = protective sensation level
- 6.65 = loss of protective sensation and little use of hand
45
Median nerve special tests
- anterior interosseous n. = motor only so ask if they can preform OK
46
Ulnar nerve tests
| Involvement
- froment
- ADM test
- Wartenberg
47
Froment test
- ulnar nerve
- pad to pad paper test
- if they make the ok sign then they are compensating
48
ADM test
- active abduction of 5th digit
- ulnar nerve
49
Wartenberg
- ulnar nerve
- active adduction of 5th digit from ABDucted position
50
Radial nerve test
- thumb lift off test
