chapter 21 Flashcards
1
Q
Certain peripheral nerves are at an increased risk of injury due to their ANATOMICAL LOCATION what are they?
A
1) Superficial positioning of the nerve
2) nerve coursing through an area of trauma
3) Narrow pathways through bony or fibrous tissue canals
2
Q
Damage to this area results in paralysis of the serratus anterior muscle. what area is this?
A
Long thoracic nerve
3
Q
Without a functional serratus anterior, the scapula is not held against the thoracic wall. This is clinically referred to as?
-this also results in difficulty elevating the upper extremity above the horizontal plane
A
Winged scapula
4
Q
Compression at the SUPRASCAPULAR NOTCH will affect the following muscles?
A
1) Supraspinatus
2) infraspinatus
5
Q
Damage occurring at the SPINE OF SCAPULA will affect the following muscles:
A
Infraspinatus
6
Q
Damage to the supraspinatus results in?
A
difficulty in abducting the arm at the shoulder
7
Q
Damage to the Infraspinatus due to the SUPRASCAPULAR NOTCH results in?
A
Weakness with lateral rotation of the arm at the shoulder
8
Q
Damage to the Infraspinatus due to the SPINE OF SCAPULA results in?
A
Weakness with lateral rotation of the arm at the shoulder
9
Q
Damage to the medial brachial cutaneous nerve (MBC) results in:
A
there is a lack of sensation to the medial forearm
10
Q
Damage to the axillary nerve results in:
A
1) Shoulder weakness (except for adduction of the arm at the shoulder)
2) Sensory loss BELOW the LATERAL PART of the shoulder
11
Q
Non-traumatic compression of the medial nerve is predominantly caused by
A
slowly expanding lesions that are often vascular in nature
12
Q
Traumatic compression of the medial nerve such as __________________ may lead to medial nerve injury
A
SUPRACONDYLAR fracture
13
Q
Common neuropathies associated with median nerve include:
A
1) PRONATOR syndrome
2) ANTERIOR interosseous nerve syndrome
3) CARPAL tunnel sundrome
14
Q
What is a compression of the MEDIAL NERVE that occurs PROXIMALLY, near the area of the ELBOW called?
A
Pronator syndrome
15
Q
Pronator syndrome is commonly mistaken for?
A
carpal tunnel syndrome
16
Q
In pronator syndrome women are affected _______ times more often than men and it typically presents in the fifth decade of life
A
4
17
Q
Anatomy:
After souring through the MEDIAL COMPARTMENT of the ARM, the median nerve enters the ________________ and gives off the ANTERIOR INTEROSSEOUS NERVE (AIN). As the median nerve passes into the forearm, it gives supply to the pronator teres muscle and then courses between this muscles _______ heads of origin
-As a result, the pronator teres is usually _______, as it receives its innervation before it is pierced by the nerve
The nerve descends through the forearm, BETWEEN the flexor digitorum superficialis and _________________ muscles. ______________ to the flexor retinaculum, the median nerve gives off a _________________ that courses ANTERIOR to the flexor retinaculum to CUTANEOUS innervate the skin of the __________________. The medial nerve then courses THROUGH the _______________ and enters the hand
A
1) Cubital fossa
2) 2
3) Spared
4) flexor digitorum profundus
5) Proximal
6) palmer branch
7) Lateral palm
8) Carpal canal
18
Q
(Site of compression of the median nerve)
Sites of compression of the median nerve may be located near or within the ___________, as well as the proximal anterior forearm region.
A
cubital fossa
19
Q
Potential sites compression of the medial nerve include the :
A
1) Ligament of struthers
2) Bicipital aponeurosis or lacertus fibrosis
3) Pronator teres muscle
4) Arch of the flexor digitorum superficialis
20
Q
What is the ligament that lies between an anomalous supracondylar tubercle and the medial epicondyle called?
A
Ligament of struthers
21
Q
What is the part of the insertion of the biceps brachii muscle called?
A
Bicipital aponeurosis or lacertus fibrosis
22
Q
This is when the median nerve pierces between its two heads of origin?
A
Pronator teres muscles
23
Q
This is when the median nerve passes deep to the arch of this muscle, which is located between its origins?
A
Arch of the flexor digitorum superficialis
24
Q
1) easy fatigability of the proximal anterior forearm
2) TENDERNESS over the pronator teres muscles
3) Aching pain in the proximal anterior forearm associated with repetitive motions that cause HYPERTONICITY in the pronator teres
—— Repetitive motions include occupational activities such as hammering , shucking oysters, continual manipulation of tools
4) pain on resistance to PRONATION of the pronator teres muscle and resistance to FLEXION of the flexor digitorum superficialis muscle of digits 3 and 4
These symptoms are associated with what disease?
A
Pronator syndrome
25
1) Numbness or paresthesia (a burning or prickling sensation) in the median nerve distribution
2) Positive TINEL'S test (digital tingling on percussion) over the proximal forearm, which typically takes 4-5 MONTHS to develop
3) These symptoms of this disease are insidious in onset, causing a DELAY in diagnosis that ranges from 9 MONTHS to 2 YEARS
These clinical presentation are associated with what disease?
pronator syndrome
26
(Pronator syndrome) Weakness or lack of function of the:
1) Flexor digitorum superficialis muscle of digits ____ and ____ (flexion of digits ___ and ____)
2) Flexor carpi radialis muscle ( flexion and abduction of the hand and wrist)
3) Palmaris longus muscle (weak flexion of hand at the wrist)
4) Palmar branch of the median nerve ( cutaneous supply of the __________)
1) 3
2) 4
3) 3
4) 4
5) Lateral palm
27
Important (Pronator syndrome) Associated deficits:
1) As a proximal or high lesion, this syndrome will also present with the clinical deficits of a ____________
Thus, in addition to the symptoms of pronator syndrome, the patient will also exhibit the symptoms of ___________________
furthermore, if compression of the median nerve occurs _________ to the location where the AIN branches off of the median nerve- at the pronator teres muscle, the ligament of struthers, or the bicipital aponeurosis- the patient will also present clinical deficits of __________________
1) distal lesion
2) carpal tunnel syndrome
3) proximal
4) Anterior interosseous nerve syndrome
28
AIN syndrome is also called KILOH-NEVIN syndrome. It is a compression of the AIN that occurs along its pathway within the ________________. The AIN is purely ___________ therefore, there is no ____________ disturbance associated with the compression of this nerve. This syndrome can be the result of an injury to the __________ by direct trauma, compression or inflammation of the AIN. AIN accounts for fewer than ____ of all upper extremity neuropathies
1) Anterior forearm
2) motor
3) sensory
4) forearm
5) 1%
29
(Anatomy of AIN syndrome)
After coursing through the _______________ of the ________ the median nerve enters the _____________ and gives off the AIN. The AIN courses distally along the ____________ of the interosseous membrane, BETWEEN the flexor digitorum profundus muscles
1) medial compartment
2) arm
3) cubital fossa
4) anterior surface
30
(site composition of AIN syndrome)
Although uncommon, nearby muscular or neurovascular structures may apply pressure on the anterior interosseous nerve, compressing it against the __________________
anterior interosseous membrane
31
Symptoms of AIN syndrome
1) Vague pain in the proximal forearm and ______ that increases with activity, especially repetitive forearm motion. This pain can be relieved by rest
2) Difficulty with ___________ or picking up small objects
3) An unusual pinch demonstrated by the ____________ interphalangeal (IP) joint of the __________ and the distal interphalangeal (DIP) joint of the _________
1) Wrist
2) writing
3) hyperextended
4) Thumb
5) index finger
32
Clinical presentation of AIN syndrome:
1) the patient has difficulty with producing the ___ sign due to the hyperextened DIP joint of the index finger
2) The ________________ muscle is the FIRST muscle affected
3) Weakness or paralysis more commonly occurs with the ___________________ muscle and ___________________ muscle of the index finger (digit 2)
4) Weakness or paralysis less commonly with the middle finger (digit 3) and the _______________ muscle
1) Ok
2) Flexor pollicis longus muscle
3) flexor pollicis longus
4) flexor digitorum profundus
5) pronator quadratus
33
(AIN syndrome)
Weakness or lack of function of the:
1) flexor pollicis muscle (__________ of the thumb at the IP joint)
2) Flexor digitorum profundus muscle of the digits _____ and _____ ( flexion of the digits ____ and ___ at the DIP
3) ______________ (pronation of forearm at the wrist)
1) flexion
2) 2
3) 3
4) 2
5) 3
6) pronator quadratus muscle
34
Carpal tunnel is a syndrome in which compression of the _____________ occurs DISTALLY at the _________. it is also known as __________ syndrome.
1) medial nerve
2) wrist
3) carpal canal syndrome
35
What is the most common nerve entrapment?
carpal tunnel syndrome
36
carpal tunnel affects ______ of the ________ population and ________ of individuals in __________ settings
1) 1-3%
2) general
3) 5-15%
4) industrial
37
What syndrome is more commonly occurs in patients who are middle age, female, diabetic, smokers and obese?
carpal tunnel
38
(Carpal tunnel anatomy)
The median nerve courses THROUGH the ___________ and enters the hand. The ______________ is also known as the transverse carpal ligament. it covers the arch of the carpal bones into a canal through which the __________ courses. this is known as the ___________________.
-the lateral attachment of the flexor retinaculum consists of the ___________ and the __________.
- the medial attachment of the flexor retinaculum consists of the ________, the __________ and the __________
1) carpal canal
2) flexor retinaculum
3) median nerve
4) carpal tunnel or carpal canal
5) Scaphoid
6) trapezium
7) Pisiform
8) triwuetrum
9) hook of hamate
39
The contents of the carpal canal include:
1)
2)
3)
1) 9 muscle tendons (4 tendons of flexor digitorum superficialis, 4 tendons of flexor digitorum profundus, and 1 tendon of flexor pollicis longus)
2) 2 bursae ( the radial and ulnar bursae)
3) 1 nerve ( medial nerve)
40
(Site of composition)
Carpal tunnel syndrome occurs due toa compression of the ___________ the flexor retinaculum in the carpal canal
medial nerve under
41
What are the symptoms of mild carpal tunnel syndrome?
1) OCCASIONAL tingling and numbness
2) awakening at night, usually intermittent
3) symptoms increase with activity
4) function is not significantly impaired
5) little or no decrease in GRIP and pinch strength
42
What are the symptoms of moderate carpal tunnel syndrome?
1) regularly occurring tingling and numbness
2) decreased ability to distinguish between hot and cold
3) awakening at night with activity
4) NUMBNESS or pain when driving or reading
5) Some impairment: decreased sweat
6) DECREASE grip and pinch strength
43
What are the symptoms of severe carpal tunnel syndrome?
1) CONSTANT numbness during the day and night
2) sensory symptoms are persistent
3) Function is significantly impaired
4) nerve is TENDER to deep pressure
5) significant and often debilitating decrease in grip and pinch strength
6) dropping things
7) inability to perform certain ADL's (activities of daily living)
44
Clinical presentation of mild carpal tunnel syndrome:
1) POSITIVE provocative (PINEL'S and PHALENS)
2) NO muscle atrophy
3) Middle finger most commonly involved
45
Clinical presentation of MODERATE carpal tunnel syndrome:
1) POSITIVE provocative (PINEL'S and PHALENS)
2) Weakness of the thenar muscle, but not atrophy
3) middle finger and other areas of median nerve distribution may be involved
46
Clinical presentation of SEVERE carpal tunnel syndrome:
1) TINEL'S and PHALENS may be NEGATIVE
2) Thenar ATROPHY
3) entire distribution of the median nerve is impacted
47
Carpal tunnel causes weakness or lack of function of the:
1) Abductor pollicis brevis muscle (abduction of the thumb)
2) Flexor pollicis brevis muscle (superficial head and flexion o the thumb)
3) Opponens pollicis muscle (opposite of the THUMB)
4) Lumbricals (Digits 2 and 3) (Z-POSITION)
5) Digital branches of the median nerve (cutaneous supply of the LATERAL 3.5 DIGITS ANTERIORLY AND THEIR TIPS POSTERIORLY)
48
Compression neuropathies of the ulnar nerve:
1) the pathway of the ulnar nerve makes it especially vulnerable to compression
2) common neuropathies associated with the ulnar nerve include:
1) CUBITAL tunnel syndrome
2) Guyon's canal syndrome
49
Cubital tunnel syndrome most often occurs in the?
right upper extremity
50
Cubital tunnel syndrome
-Middle are men are affected _____ more often than women
3 times
51
Cubital tunnel syndrome
-trauma to this nerve can be?
direct or indirect
52
__________ to the nerve in the cubital tunnel may occur with fractures to the humerus or dislocation of the elbow joint
direct trauma
53
_________ in cubital tunnel syndrome may occur with prolonged resting of the elbow on a hard surface or repetitive flexion motion of the elbow
indirect trauma
54
The ulnar nerve courses through the ____________ of the ____ and pierces the _____________ of the _________________ as it passes from _______ to ______ comaprtment of the ____. The nerve then courses ____________ to the _______ of the humerus. It passes through the ___________ and passes BETWEEN the two heads of origin of the flexor carpi ulnaris muscle. In the distal forearm, the ulnar nerve gives off a ____ that CUTANEOUSLY innervates the ________ of the _____________________________.
_____________ to the flexor retinaculum, the ulnar nerve also gives off a ___________________ that courses _______________ to the flexor retinaculum to CUTANEOUSLY innervate the
1) medial compartment
2) arm
3) posterior lamina
4) medial intermuscular septum
5) medial
6) posterior
7) arm
8) posterior
9) medial epicondyl
10) cubital tunnel
11) dorsal
12) MEDIAL 1.5 digits and hand
13) proximal
14) palmer branch
15) anterior
16) skin of the MEDIAL PALM
55
Sites of compression of the ulnar nerve may be located in the?
elbow region
56
Compression of the ulnar nerve, may result in the?
Cubital tunnel syndrome
57
Potential sites of compression of the ulnar nerve include:
1) medial intermuscular septum
2) medial epicondyle
3) cubital tunnel
4) flexor carpi ulnaris
5) deep flexor pronator aponeurosis
58
The ulnar nerve pierces the ___________ in order to pass from the MEDIAL to POSTERIOR compartment of the ARM
medial intermuscular septum
59
The ulnar nerve courses POSTERIOR to this bony prominence found on the medial side of the distal humerus. What is this?
Medial epicondyle
60
The ulnar nerve passes through the fibro-osseous canal which is formed by the ulnar collateral ligament, trochlea of the humerus, and medial epicondylar groove of the humerus. The roof of this canal is formed by the triangular arcuate ligament, which is also known as Osborne's ligament. What is this structure?
cubital tunnel
61
The ulnar nerve passes between the two heads of origin of the _________________
Flexor carpi ulnaris muscle
62
The ulnar nerve passes deep to the ____________ about 5cm distal to the medial epicondyle. the _____________ lies on the medial side of the forearm.
Deep flexor pronator aponeurosis
63
Symptoms of cubital tunnel syndrome?
1) pain at the medial elbow
2) decrease ability in FLEXION of the wrist
3) Decrease ability in ADDUCTION of the wrist
4) weak grip and lateral pinch
5) Decrease ability or inability to cross fingers or spread them apart
64
Clinical presentation of cubital tunnel syndrome:
1) Positive _________ at the cubital tunnel
2) Weak intrinsic of the hand
3) Positive ____________ sign in the advance stage
4) The hand to be drawn ___________ while flexing the wrist. This results from an imbalance due to an _________________________________
5) ______________ disturbance (numbness, paresthesia, dysesthesia) over the SKIN of the ________________ (hypothenar eminence), as well as the dorsum of the _________________ and hand
1) Positive TINEL's at the cubital tunnel
2) Weak intrinsic of the hand
3) Positive FROMENT's sign in the advance stage
4) The hand to be drawn LATERALLY while flexing the wrist. This results from an imbalance due to an INACTIVE FLEXOR CARPI ULNARIS AND AN ACTIVE FLEOR CARPI RADIALIS
5) SENSORY disturbance (numbness, paresthesia, dysesthesia) over the SKIN of the MEDIAL PALM (hypothenar eminence), as well as the dorsum of the MEDIAL 1.5 digits and hand
65
(Cubital tunnel syndrome)
Weakness or lack of function of the:
1. Flexor carpi ulnaris muscle (weakened flexion and adduction of the hand at the wrist)
2. Flexor digitorum profundus muscle of digits __ and ___ (weakened flexion of digits __ and ____)
3. Palmer branch of the ulnar nerve (cutaneous supply of the _______)
4. Dorsal branch of the ulnar nerve (cutaneous supply of the _______ of the _____________)
1. Flexor carpi ulnaris muscle (weakened flexion and adduction of the hand at the wrist)
2. Flexor digitorum profundus muscle of digits 4 and 5 (weakened flexion of digits 4 and 5)
3. Palmer branch of the ulnar nerve (cutaneous supply of the MEDIAL PALM)
4. Dorsal branch of the ulnar nerve (cutaneous supply of the dorsum of the MEDIAL 1.5 DIGITS and HAND)
66
(cubital tunnel syndrome)
Associated deficits
1.As a proximal or high lesion, this syndrome will also present with the clinical deficits of a ________ lesion
a.Thus, in addition to the symptoms of cubital tunnel syndrome, the patient will also exhibit the symptoms of Guyon’s canal syndrome
Associated deficits
1. As a proximal or high lesion, this syndrome will also present with the clinical deficits of a distal lesion
a. Thus, in addition to the symptoms of cubital tunnel syndrome, the patient will also exhibit the symptoms of _______________ syndrome
67
Guyon’s canal syndrome
General information:
i. Guyon’s canal syndrome is also called ______________. It is a compression of the _______ nerve that occurs distally at the region of the _______
Guyon’s canal syndrome
General information:
i. Guyon’s canal syndrome is also called HANDLEBAR PALSY. It is a compression of the _________ nerve that occurs distally at the region of the _________
68
Guyon's canal syndrome
Anatomy:
i. The ulnar nerve travels distally in the anterior forearm BETWEEN the flexor carpi ulnaris and flexor digitorum profundus muscles
ii. It then courses through the Guyon’s canal in the wrist, ____________ to the ______________
iii. ___________ to the pisiform bone, the ulnar nerve divides into two branches, the superficial and deep branches
Guyon's canal syndrome
Anatomy:
i. The ulnar nerve travels distally in the anterior forearm BETWEEN the flexor carpi ulnaris and flexor digitorum profundus muscles
ii. It then courses through the Guyon’s canal in the wrist, ANTERIOR to the CARPAL TUNNEL
iii. LATERAL to the pisiform bone, the ulnar nerve divides into two branches, the superficial and deep branches
69
Guyon's canal syndrome
Site of compression
i. Compression of the ulnar nerve at Guyon’s canal is usually associated with trauma, anomalous muscles or abnormal structures (ganglion cyst or lipoma). Compression can also be due to fractures of the _________ or metacarpal bones of digits __ or ___
c. Site of compression
i. Compression of the ulnar nerve at Guyon’s canal is usually associated with trauma, anomalous muscles or abnormal structures (ganglion cyst or lipoma). Compression can also be due to fractures of the HAMATE or metacarpal bones of digits 4 or 5
70
Symptoms of Guyon’s canal syndrome
i. Weakness or paralysis of the hand intrinsic innervated by the ulnar nerve
ii. Cold intolerance in digits __ and __
Symptoms of Guyon’s canal syndrome
i. Weakness or paralysis of the hand intrinsic innervated by the ulnar nerve
ii. Cold intolerance in digits 4 and 5
71
Clinical presentation of Guyon’s canal syndrome
i. Possible Positive ____________ guyon’s canal
ii. __________ hand deformity due to the atrophy of the interosseous muscles and lumbricals 3 and 4 appears as:
1. _____________ of interphalangeal joints of digits 4 ang 5 resulting from an unopposed flexor digitorum profundus muscle
2. ______________ of the MCP joint of digits 4 and 5 resulting from an unopposed extensor digitorum muscle
iii. Difficulty in making a fist
iv. Motor and sensory deficits are present distal to Guyon’s canal
1. There will be a sensory deficit to the ____________________________
Clinical presentation of Guyon’s canal syndrome
i. Possible Positive TINEL'S guyon’s canal
ii. CLAW hand deformity due to the atrophy of the interosseous muscles and lumbricals 3 and 4 appears as:
1. FLEXION of interphalangeal joints of digits 4 ang 5 resulting from an unopposed flexor digitorum profundus muscle
2. EXTENSION of the MCP joint of digits 4 and 5 resulting from an unopposed extensor digitorum muscle
iii. Difficulty in making a fist
iv. Motor and sensory deficits are present DISTAL to Guyon’s canal
1. There will be a sensory deficit to the MEDIAL 1.5 DIGITS of the HAND, ANTERIORLY
72
Classification of Guyon’s canal syndrome
i. Type I: involvement of the __________ muscle and the ________ branch of the ulnar nerve
ii. Type II: involvement of the ________ branch of the ulnar nerve
iii. Type III: involvement of the ____________ sensory branch of the ulnar nerve
Classification of Guyon’s canal syndrome
i. Type I: involvement of the HYPOTHENAR muscle and the DEEP branch of the ulnar nerve
ii. Type II: involvement of the DEEP branch of the ulnar nerve
iii. Type III: involvement of the SUPERFICIAL sensory branch of the ulnar nerve
73
Guyrons canal syndrome causes weakness or lack of function of the:
i. Abductor digiti minimi muscle (abduction of digit 5)
ii. Flexor digiti minimi brevis muscle (flexion of digit 5)
iii. Opponens digiti minimi muscle (drawing digit 5 forward)
iv. Lumbricals (digits 4 and 5 Z-POSITION)
v. Interossei muscles (palmari dorsal)
1. Palmar (ADDUCTION of digits)
2. Dorsal (ABDUCTION of the digits)
vi. Flexor pollicis brevis muscle (adduction of the thumb)
vii. Superficial branch of the ulnar nerve for cutaneous supply of the MEDIAL 1.5 DIGITS, ANTERORLY
74
Compression of the radial nerve
a) The radial nerve and its primary motor branch, the ________________, are less vulnerable to compression compared to the median nerve at the carpal tunnel, or the ulnar nerve at the cubital tunnel
POSTERIOR INTEROSSEOUS (PIN)
75
Common neuropathies of the radial or posterior interosseous nerve include:
a. Axilla-crutch palsy, Saturday night palsy
b. Radial groove compression
c. Posterior interosseous nerve (PIN) syndrome
76
Compression of the radial nerve occurs at the axilla what syndrome is this?
Axilla -cruth palsy. Saturday night palsy
77
occurs from pressure of a crutch pressing against the radial nerve
i. Axilla-crutch palsy
78
commonly occurs when an intoxicated person’s arm is slumped over the back of a chair for an extended amount of time, causing pressure on the radial nerve
ii. Saturday night palsy
79
Anatomy (compression of the radial nerve)
The radial nerve is the continuation of the ________________ of the brachial plexus, beginning after the axillary nerve is given off
Posterior cord
80
a. Compression of the radial nerve in the axilla is caused by pressure on the nerve as it is pushed against the proximal humerus and __________
scapula
81
Symptoms of axilla-crutch palsy and Saturday night palsy include:
a.Symptoms include loss of function of the radial nerve distal to the axilla
b. Difficult with EXTENSION of the forearm at the elbow, wrist, and fingers
c. Sensory deficit to the skin on the arm and forearm, posteriorly
82
Clinical presentation of axilla-crutch palsy and Saturday night palsy
a. Motor deficit includes an inability to perform motor movement
b. Sensory deficit includes numbness and tingling of the posterior upper limb
83
Damage to radial nerve at the proximal arm:
Triceps brachii muscle (extension of the forearm at the elbow)
84
Associated deficits due to damage to radial nerve:
-As a proximal or high lesion, this symptom will also present with the clinical deficits of a ____________
-Thus, in addition to the symptoms of axilla- crutch palsy and Saturday night palsy the patient will also exhibit the symptoms of __________________________ and __________________
1) distal lesion
2) radial GROOVE compression
3) Posterior interosseous nerve (PIN) syndrome
85
radial nerve compression at the radial groove is typically due to trauma to the ________
posterior arm
86
Anatomy (radial groove compression)
a. The nerve courses from ________________ in the radial groove of the humerus which is located in the ___________________________
b. It then passes distally toward the elbow region where it is found on the _____________ of the ______________
c. The nerve then pierces the _____________________ as it passes from the ____________ to the ________________________ of the _____
d. BETWEEN the brachialis muscles, the radial nerve divides into its 2 terminal branches
i. Superficial branch of the radial nerve
ii. Deep branch of the radial nerve
e. While the superficial branch of the radial nerve courses distally to the wrist area, the _________ branch of the radial nerve enters the __________________ of the supinator muscle and changes its name to the ___________________________
Anatomy (radial groove compression)
a. The nerve courses from MEDIAL TO LATERAL in the radial groove of the humerus which is located in the POSTERIOR COMPARTMENT of the ARM
b. It then passes distally toward the elbow region where it is found on the LATERAL SIDE of the CUBITAL FOSSA
c. The nerve then pierces the LATERAL INTERMUSCULAR SEPTUM as it passes from the POSTERIOR to the ANTERIOR COMPARTMENT of the ARM
d.Between the brachialis muscles, the radial nerve divides into its 2 terminal branches
i. Superficial branch of the radial nerve
ii. Deep branch of the radial nerve
e. While the superficial branch of the radial nerve courses distally to the wrist area, the DEEP branch of the radial nerve enters the SUPERIOR BORDER of the supinator muscle and changes its name to the POSTERIOR INTEROSSEOUS NERVE (PIN)
87
Compression of the radial nerve in the posterior compartment of the arm may occur as a result of:
i. Entrapment of the nerve due to a broken humerus
ii. Vascular compression of the nerve due to pressure from adjacent arteries
88
4. Symptoms of radial groove compression
a. Pain in the distal arm and the LATERAL elbow
b. Wrist DROP
i. Wrist drop occurs as there is an inability to extend the wrist. Proximal forearm muscles do not receive innervation and thus cannot perform the action of wrist extension
89
Clinical presentation for radial nerve entrapment:
Nerve entrapments occurring PROXIMAL to the branches that innervate muscles acting to extend the hand at the wrist lead to wrist drop
90
Damage to radial nerve at mid arm:
i. Brachioradialis muscle (flexion of the forearm at the elbow)
ii. Extensor carpi radialis longus muscle (EXTENSION AND ABDUCTION of the hand at the wrist)
iii. Anconeus muscle (extension of the forearm at the elbow)
91
Damage to superficial branch of radial nerve:
Sensory deficit to the skin on the LATERAL HALF of the DORSUM of the hand, and the proximal portion of the LATERAL 3.5 DIGITS, POSTERIORLY
92
Damage to deep branch of radial nerve:
Extensor carpi radialis brevis muscle (extension and abduction of the hand at the wrist)
93
As a middle lesion, radial groove compression will also present with the clinical deficits of distal lesion:
Thus, in addition to the symptoms of radial groove compression, the patient will also exhibit the symptoms of Posterior interosseous nerve (PIN) syndrome
94
a. PIN syndrome is also known as ___________________. It is a compression of the __________________________ or its branches that occurs at the _____________________ region
b. The PIN is purely _____________. Since it does not provide sensory innervation, there is no sensory disturbance associated with the compression of this nerve
c. Compression is typically associated with repeated or strenuous efforts involving supination and pronation
a. PIN syndrome is also known as RADIAL TUNNEL SYNDROME. It is a compression of the POSTERIOR INTEROSSEOUS NERVE or its branches that occurs at the PROXIMAL FOREARM region
b. The PIN is purely MOTOR. Since it does not provide sensory innervation, there is no sensory disturbance associated with the compression of this nerve
c. Compression is typically associated with repeated or strenuous efforts involving supination and pronation
95
a. As the deep branch of the radial nerve enters the __________________ of the supinator muscle, its name changes to _________________________________
b. PIN courses distally into the forearm innervating ______________________
c. It does not enter the __________________
a. As the deep branch of the radial nerve enters the SUPERIOR BORDER of the supinator muscle, its name changes to POSTERIOR INTEROSSEOUS NERVE
b. PIN courses distally into the forearm innervating 8 MUSCLES
c. It does not enter the HAND
96
(PIN) Posterior interosseous nerve syndrome
The most frequent site of compression is in the _____________________, ____________ to the supinator muscle
The most frequent site of compression is in the PROXIMAL FOREARM, DEEP to the supinator muscle
97
Symptoms of posterior interosseous nerve syndrome are the following:
a. Weakness of wrist extension
i.The action of extension can still occur from the extensor carpi radialis longus muscle, which is supplied by the radial nerve and the extensor carpi radialis brevis muscle, which is supplied by the deep branch of the radial nerve
b. Decreased ability or inability to extend the thumb and digits
98
Clinical presentation for radial nerve entrapment
Patient exhibits weakness or an inability to extend digits against resistance
99
(Weakness or lack of function of:)
Damage to PIN at the proximal forearm:
i. Extensor digitorum muscle (extension of digits 2-5)
ii. Extensor digiti minimi muscle (extension of digit 5)
iii. Extensor carpi ulnaris muscle (extension and ADDUCTION of wrist)
iv. Abductor pollicis longus muscle (ABDUCTION and extension of thumb)
v. Extensor pollicis brevis muscle (extension of the thumb)
vi. Extensor pollicis longus muscle (extension of thumb)
vii. Extensor indicis muscle (extension of digit 2** )
viii. Supinator muscle (supination of the forearm)
100
1) All the following are anatomical risk factors for peripheral nerve injuries EXCEPT?
a. Deep positioning of the nerves
b. Narrow pathways through bony canals
c. Nerves course through areas of trauma
a. Deep positioning of the nerves
101
2) Which of the following is incorrect?
a. Damage to the long thoracic nerve results in difficulty elevating the upper extremity above the horizontal plane
b. Compression at the suprascapular notch will result in difficulty with abduction and lateral rotation of the arm at the shoulder
c. Damage occurring at the spine of the scapula will affect the supraspinatus and infraspinatus muscles
d. Damage to the axillary nerve results in a loss of sensation below the lateral part of the shoulder
c. Damage occurring at the spine of the scapula will affect the supraspinatus and infraspinatus muscles
102
3) Which of the following statements is CORRECT?
a. Carpal tunnel affects 5-15% of the general population and 1-3% of individuals in industrial settings
b. The flexor pollicis brevis is the first muscle affected in anterior interosseous nerve (AIN) syndrome
c. Decreased ability in flexion and adduction of the wrist is associated with pronator syndrome (wrong answer)
d. The anterior interosseous nerve (AIN) is purely motor in nature and causes no sensory disturbances when damaged
d. The anterior interosseous nerve (AIN) is purely motor in nature and causes no sensory disturbances when damaged
103
4) Which of the following statements is INCORRECT?
a. The medial attachment of the flexor retinaculum consists of the pisiform, the trapezium, and the hook of hamate
b. The contents of the carpal canal include 2 bursae and 1 nerve
c. Men are two times more likely than women to suffer from posterior interosseous nerve (PIN) syndrome (Wrong answer)
d. The flexor retinaculum is also known as the transverse carpal ligament
a. The medial attachment of the flexor retinaculum consists of the pisiform, the trapezium, and the hook of hamate
104
5) Which of the following statements is incorrect?
a. The radial nerve and posterior interosseous nerve (PIN) are less vulnerable to compression compared to the median and ulnar nerve
b. Guyon’s canal syndrome type II involved the superficial branch of the ulnar nerve
c. Tinel’s and Phalen’s tests may be negative if a patient has severe carpal tunnel syndrome
d. Kiloh-Nevin syndrome results from compression of the anterior interosseous nerve (AIN) that occurs along its pathway within the anterior forearm
b. Guyon’s canal syndrome type II involved the superficial branch of the ulnar nerve
