MSK 1 Upper Limb Flashcards
(106 cards)
1
Q
What spinal nerve roots enter the brachial plexus?
A
C5, C6, C7, C8, T1
2
Q
Which nerves form the ‘M’ structure across the Axillary nerve?
A
Musculocutaneous
Median
Ulnar
3
Q
What spinal nerve root(s) form the Dorsal scapular nerve?
A
C5
4
Q
Which spinal nerve roots form the Long Thoracic nerve?
A
C5, C6, C7
5
Q
Which spinal root(s) form the suprascapular and subclavian nerves?
A
C5, C6
6
Q
Which nerves branch form the ‘trunks’ section of the brachial plexus?
A
Suprascapular nerve
Subclavian nerve
7
Q
Which nerves branch from the ‘roots’ section of the brachial plexus?
A
Long thoracic nerve
Dorsal scapula nerve
8
Q
Which nerve branches from the lateral cord of the brachial plexus?
A
Lateral pectoral
9
Q
Which nerves branch from the posterior cord of the brachial plexus?
A
Lower Subscapular
Medial Subscapular
Upper Subscapular
10
Q
Which nerves branch from the Medial cord of the brachial plexus?
A
Medial cutaneous nerve of the arm
Medial cutaneous nerve of the forearm
Medial pectoral nerve
11
Q
What are the 5 main branches of the brachial plexus?
A
1) Musculocutaneous nerve
2) Axillary nerve
3) Radial nerve
4) Median nerve
5) Ulnar nerve
12
Q
What are the spinal nerve roots of the Musculocutaneous nerve?
A
C5, C6, C7
13
Q
What are the spinal nerve roots of the Axillary nerve?
A
C5, C6
14
Q
What are the spinal nerve roots of the Radial nerve?
A
C5, C6, C7, C8, T1
15
Q
What are the spinal nerve roots of the Median nerve?
A
C5, C6, C7, C8, T1
16
Q
What are the spinal nerve roots of the Ulnar nerve?
A
C8, T1
17
Q
What does the Musculocutaneous nerve innervate?
A
Brachialis muscle
Biceps Brachii muscle
Coracobrachialis muscle
Skin of the lateral forearm (via Lateral cutaneous nerve of forearm)
18
Q
Which nerve innervates the coracobrachialis?
A
Musculocutaneous nerve
19
Q
Which nerve innervates the skin on the lateral edge of the forearm?
A
Lateral cutaneous nerve of the forearm (branch of the Musculocutaneous nerve)
20
Q
What does Axillary nerve innervate?
A
Glenohumeral joint
Teres minor muscle
Deltoid muscle
Skin over the regimental patch area
21
Q
Which nerve innervates Teres minor muscle?
A
Axillary nerve
22
Q
Which nerve innervates the Deltoid muscle?
A
Axillary nerve
23
Q
What does the Medial nerve innervate?
A
1st and 2nd Lumbricals Opponens pollicis Abductor pollicis brevis Flexor pollicis brevis Palmar skin Anterior forearm EXCEPT FCU and ulnar 1/2 of FDP: -Pronator teres -Flexor carpi radialis -Palmaris longus -Flexor digitorum superficialis -Medial 1/2 of Flexor digitorum profundus -Pronator quadratus -Flexor pollicis longus
24
Q
Which nerve innervates the 1st and 2nd Lumbricals?
A
Medial nerve
25
Which nerve innervates the Palmar skin?
Medial nerve
26
Which intrinsic muscles of the hand are innervated by the Median nerve?
1st and 2nd Lumbricals
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
27
What does the Radial nerve innervate?
```
Skin of posterior upper limb
Posterior compartments of the upper limb muscles:
- Triceps brachii
- Brachioradialis
- Supinator
- Anconeus
- Extensor digitorum
- Extensor pollicis longus
- Abductor pollicis longus
- Abductor pollicis brevis
- Extensor carpi ulnaris
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
- Extensor digiti minimi
- Extensor indici
```
28
Which nerve innervates the Extensor carpi ulnaris muscle?
Radial nerve
29
What does the Ulnar nerve innervate?
```
Medial 1/2 of palmar and dorsal skin (of hand)
Flexor carpi ulnaris
Ulnar 1/2 of FDP
Dorsal and Palmar interossei
3rd and 4th Lumbricals
Adductor pollicis
Hypothenar muscles:
- Opponens digiti minimi
- Abductor digiti minimi
- Flexor digiti minimi brevis
```
30
Which nerve innervates the dorsal and palmar interossei of the hand?
Ulnar nerve
31
Which nerve innervates the hypothenar muscles?
Ulnar nerve
32
What is the name of an upper brachial plexus injury (to C5-6 nerve roots)?
Erb's palsy
33
Which nerve roots are damaged in Erb's Palsy?
C5
| C6
34
What are some possible causes of an Erb's palsy?
Difficult birth (small birth canal, large baby, pulled out)
Trauma ie Motorcycle collision
= Extended angle between head and neck
35
How will someone present if they have Erb's Palsy?
- Extended, adducted and medially rotated arm
| - Flexed wrist
36
Why does Erb's Palsy cause arm to be adducted?
Damaged nerve roots of Supraspinatus nerve and Axillary nerve,
= Loss of Supraspinatus and Deltoid muscles, which are responsible for the first 90' of abduction
= unopposed adduction
37
What is the name of a lower brachial plexus injury (to C8/T1 nerve roots)?
Klumpke's palsy
38
Which nerve roots are damaged in Klumpke's Palsy?
C8
| T1
39
What are some possible causes of Klumpke's Palsy?
Fall from tree and catch branch
Difficult birth (pulled out by arm)
= Hyperextension of arm
40
How will someone present if they have Klumpke's Palsy?
'Claw hand'
- Extension of wrist
- Hyperextension of metacarpophalangeal joints
- Flexion at interphalangeal joints
41
Why does Klumpke's Palsy cause hyperextension of metacarpophalangeal joints?
Damage to Median and Ulnar nerves causes loss of the lumbricals in the hand, allowing unopposed extension of MCP joints.
42
Which nerves are at risk during a stab wound to the axilla?
Axillary nerve
| Musculocutaneous nerve
43
How would someone present if Radial nerve is damaged in the axilla?
- Wrist drop
| - Loss of sensation over posterior arm and forearm
44
What forms the apex of the axilla?
Inferior surface of clavicle
Superior border of scapula
Lateral 1st rib edge
45
What forms the base of the axilla?
Axillary fossa
Concave skin
Fascia
Subcutaneous fat
46
What forms the anterior wall of the axilla?
Pectoralis major and minor
47
What forms the posterior wall of the axilla?
```
Superiorly = Subscapularis
Inferiorly = Lattisimus dorsi and Teres major
```
48
What forms the lateral wall of the axilla?
Intertubecular sulcus of humerus
49
What forms the medial border of the axilla?
```
Serratus anterior
Thoracic wall (Ribs 1-4 and intercostal muscles)
```
50
What are the contents of the axilla?
Axillary sheath (contains brachial plexus, axillary artery and axillary vein)
Axillary lymph nodes
Coracobrachialis
Pectoralis minor
Tendons of long and short heads of biceps brachii
51
What is the superior border of the cubital fossa?
Imaginary line between the humeral epicondyles
52
What is the lateral border of the cubital fossa?
Medial side of the brachioradialis
53
What is the medial border of the cubital fossa?
Lateral side of the pronator teres
54
What forms the floor of the cubital fossa?
Brachialis and Supinator
55
What forms the roof of the cubital fossa?
Bicipital aponeurosis
Skin
Fascia
56
Which vein runs through the roof of the cubital fossa?
Medial cubital vein
57
Name the contents of the cubital fossa from lateral to medial:
- Tendon of biceps brachii
- Brachial artery
- Median nerve
(Median cubital vein also runs in roof of cubital fossa)
58
Where is the weakest point of the clavicle?
Between the medial 2/3rd and lateral 1/3rd.
59
How does someone usually appear with a clavicular fracture?
- Supporting affected arm with other arm
- Medial 2/3rds of clavicle pulled superiorly
- Lateral 1/3rd of clavicle pulled inferiorly and medially
- Shortened clavicle
60
Why is the medial fragment of the clavicle pulled superiorly when fractured?
Strong sternocleidomastoid muscle pulled the broken fragment superiorly
61
Why is the lateral fragment of the clavicle pulled inferiorly and medially when fractured?
Weight of upper limb pulls it inferiorly
| Strong pectoralis major muscle pulls it medially
62
What is the most common cause of a clavicular fracture?
Fall on outstretched hand
63
Which part of the brachial plexus is at risk during a clavicular fracture?
Lateral and Medial cords
64
What is the most common treatment for a clavicular fracture?
Sling
65
What is the most common causes of a surgical neck fracture of the humerus?
Direct trauma
| Fall on outstretched hand
66
Which neurovascular structures are at risk during a surgical neck fracture of the humerus?
Axillary nerve
| Anterior and Posterior Circumflex Humeral Arteries
67
Which neurovascular structure is most at risk during a mid-shaft humeral fracture?
Radial nerve
68
Which neurovascular structure is most at risk during a supra-condylar humeral fracture?
Median nerve
69
Which neurovascular structure is most at risk during avulsion of the medial epicondyle of the humerus?
Ulnar nerve
70
What is 'cubital tunnel syndrome'?
Compression of ulnar nerve in the cubital tunnel
71
Which 3 structures form the cubital tunnel?
1) Olecranon of the Ulna
2) Medial epicondyle of the humerus
3) Flexor carpi ulnaris tendon
72
What structure passes through the cubital tunnel?
Ulnar nerve
73
What is the difference between extrinsic and intrinsic muscles of the hand?
Extrinsic muscles originate from outside the hand - anterior or posterior compartments of the forearm
Intrinsic muscles originate from within the hand
74
Name the muscles forming the Thenar eminence from lateral to medial:
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
75
Which nerve innervates the Thenar eminence
Median nerve
76
Name the muscles forming the Hypothenar eminence:
Opponens digiti minimi
Abductor digiti minimi
Flexor digiti minimi brevis
77
Which nerve innervates the Hypothenar eminence?
Ulnar nerve
78
Where do the lumbricals originate from?
Flexor digitorum profundus
79
What is the main actions of the lumbricals?
Flexion at the metocarpophalangeal joints
| Extension at the interphalangeal joints
80
What nerves innervate the lumbricals?
Median nerve
| Ulnar nerve
81
What is the main action of the palmar interossei?
Adduction of the digits
82
What is the main action of the dorsal interossei?
Abduction of the digits
83
What nerve innervates the interossei of the hand?
Ulnar nerve
84
Which intrinsic muscles of the hand are missing from the following list:
- Thenar eminence
- Hypothenar eminence
- Lumbricals
- Interossei
- Palmaris brevis
| - Adductor pollicis
85
Which nerve innervates the Palmaris brevis and Adductor pollicis muscles?
Ulnar nerve
86
What is an Allen's test, and why is it performed?
Occlusion of radial and ulnar arteries at wrist joint to test perfusion of the hand, ie before radial artery harvesting.
87
Which artery enters the hand dorsally?
Radial artery
88
What crosses the floor of the anatomical snuffbox?
Radial artery
89
Which part of the hand is mainly supplied by the radial artery?
1st and 2nd digits
90
Which part of the hand is mainly supplied by the ulnar artery?
2nd, 3rd, 4th and 5th digits
91
Which artery enters the hand superior to the flexor retinaculum?
Ulnar artery
92
What is the name of the canal through which the Ulnar artery passes to enter the hand?
Guyon's canal
93
What can commonly cause flexor tendon sheath inflammation?
- Infection via skin wound (splinter etc)
- Arthritis
- Overuse
- Diabetes
94
Which flexor sheaths have a greater risk of transmitting infection through the carpal tunnel, and why?
Thenar and hypothenar flexor sheaths, as are continuous with radial and ulnar bursae
95
Where would you test the dermatome of the spinal root C5?
Regimental badge area
96
Where would you test the dermatome of the spinal root C6?
Tip of thumb
97
Where would you test the dermatome of the spinal root C7?
Tip of middle finger
98
Where would you test the dermatome of the spinal root C8?
Tip of index finger
99
Where would you test the dermatome of the spinal root T1?
Middle medial anterior forearm
100
Where would you test the dermatome of the spinal root T2?
Axilla
101
How would you test the myotome for the spinal root C4?
Shoulder elevation
102
How would you test the myotome for the spinal root C5?
Shoulder abduction
103
How would you test the myotome for the spinal root C6?
Elbow flexion
104
How would you test the myotome for the spinal root C7?
Elbow extension
105
How would you test the myotome for the spinal root C8?
Finger flexion
106
How would you test the myotome for the spinal root T1?
Finger abduction
