Arm and Forearm Flashcards
1
Q
How many muscles are there in the arm?
A
Four + one*
2
Q
How many fascial compartments in the arm?
A
Two
3
Q
How many large nerves are there in the arm?
A
Three
4
Q
How many neuromuscular bundles are there?
A
One large medial neuromuscular bundle
5
Q
What structures are present in the biceps brachii?
A
The short head
The long head
The bicipital aponeurosis
6
Q
What bony attachments are present in the anterior aspect of the arm?
A
The radial tuberosity and coronoid on the ulna
7
Q
Where does the short head of the biceps brachii originate?
A
The coracoid process
8
Q
Where does the long head of the biceps brachii originate?
A
Supraglenoid tubercle superior to the glenoid fossa
9
Q
Other than the biceps, what are the muscles of the anterior aspect of the arm?
A
The coracobrachialis - flexion and adduction + a little bit of lateral rotation of the arm (found by the biceps)
The brachialis - flexion of the elbow joint at the cubital fossa
10
Q
What does the brachial do and what nerve roots innervate it?
A
– Prime mover in elbow flexion
– C5,C6
11
Q
What does the brachial do and what nerve roots innervate it?
A
– Prime mover in elbow flexion
– C5,C6
12
Q
What does the corachobrachialis do and what nerve roots innervate it?
A
– Flexion adduction at GH joint
• Stability
– C5,C6,C7
13
Q
What does the musculocutaneous nerve become in the forearm?
A
lateral cutaneous nerve of the forearm
14
Q
What is the biceps reflex?
A
- Deep tendon reflex
- Elicit a flexion jerk
- Tests C5 and C6 spinal segments
- Afferents from muscle spindles – Synapse directly on…
- Efferent Alpha motor neurones
15
Q
What is the biceps reflex?
A
- Deep tendon reflex
- Elicit a flexion jerk
- Tests C5 and C6 spinal segments
- Afferents from muscle spindles – Synapse directly on…
- Efferent Alpha motor neurones
16
Q
What bony attachments can be found on the posterior aspect of the arm?
A
The infraglenoid tubercle
The olecranon
17
Q
What structures are present in the triceps brachii?
A
The long head
The lateral head
The medial head
18
Q
Other than the triceps, what muscles are present on the anterior aspect of the arm?
A
The anconeus
19
Q
What do the triceps brachii do and what nerve roots innervate it?
A
– Extension
• Longhead - stability
– (C6,C7,C8)
20
Q
What does the anconeus do and what nerve roots innervate it?
A
– Elbow stability, tenses joint capsule
• (abduct ulna during pronation)
– (C7,C8,T1)
21
Q
What is the triceps reflex?
A
- Deep tendon reflex
- Elicit an extension jerk
- Tests C6 and C7 spinal segments
- Afferents from muscle spindles – Synapse directly on…
- Efferent Alpha motor neurones
22
Q
What neuromuscular structures of the arm pass into the antebrachium?
A
Ulnar nerve Radial nerve And profunda brachii art. Musculocutaneous nerve (Lateral cutaneous nerve of the forearm) Median nerve and brachial art.
23
Q
Where is the cubital fossa?
A
Area anterior to the elbow
24
Q
What are the borders of the cubital fossa?
A
The line between the lateral and medial epicondyles
The protractor Teres
The brachioradialis
25
What is the roof of the cubital fossa?
The bicipital aponeurosis
26
What are the contents of the cubital fossa?
* From medial → lateral:
* Median nerve
* Brachial Artery
* Biceps tendon
* Radial nerve (Deep and superficial branch)
27
What structures are found on the floor of the cubital fossa?
* Supinator
| * Brachialis
28
What structures are found on the roof of the cubital fossa?
• Biceps
| aponeurosis
29
What structures may be found superficial to the cubital fossa?
• Median
| cubital vein
30
What are the 3 layers of the anterior forearm?
– Superficial, intermediate and deep
31
What are the nerves that supply the muscles of the anterior forearm?
– Median nerve except
| – 1 1⁄2 muscles by the Ulnar nerve
32
Where is the common flexor origin for flexors in the anterior forearm?
medial epicondyle of humerus
33
What muscles are found in the anterior superficial layer of the forearm?
* Pronator teres
* Flexor carpi radialis
* Palmaris longus
* Flexor carpi ulnaris
34
What nerve roots innervate the pronator teres?
• C6,7
35
What nerve roots innervate the flexor carpi radialis?
• C6,7
36
What nerve roots innervate the palmaris longus?
* C7,8
| * Absent ~ 15%
37
What nerve roots innervate the flexor carpi ulnaris?
• Ulnar nerve C7,8
38
What muscles are present in the anterior intermediate layer of the forearm?
* Flexor digitorum Superficialis
| * Middle Pahalnges insertion
39
What nerve roots innervate the flexor digitorum?
• C7,8,t1
40
What muscles are present in the anterior deep layer of the forearm?
* Flexor digitorum profundus
* Flexor policis longus
* Pronator quadratus
41
Where does the flexor digitorum profundus insert?
in the distal phalanges
42
What nerve roots innervate the flexor digitorum profundus?
* Medial 1⁄2 - Ulnar Nerve (C8,T1)
| * Lat. 1⁄2 – Ant. interosseous N. (C8,T1)
43
What nerve roots innervate the flexor policis longus?
• Ant. interosseous N. (C8,T1)
44
What nerve roots innervate the pronator quadratus?
• Ant. interosseous N. (C8,T1)
45
Where is the origin and insertion of the pronator teres?
O - The medial epicondyle
O - Tuberosity of ulna (ulnar head)
I - pronator tuberosity on radius
46
Where is the origin and insertion of the flexor digitorum superficialis?
O - Medial epicondyle of humerus
O - The coronoid process on ulna
O - Anterior oblique line of radius
I - Sides of middle phalanges of digits 2-5
47
Where is the origin and insertion of the flexor digitorum profundus?
O - upper 3/4 of the anterior and medial surfaces of the body of the ulna
I - base of the distal phalanges of the fingers
48
Where is the origin and insertion of the pronator quadratus?
O - Pronator crest on the distal end of the ulna
| I - Distal head of the radius
49
Where is the origin and insertion of the flexor pollicis longus?
O - The middle 1/2 of the anterior surface of the radius
| I - The base of the distal phalanx of the thumb
50
Where is the origin and insertion of the flexor pollicis longus?
O - The middle 1/2 of the anterior surface of the radius
| I - The base of the distal phalanx of the thumb
51
Where is the origin and insertion of the flexor carpi ulnaris?
O - Medial epicondyle
O - Medial margin on olecranon of ulna
I - Pisiform, hook of the hamate, base of the fifth metacarpal bone
52
What are the major arteries of the anterior forearm and their major offshoots?
Brachial artery
Radial artery
Ulnar artery
Perforating branches of anterior interosseous artery
Superficial palmar branch of radial artery
Deep palmar arch
Superficial palmar arch
53
What are the major nerves of the anterior forearm and their major offshoots?
```
Median nerve
Ulnar nerve
Radial nerve
Deep branch of radial nerve
Superficial branch of radial nerve
Anterior interosseous nerve
Dorsal branch of ulnar nerve
Palmar branch of ulnar nerve
Palmar branch of median nerve
```
54
What closes over the carpal tunnel?
Flexor
| retinaculum
55
What are the contents of the carpal tunnel?
* Flexor Digitorum Superficialis
* Flexor Digitorum Profundus
* Flexor Policis Longus
* Median nerve
56
What innervates the muscles of the dorsal forearm?
The radial nerve
57
What are the three groups of the dorsal forearm?
– Superficial, outcropping
| and deep
58
Where is the common extensor origin on the dorsal forearm?
lateral epicondyle of the humerus
59
What is fancy abt the brachioradialis?
• Superficial group but... – Elbow flexor
– 1⁄2 pronator
– 1⁄2 supinator
60
What nerve roots innervate the brachioradialis?
• Radial Nerve – C5,6,7
61
Fraser Chisholm
Bae
62
What is the supinator reflex?
```
• Deep tendon reflex
• Elicit an flexion jerk
• Tests C5 and C6 spinal segments
• Afferents from muscle spindles
– Synapse directly on...
– Efferent Alpha motor neurones
```
63
What are the superficial muscles of the dorsal forearm?
* Extensor carpi radialis longus
* Extensor carpi radialis brevis
* Extensor digitorum
* Extensor digiti minimi
* Extensor carpi ulnaris
64
What nerve roots innervate extensor carpi radialis longus?
– RadialN.C6,7
65
What nerve roots innervate extensor carpi radialis brevis?
– Deep radial N. – C7,8
66
What nerve roots innervate extensor digitorum?
– Deep radial N. – C7,8
67
What nerve roots innervate extensor digiti minimi?
– Deep radial N. – C7,8
68
What nerve roots innervate extensor carpi ulnaris?
– Deep radial N. – C7,8
69
What muscles are found in the outcropping section of the dorsal forearm?
* Abductor policis longus
* Extensor policis brevis
* Extensor policis longus
70
What unusual area is found in the outcropping section of the dorsal forearm?
• Anatomical snuff-box
- Crossed by:
• Cephalic vein
• Dorsal cutaneous branch of radial nerve
- Contains the radial artery
- Its floor is made of the scaphoid and trapezium bones
71
What nerve roots innervate abductor policis longus?
– Post. Interosseous N. C7,8
72
What nerve roots innervate extensor policis brevis?
– Post. Interosseous N. C7,8
73
What nerve roots innervate extensor policis longus?
– Post. Interosseous N. C7,8
74
What muscles are found in the deep section of the dorsal forearm?
* Supinator
| * Extensor indicis
75
What nerve roots innervate the supinator?
– Deep radial N. C7,8
76
What nerve roots innervate the extensor indicis?
– Post. Interosseous N. C7,8
77
What are the origins and insertions of the extensor carpi radialis longus?
O - lateral supracondylar ridge of humerus
| I - 2nd metacarpal
78
What are the origins and insertions of the extensor carpi radialis brevis?
O - lateral epicondyle of humerus
| I - Posterior base of the 3rd metacarpal
79
What are the origins and insertions of the extensor digitorum?
O - lateral epicondyle of humerus
| I - extensor expansion of middle and distal phalanges of the 2nd, 3rd, 4th, and 5th fingers
80
What are the origins and insertions of the extensor digiti minimi?
O - lateral epicondyle of the humerus
| I - the extensor expansion, located at the base of the proximal phalanx of digit V on the dorsal side
81
What are the origins and insertions of the extensor carpi ulnaris?
O - Humeral head: Lateral epicondyle of the Humerus
O - Ulnar head: Olecranon, Posterior surface of ulna
I - 5th metacarpal
82
What are the origins and insertions of the the abductor policis longus?
O - lateral ulna + middle 1/3 of radius
| I - 1st metacarpal
83
What are the origins and insertions of the extensor policis brevis?
O - medial side of bottom 1/3 of radius
| I - thumb on proximal phalanx
84
What are the origins and insertions of the extensor policis longus?
O - Middle third of posterior surface of ulna
| I - thumb on distal phalanx
85
What are the origins and insertions of the supinator?
O - Lateral epicondyle of humerus, supinator crest of ulna
| I - Lateral proximal radial shaft
86
What are the origins and insertions of the extensor indicis?
O - posterior distal third of ulna and interosseous membrane
| I - index finger (2nd digit) (extensor hood)
87
What is a key tendon in the dorsal forearm?
Common extensor tendon
88
What nerves play a key role in sensory supply of the forearm?
```
Median nerve
Ulnar nerve
Radial nerve
Anterior interosseous nerve
Posterior interosseous nerve
Cutaneous nerves
```
