The Cubital Fossa and Forearm Flashcards
1
Q
The Cubital Fossa: junction between the
A
arm (brachium) & forearm regions (antebrachium)
2
Q
Boundaries of the Cubital Fossa:
Lateral
A
brachioradialis muscle
3
Q
Boundaries of the Cubital Fossa:
Medial
A
pronator teres muscle
4
Q
Boundaries of the Cubital Fossa:
Superior
A
an imaginary line between medial & lateral epicondyles of humerus
5
Q
Boundaries of the Cubital Fossa:
Roof (3)
A
skin, superficial & deep fascia, bicipital aponeurosis
6
Q
Boundaries of the Cubital Fossa:
Floor (2)
A
supinator (deep, not shown) and brachialis muscles
7
Q
Contents of the Cubital Fossa (5)
A
- median nerve
- Brachial a. with bifurcation of radial & ulnar arteries
- brachial veins (venae comitantes)
- tendon of biceps brachii & bicipital
aponeurosis - radial nerve
8
Q
radial nerve includes (2)
A
- deep radial nerve
* superficial radial nerve
9
Q
Posterior to the Cubital Region: Elbow Region (4)
A
- triceps and olecranon process
- anconeus
- ulnar nerve runs posterior to medial epicondyle of humerus
- posterior ulnar recurrent artery also runs posterior to medial epicondyle
10
Q
ULNAR SIDE =
A
MEDIAL
11
Q
RADIAL (THUMB) SIDE =
A
LATERAL
12
Q
supinated position is
A
anatomical position
13
Q
pronated (or semipronated) position is
A
how we naturally tend to hold our forearm
14
Q
FOREARM (ANTEBRACHIUM) and HAND: Anterior Compartment (flexor-pronator) = Posterior Compartment (extensor-supinator) =
A
Anterior Compartment (flexor-pronator)
= Ulnar & Median Nerves
Posterior Compartment (extensor-supinator)
= Radial Nerve
15
Q
— — surrounds and invests the forearm and is continuous with the brachial fascia of the arm
A
Antebrachial fascia
16
Q
Cutaneous Nerves of Forearm (3)
A
Musculocutaneous n. (lateral antebrachial cutaneous n.)
Medial antebrachial cutaneous n.
Radial n. (posterior antebrachial cutaneous n.)
17
Q
Blood Supply to Forearm: Cubital Anastomoses Anastomoses between (2)
A
Brachial Artery – Ulnar Artery
Deep Brachial Artery – Radial & Interosseous Arteries
18
Q
Brachial Artery – Ulnar Artery
(2)
A
- Superior ulnar collateral – Posterior ulnar recurrent
* Inferior ulnar collateral – Anterior ulnar recurrent
19
Q
Deep Brachial Artery – Radial & Interosseous Arteries
A
- Radial collateral artery – Radial recurrent artery
* Middle collateral artery – Interosseous recurrent artery
20
Q
Radial and Ulnar arteries: Forearm
Anterior Forearm: (3)
A
- ulnar artery (proper)
- radial artery (proper)
- anterior interosseous a.
21
Q
Palmaris longus:
Proximal Attachment
A
-medial epicondyle of humerus
21
Q
Radial and Ulnar arteries: Forearm Posterior Forearm (4)
A
- radial artery (proper)
- recurrent interosseous a.
- posterior interosseous a.
- Dorsal carpal branch (ulnar a.)
22
Q
Palmaris longus:
Distal Attachment
A
-flexor retinaculum; continuous with palmar aponeurosis
23
Q
Palmaris longus:
Actions (2)
A
flexes hand at wrist,
tenses palmar aponeurosis
24
Palmaris longus:
| Innervation
- median nerve
25
Pronator teres:
| PA
-coronoid process of ulna
26
Pronator teres:
| DA
-middle of lateral surface of radius
27
Pronator teres:
| Actions (2)
-pronates and flexes forearm at elbow
28
Pronator teres:
| Inn
- median nerve
29
Flexor carpi radialis:
| PA
medial epicondyle of humerus
| “common flexor origin”
30
Flexor carpi radialis:
| DA
-base of 2nd metacarpal
31
Flexor carpi radialis:
| Actions (2)
-flexes and abducts hand at wrist
32
Flexor carpi radialis:
| Inn
- median nerve
33
Flexor carpi ulnaris:
| PA (2)
- medial epicondyle of humerus (humeral head)
| - Olecranon & posterior border of ulna (ulnar head)
34
Flexor carpi ulnaris:
| DA (3)
pisiform,
hook of hamate,
5th metacarpal
35
Flexor carpi ulnaris:
| Actions (2)
-flexes and adducts hand at wrist
36
Flexor carpi ulnaris:
| Inn
- ulnar nerve
37
Flexor digitorum superficialis:
| PA (2)
- medial epicondyle of humerus,
| - superior ½ of anterior border of radius
38
Flexor digitorum superficialis:
| DA
-shafts of middle phalanges of medial 4 digits
39
Flexor digitorum superficialis:
| Actions (2)
-flexes middle phalanges at proximal
interphalangeal joint,
-flexes proximal phalanges at metacarpophalangeal joints
40
Flexor digitorum superficialis:
| Inn
-median nerve
41
Flexor digitorum profundus:
| PA (2)
-proximal ¾ of medial and anterior surfaces of ulna and interosseous
membrane
42
Flexor digitorum profundus:
| DA
-bases of distal phalanges of 2nd-5th fingers
43
Flexor digitorum profundus:
| Actions
-flexes distal phalanges at interphalangeal joints (power grip)
44
Flexor digitorum profundus:
| Inn (2)
- median*
* anterior interosseus nerve branch from median nerve
- ulnar nerves
45
Flexor pollicis longus:
| PA (2)
- anterior surface of radius
| - interosseous membrane
46
Flexor pollicis longus:
| DA
-base of distal phalanx of thumb
47
Flexor pollicis longus:
| Actions
-flexes thumb
48
Flexor pollicis longus:
| Inn
median nerve via anterior interosseous nerve (C8, T1)
49
Pronator quadratus:
| PA
-distal ¼ of anterior surface of ulna
50
Pronator quadratus:
| DA
-distal ¼ of anterior surface of radius
51
Pronator quadratus:
| Actions (3)
- pronates forearm,
- deep fibers bind radius,
- ulna together
52
Pronator quadratus:
| Inn
median nerve via anterior interosseous
| nerve
53
Superficial Extensors: most attach t the
lateral epicondyle of the humerus
54
Superficial Extensors include (6)
* brachioradialis (flexes elbow joint)
* extensor carpi radialis longus
* extensor carpi radialis brevis
* extensor digitorum
* extensor digiti minimi
* extensor carpi ulnaris
55
brachioradialis is in the posterior --- compartment but actually functions to flex the --- joint
forearm
| elbow
56
ALL muscles of the posterior forearm are innervated by the --- nerve via the (2)
radial
| deep branch of the radial nerve or the posterior interosseous nerve
57
Innervation of Posterior Forearm
```
• Radial Nerve
• superficial branch of radial nerve
(lateral, runs beneath brachioradialis)
CUTANEOUS ONLY (no motor branches)
• deep branch of radial nerve
(posterior, becomes posterior interosseous
nerve)
```
58
Innervation of Posterior Forearm:
| The deep branch of the radial nerve continues as the
posterior interosseous nerve
59
Brachioradialis:
| PA
-proximal 2/3 of supraepicondylar ridge of humerus
60
Brachioradialis:
| DA
-distal radius, proximal to styloid process
61
Brachioradialis:
| Actions
-flexes forearm when it is pronated (about midprone position)
62
Brachioradialis:
| Inn
radial nerve
63
Extensor carpi radialis longus:
| PA
-lateral supracondylar ridge of humerus
64
Extensor carpi radialis longus:
| DA
-dorsal aspect of base of 2nd metacarpal
65
Extensor carpi radialis longus:
| Actions
-extend and abduct hand at wrist
66
Extensor carpi radialis longus:
| Inn
-radial nerve
67
Extensor carpi radialis brevis:
| PA
lateral epicondyle of humerus (common extensor origin)
68
Extensor carpi radialis brevis:
| DA
-dorsal aspect of base of 3rd metacarpal
69
Extensor carpi radialis brevis:
| Actions
-deep branch of radial nerve
70
Extensor carpi radialis brevis:
| Inn
-extend and abduct hand at wrist
71
Extensor carpi ulnaris:
| PA (2)
- lateral epicondyle of humerus
| - posterior border of ulna
72
Extensor carpi ulnaris:
| DA
-dorsal aspect of base fo 5th metacarpal
73
Extensor carpi ulnaris:
| Actions (2)
-extends and adducts hand at wrist
74
Extensor carpi ulnaris:
| Inn
-posterior interosseous nerve
75
posterior interosseous nerve is continuous with
deep branch of the radial nerve
76
Extensor digitorum:
| PA
-lateral epicondyle of humerus
| common extensor origin
77
Extensor digitorum:
| DA
-extensor expansions of medial 4 fingers
78
Extensor digitorum:
| Actions
-extends medial 4 fingers at metacarpophalangeal joints and somewhat at interphalangeal joints
79
Extensor digitorum:
| Inn
-posterior interosseous nerve
80
The tendons of extensor digitorum form a dorsal expansion over the metacarpophalangeal (MP) and interphalangeal (IP) joints called the (2)
extensor expansion and extensor hood
81
As --- --- ----, it pulls on the extensor expansion (extensor hood), which
causes the interphalangeal (IP) joints to extend
extensor digitorum contracts
82
The --- also attach to this expansion at the “hood” and are thus also able to extend the IP joints
lumbricals
83
Extensor digiti minimi:
| PA
-lateral epicondyle of humerus
| common extensor origin
84
Extensor digiti minimi:
| DA
-extensor expansion of 5th finger
85
Extensor digiti minimi:
| Actions (2)
-extends 5th finger at metacarpophalangeal joint
| and secondarily at interphalangeal joints
86
Extensor digiti minimi:
| Inn
-posterior interosseous nerve
87
Deep Extensors includes (5)
* supinator
* extensor indicis
* abductor pollicis longus
* extensor pollicis longus
* extensor pollicis brevis
88
"outcropping muscles" (3)
* abductor pollicis longus
* extensor pollicis longus
* extensor pollicis brevis
89
ALL deep extensors are innervated by the (2), which is the continuation of this same nerve
deep branch of the radial nerve, or the posterior interosseus nerve
90
Supinator:
| PA (3)
- lateral epicondyle of humerus,
- radial collateral & anular ligaments,
- ulnar crest
91
Supinator:
| DA
-proximal 1/3 of radius (nearly all surfaces, as it wraps around the bone)
92
Supinator:
| Actions
-supinates forearm, bringing radius back to anatomical position
93
Supinator:
| Inn
-deep branch of radial nerve
94
Extensor indicis:
| PA (2)
-posterior surface of distal 1/3 of ulna and interosseous membrane
95
Extensor indicis:
| DA
-extensor expansion of 2nd finger
96
Extensor indicis:
| Actions (2)
- independent extension of 2nd finger,
| - but also helps with extension of wrist
97
Extensor indicis:
| Inn
-posterior interosseous nerve
98
Abductor pollicis longus:
| PA (2)
- posterior surface of proximal ½ of ulna and radius,
| - interosseous membrane
99
Abductor pollicis longus:
| DA
-base of 1st metacarpal
100
Abductor pollicis longus:
| Actions (2)
-abducts thumb and extends it at carpometacarpal joint
101
Abductor pollicis longus:
| Inn
-posterior interosseous nerve
102
Extensor pollicis brevis:
| PA (2)
- posterior surface of distal 1/3 of radius,
| - interosseous membrane
103
Extensor pollicis brevis:
| DA
-dorsal aspect of proximal phalanx of thumb
104
Extensor pollicis brevis:
| Actions (2)
-extends proximal phalanx of thumb at its
metacarpophalangeal joint,
-extends carpometacarpal joint
105
Extensor pollicis brevis:
| Inn
-posterior interosseous nerve
106
Extensor pollicis longus:
| PA (2)
- posterior surface of middle 1/3 of ulna,
| - interosseous membrane
107
Extensor pollicis longus:
| DA
-dorsal aspect of base of distal phalanx of thumb
108
Extensor pollicis longus:
| Actions (2)
- extends distal phalanx of thumb at its interphalangeal joint
- extends the metacarpophalangeal and carpometacarpal joint
109
Extensor pollicis longus:
| Inn
-posterior interosseous nerve
110
Anatomical Relationships
| From lateral to medial (5)
* Superficial branch of the Radial nerve
* Radial artery
* Median Nerve
* Ulnar Artery
* Ulnar Nerve
111
Ulnar Nerve Relationships (4)
• Posterior to the medial epicondyle
• Runs along the medial forearm under the flexor carpi ulnaris
• Goes through Guyon’s canal lateral to the pisiform bone (this is a
fascial compartment)
• Enters the hand and supplies most of the intrinsic muscles of the hand
112
Anatomical Relationships
• Ulnar nerve and ulnar artery:
• ulnar artery and flexor carpi ulnaris:
• ulnar artery and nerve to pisiform bone and Guyon’s canal:
• Ulnar nerve and ulnar artery: Run together , nerve is medial
• ulnar artery and flexor carpi ulnaris: Located under flexor carpi ulnaris or
just lateral to it
• ulnar artery and nerve to pisiform bone and Guyon’s canal: lateral
113
Median Nerve Relationships
Median nerve to pronator teres:
Median nerve to flexor digitorum superficialis:
Median nerve to flexor retinaculum:
Median nerve to pronator teres:
-runs through it
Median nerve to flexor digitorum superficialis:
-deep to it (runs between F.d. superficialis and F.d.profundus)
Median nerve to flexor retinaculum:
-deep to it (through carpal tunnel)
114
* ulnar artery and flexor carpi ulnaris:
* ulnar artery and ULNAR nerve to pisiform bone and Guyon’s canal:
* radial artery to the superficial branch of the radial nerve:
* radial artery to brachioradialis:
* ulnar artery and flexor carpi ulnaris: Located under flexor carpi ulnaris or just lateral to it
* ulnar artery and ULNAR nerve to pisiform bone and Guyon’s canal: lateral
* radial artery to the superficial branch of the radial nerve: Artery is medial (nerve lateral)
* radial artery to brachioradialis: Under brachioradialis or just medial to it
115
Anterior interosseous nerve & anterior interosseous artery to the pronator quadratus muscle:
The nerve and artery run deep (posterior) to the muscle
