Wrist and Hand Anatomy Flashcards Preview

KNES 360 Exam 3 > Wrist and Hand Anatomy > Flashcards

Flashcards in Wrist and Hand Anatomy Deck (59):
1

Wrist and Hand Anatomy: Bones

Radius: larger of two bones
Ulna
8 Carpal Bones
5 Metacarpals: number 1-5 (thumb is 1)
14 Phalanges: 3 per finger, 2 for thumb

2

Carpal Bones Names

Scaphoid
Lunate
Triquetrum
Pisiform
Trapzium
Trapezoid
Capitate
Hamate

3

Carpal Bones

Concave on palmar side
Bony arch is spanned by transverse carpal and vulgar ligaments
Creates carpal tunnel
Median nerve and all flexor tendons except flexor carpi ulnas and palmaris longs pass through carpal tunnel
-flexor digitorum profundus(4)
-flexor digitorum superficialis (4)
-flexor pollicis longus
-median nerve

4

Landmarks Humerus

Supracondylar ridge
Medial epicondyle
Lateral epicondyle

5

Landmarks Radius

Radial styloid process
Radial head
Radial tuberosity

6

Landmarks Ulna

Ulnar styloid process
Olecranon process
Coronoid process

7

Landmarks Hand

Transverse carpal ligament: carpal tunnel
Hook of hamate
Tunnel of guyon: ulnar nerve

8

Carpal tunnel borders

radial- scaphoid and trapezium
ulnar: pisiform and hook of hamate
top: flexor retinaculum

9

Carpal tunnel contents:

flexor digitorum profundus (4 tendons)
flexor digitorum superficialis (four tendons)
flexor pollicis longus
median nerve

10

Snuffbox

Extensor pollicis longus (medial side)
Extensor pollicis brevis (lateral side)
Extensor pollicis longus (lateral side)

11

Brachioradialis

O: supracondylar ridge of humerus
I: styloid process of radius
A: elbow flexion; pronation from supinated position to neutral; supination from pointed position to neutral
IN: Radial nerve

12

Superficial flexor/pronators

Pronator teres
flexor carpi radialis
palmaris longus
flexor carpi ulnaris

13

Pronator Teres

O: Humeral head: Medial epicondylar ridge and common flexor tendon
Ulnar head: coronoid process of ulna
I: Middle of lateral surface of radius
A: forearm pronation; assists in elbow flexion
IN: median nerve

14

Flexor Carpi Radialis

O: Medial epicondyle of humerus
I: Base of 2nd/3rd metacarpal bones
A: Wrist flexion, radial deviation, assists in elbow flexion
IN: Median nerve

15

Palmaris Longus

O: Medial epicondyle of humerus
I: transverse carpal ligament and palmar aponeurosis
A: Wrist flexion and assists in elbow flexion
IN: median nerve

16

Flexor Carpi Ulnaris

O: Humeral head- medial condyle of humerus
Ulnar head- olecranon
I: pisiform, hamate, and 5th metacarpal
A: wrist flexion, ulnar deviation, assist in elbow flexion
IN: Ulnar Nerve

17

Deep flexor/pronator muscles

flexor digitorum superficialis
flexor digitorum profundus
flexor pollicis longus
pronator quadratus

18

Flexor Digitorum Superficialis

O: Humeral head: medial epicondyle of humerus
Ulnar head: coronoid process
Radial head: Oblique line of radius
I: Palmar surface of middle phalanx of medial 4 digits
A: Flex middle phalanges (PIP) of medial 4 digits, aids in wrist and forearm flexion
IN: Median nerve

19

Flexor Digitorum Profundus

O: Medial and anterior surface of ulna and interosseous membrane
I: base of distal phalanges of medial 4 digits
A: MCP, PIP, DIP flexion; wrist flexion
IN: Median nerve (2-3 digit), Ulnar nerve (4-5th digit)

20

Flexor Pollicis Longus

O: Anterior surface of radius and interosseous membrane; coronoid process of ulna
I: base of distal phalanx of the thumb
A: thumb CMC, MCP, IP joint flexion; wrist flexion
IN: median nerve

21

Pronator Quadratus

O: distal 1/4 of the anterior surface of ulna
I: distal 1/4 of the anterior surface of radius
A: Forearm pronation
IN: median nerve

22

Superficial extensor/supinators

Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor digitorum
Extensor carpi ulnaris

23

Extensor Carpi Radialis Longus

O: Lateral supracondylar ridge; lateral epicondyle
I: dorsal surface of base and 2nd metacarpal
A: wrist extension, radial deviation, assists with elbow extension
IN: Radial nerve

24

Extensor Carpi Radialis Brevis

O: lateral epicondyle of humerus
I: dorsal surface of base of 3rd metacarpal
A: wrist extension, radial deviation, assist with elbow extension
IN: Radial nerve

25

Extensor Digitorum

O: Lateral epicondyle of humerus
I: bases of middle and distal phalanges of medial 4 digits
A; MCP extension of medial 4 digits, assists with wrist and elbow extension
IN: Radial nerve

26

Extensor Carpi Ulnaris

O: Lateral epicondyle of humerus
I: Medial side of base of 5th metacarpal
A: Wrist extension, ulnar deviation, assist with elbow extension
IN: Radial nerve

27

Deep extensor/supinators

Supinator
Abductor Pollicis Longus
Extensor Pollicis Longus
Extensor Pollicis Brevis
Extensor Indicis

28

Supinator

O: Lateral epicondyle of the humerus; lateral proximal ulna
I: lateral surface of radius
A: forearm supination
IN: radial nerve

29

Abductor Pollicis Longus

A: thumb and wrist abduction
IN: radial nerve

30

Extensor Pollicis Brevis

A: Extension of proximal phalanx thumb
IN: Radial nerve

31

Extensor Pollicis Longus

A: Extension of distal phalanx of thumb
IN: Radial nerve

32

Radial Nerve

Brachioradialis
Ext. Carpi Radialis Longus
Ext. Carpi Radialis Brevis
Ext. Digitorum
Ext. Digiti Minimi
Ext. Carpi Ulnaris
Supinator
Ext. Indicis

33

Median Nerve

Pronator Teres
Flexor Carpi Radialis
Palmaris Longus
Flexor Digitorum Superficialis
Flexor Pollicis Longus
Pronator Quadratus

34

Ulnar Nerve

Flexor Carpi Ulnaris
Flexor Digitorum Profundus
Flexor Pollicis Longus

35

Thenar eminence Muscles

Abductor pollicis brevis
Flexor pollicis brevis
Opponens pollici
Adductor pollicis

36

Abductor Pollicis Brevis

A: Thumb abduction (at CMC)
IN: Median nerve

37

Opponens Pollicis

A: Thumb opposition (at CMC)
IN: Median nerve

38

Flexor Pollicis Brevis

A: Flexes proximal phalanx of thumb
IN: Median nerve

39

Adductor Pollicis

A: thumb adduction (at CMC)
IN: ulnar nerve

40

Hypothenar Eminence Muscles

Abductor Digiti Minimi
Flexor Digiti Minimi Brevis
Opponens Digiti Minimi

41

Abductor Digiti Minimi

A: Abduction of the 5th digit from the 4th digit
IN: Ulnar nerve

42

Opponens Digiti Minimi

A: opposition of the 5th digit
IN: Ulnar nerve

43

Flexor Digiti Minimi

A: flexion of proximal phalanx of the 5th digit
IN: Ulnar nerve

44

Palmar muscles

Lumbricals
Palmar interossei
Dorsal itrossei

45

Palmar Muscle: Lumbricals Action

MCP flexion of medial 4 digits and PIP/DIP extension of medial 4 digits

46

Palmar Muscle: Palmar Interossei Action

MCP adduction of 2nd, 4th and 5th digits

47

Palmar Muscle: Dorsal Introssei

MCP flexion
MCP abduction
PIP/DIP extension of 2, 3, 4th digits

48

Median Nerve

Abductor Pollicis Brevis
Opponens Pollicis
Flexor Pollicis Brevis
Lumbricales (2 lateral)

49

Ulnar Nerve

Abductor Digiti Minimi
Opponens Digiti Minimi
Flexor Digiti Minimi
Adductor Pollicis Lumbricales (2 medial)
Dorsal Interossei
Palmar Interossei

50

Radial Nerve

Abductor Pollicis Longus
Extensor Pollicis Brevis
Extensor Pollicis Longus

51

Scaphoid Fracture

Most common carpal fracture
Pain in anatomical snuff box

52

Forearm Fractures

Epidemiology: highest ratio of open to closed than any other fracture except the tibia
More common in males than females (contact sports, altercations, falls

53

Carpal Tunnel Syndrome

Most common compression neuropathy of the wrist
-Compression of the median nerve as it passes through the carpal tunnel
Any sports related activity that involves repetitive wrist motion may be the cause
Fine, coordinated movements may become difficult due to a loss in proprioception
Signs and symptoms of this compression injury are relieved by the division of the flexor retinaculum, "tunnel release"

54

Carpal Tunnel Syndrome Symptoms

Movements of fingers unaffected, thumb movements not seriously impaired
Flexion accomplished by flexor pollicis longus (ant. interosseous nerve) and by deep head of the flexor pollicis braves (ulnar nerve)
Opponens pollici action lost, OPP is attained by flexors, ABD provided by abductor pollicis longus (radial nerve)

55

Radial Nerve Injury

Compression: Transient paralysis
Humeral fracture: surgical neck or shaft, skin sensitively testing may not represent injury, elbow extension may still be obtained, test with arm ABD, wrist extensors may be paralyzed "wrist drop"

56

Radial Nerve Injury Lesions

Different paralysis patterns
"wrist drop" paralysis of extensor arm muscles, if lesion exists in nerve after it pierces the lateral inter muscular septum
Complete deep branch lesions may cause inability to extend MCP joints, radial extensors can still extend wrist
Surgical repair is difficult

57

Ulnar Nerve Injury- Damage at Wrist

Flexor digitorum profundus unaffected
Hypothenar, interossei, ulnar two lumbricals, ADD pollicis become paralyzed
MCP joint become hyperEXT, due to overall of ext. digitorum
FLEX of IP joints, due to overall of flexor digitorum profundus

Muscle imbalance at the thumb results in ABD
The transverse MC arch becomes flat, "ulnar claw hand"
Sensation lost in area distal to lesion, skin dry, and vasodilated

58

Ulnar Nerve Injury- Damage at Elbow

Less severe than wrist (unlike median nerve)
Vulnerable behind medial epicondyle
May become loose and dislocate from groove
Results in possible neuritis, paralysis
Supply to hand may be affected before flexor carpi ulnas and flexor digitorum muscles
When nerve supply to flexor digitorum is lost, muscle imbalance in the ulnar two fingers improves and the degree of "clawing" is reduced

59

Volkmann's Contracture

Degeneration, contracture, fibrosis, and atrophy of muscles
Results from injury to blood and nerve supply
-Brachial artery and median nerve
Usually seen in the hand