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Flashcards in The anatomy of the hand Deck (68)
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1
Q

Where do all fingers point when they’re flexed?

A

Scaphoid tubercle

2
Q

What do ligaments in the hand do?

A

Join bones to other bones

3
Q

Characteristics of ligaments in hands

A

Co-axial or co-lateral

4
Q

Features of hand

A
  • Creases
  • Thenar/hypothenar eminence
  • Hills and valleys
  • Web spaces
  • Sesamoids
  • Lister’s tubercle - extensor polices longus
  • DIP - distal interphalangeal joint
  • PIP - proximal interphalangeal joint
  • MCP - metacarpophalangeal joint
5
Q

How many bones are in the hand?

A

31

6
Q

Where are the 31 bones in the hand?

A
  • Phalanges: 14
  • Sesamoids: 2
  • Metacarpals: 5
  • Carpals (proximal row): 4
  • Carpals (distal row): 4
  • Radius
  • Ulna
7
Q

What are the 8 bones in the hand?

A
  • Scaphoid
  • Lunate
  • Triquetrum
  • Pisiform
  • Trapezium
  • Trapezoid
  • Capitate
  • Hamate
8
Q

How do you assess the hand?

A

To assess the hand, palpate for swelling/tenderness. The following areas should be palpated:
- Radial styloid
- Scaphoid
- 1st MC/trapezium joint
- Lunate
- Lister’s tubercle
Then assess for symmetry and look for any visible fractures and any phalangeal rotation. Normally, everything in the hand should form a line from fingertip to wrist

9
Q

What does FOOSH stand for?

A

Fall on outstretched hand

10
Q

Symptoms of FOOSH injury

A
  • Tender snuffbox
  • Painful/swollen wrist
  • High frequency of non-union and avascular necrosis
11
Q

Which parts of the hand can be palpated on the central and ulnar sides?

A
  • Metacarpals
  • Ulnar styloid
  • Triquetrum
  • Pisiform
  • Hook of hamate
12
Q

Characteristics of injured pisiform/hamate

A
  • Frequently misdiagnosed as tendonitis/spasm
  • Pain/swelling over hypothenar eminence
  • Painful gripping and swinging
13
Q

Range of wrist motion

A
  • Flexion (make fist)
  • Extension (extend fingertips)
  • Radial deviation
  • Ulnar deviation (typically greater than radial deviation)
14
Q

Range of finger motion:

A
  • Flexion/extension at MCP, PIP, DIP
  • Tight wrist and open to test grip
  • Abduction/adduction at MCP (spread fingers apart then back together)
15
Q

Where are proximal phalanges frequently injured?

A

Shaft/base

16
Q

When are metacarpals frequently injured?

A

Boxing

17
Q

What are intrinsic hand muscles?

A

Start in metacarpals and finish at fingertips

18
Q

What are extrinsic hand muscles?

A

Start in wrists and finish at fingertips

19
Q

How many extensor muscles are there?

A

12

20
Q

How many flexor muscles are there?

A

8

21
Q

How many intrinsics are there?

A

2 sets of 4

22
Q

Which nerve supplies extensor muscles?

A

Radial nerve

23
Q

What is the common extensor origin?

A

Lateral epicondyle

24
Q

Which condition affects the common extensor origin?

A

Tennis elbow

25
Q

What are the 12 extensor muscles?

A
  • Brachioradialis - from brachium to radius
  • Extensor carpi radialis longus
  • Extensor carpus radius brevis
  • Abductor pollicis longus
  • Extensor pollicis brevis
  • Extensor pollicis longus
  • Extensor indices proprius
  • Extensor digitorum communis
  • Extensor digitorum minimi
  • Supinator
  • Anconeus
  • Extensor carpi ulnaris
26
Q

What are the two types of flexors?

A

Superficialis and deepus

27
Q

Which nerves supply the flexor muscles?

A

Median and ulnar

28
Q

Which arteries supply the flexor muscles?

A

Radial and ulnar

29
Q

Which joint do the superficial flexor muscles bend?

A

The PIP joint

30
Q

Which joint do the deep flexor muscles bend?

A

DIP joint

31
Q

What is the common flexor origin?

A

Medial epicondyle

32
Q

Which condition affects the common flexor origin?

A

Golfer’s elbow

33
Q

Are the 8 flexor muscles posterior or anterior?

A

Anterior

34
Q

What is the name of the vessel that transports nerves/arteries/flexor tendons into the hand?

A

Palmar tunnels

35
Q

How many palmar tunnels are there?

A

2

36
Q

What are the 8 flexor muscles?

A
  • Flexor digitorum superficialis (middle finger)
  • Flexor digitorum profundus
  • Palmaris longus
  • Flexor pollicis longus (thumb)
  • Flexor carpi radialis (index fingers)
  • Flexor carpi ulnaris
  • Pronator teres (in thumb)
  • Pronator quadratus
37
Q

How to test the FDS?

A

Flex the finger at the PIP joint - FDS is the only tendon functioning here

38
Q

How to test the FDP?

A

Flex the DIP joint - FDP is the only tendon functioning here

39
Q

Function of transport extensor tendons?

A

Reduce bowstringing in transition from forearm into hand

40
Q

How many compartments does the extensor retinaculum form?

A

6

41
Q

Why are tendons bathed in synovial fluid?

A

Blood flow

42
Q

What are vinaculae?

A

Blood vessels supplying tendons

43
Q

What are palmar spaces involved in?

A

Infection

44
Q

Which two spaces are known for collecting bacteria and pus?

A

Thenar and midpalmar

45
Q

What is the palmar aponeurosis?

A

A sheet of tissue under the skin of the palm that helps to form ridges

46
Q

What 4 deep spaces are involved in hand infections?

A

Subfascial palmar
Dorsal subaponeurotic
Thenar
Midpalmar

47
Q

What are the two eminences in the finger?

A

Thenar and hypothenar

48
Q

Characteristics of the thenar eminence

A

3 muscles of the thumb, atrophy seen in carpal tunnel syndrome median nerve

49
Q

Characteristics of hypothenar eminence

A

3 muscles of little finger, atrophy with ulnar nerve compression

50
Q

What are the three muscles found in an eminence?

A

Opponens (helps thumb oppose)
Abductor (lift away from palm)
Flexor (flex thumb down)

51
Q

What is Dupuytren’s contracture?

A

Contracture under skin but above tendons

52
Q

Which tunnel holds the median nerve?

A

Carpal tunnel

53
Q

Which vessel holds the ulnar nerve and artery?

A

Guyon’s canal

54
Q

Test for radial nerve

A

Thumb up/ little and index fingers up

55
Q

Test for ulnar nerve

A

Cross fingers

56
Q

Test for median nerve

A

Okay sign

57
Q

What happens when ulnar nerve is damaged?

A

Flattening of hypothenar eminence and loss of intrinsics (can’t PAD or DAB)

58
Q

What does DAB stand for?

A

Dorsal abducts

59
Q

What does PAD stand for?

A

Palm adducts

60
Q

Where are interossei found?

A

Between metacarpals, there are two layers (one on dorsal and one on palmar side)

61
Q

Which nerve causes adduction and abduction of fingers?

A

Ulnar nerve

62
Q

What connects flexors to fingers?

A

Flexor retinaculum

63
Q

Characteristics of carpal tunnel

A

U-shaped bones with lid, joining scaphoid/pisiform/hamate

64
Q

Opposition of thumb

A

Touch tip to tip of each finger

65
Q

Flexion of thumb

A

Moves towards palm

66
Q

Extension of thumb

A

Away from palm

67
Q

Where does most movement in the digits occur?

A

Carpometacarpal joint

68
Q

Where does flexion/extension of the thumb occur?

A

MCP and IP