Muscles of the Hand Flashcards Preview

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Flashcards in Muscles of the Hand Deck (45):
1

What are the two groups of muscles that act on the hand?

Intrinsic
Extrinsic

2

Where are the extrinsic muscles mainly found?

In the forearm

3

What do the extrinsic muscles do?

Offer the forceful grip of the hand

4

Where are the intrinsic muscles found?

Inside the hand

5

What do the intrinsic muscles do?

The finer movements of the hand eg writing

6

What are the muscles of the hand?

Adductor pollicis
Interossei
Thenar
Palmaris brevis
Lumbricals
Hyperthenar muscles

7

Which muscles are responsible for the fine movement of the thumb?

The thenar muscles
Adductor pollicis

8

Which nerve innervates the thenar muscles?

The median nerve

9

What are the 3 thenar muscles?

Oppenens pollicis
Abductor pollicis brevis
Flexor pollicis brevis

10

Which is the largest of the thenar muscles?

Oppenens pollicis. It lies under the other two thenar muscles

11

What is the main action of the oppoenens pollicis?

Opposes the thumb by medially rotating and flexing the metacarpel on the trapezium

12

Where is the abductor pollicis brevis found?

Anteriorly to the oppoenens pollicis
Proximal to flexor pollicis brevis

13

What is the main action of the abductor pollicis brevis?

Abducts the thumb

14

What is the main action of the flexor pollicis brevis?

Flexes the metacarpel-phalangeal joint of the thumb.

15

What are the hypothenar muscles?

Opponens digiti minimi
Abductor digiti minimi
Flexor digiti minimi brevis

16

Where are the hypothenar muscles located?

At the base of the little finger
Medial side of the palm

17

What nerve innervates the hypothenar muscles?

The ulnar nerve

18

Where is the opponens digiti minimi?

Deep to the hypothenar muscles

19

What is the main action of the opponens digiti minimi?

Produces opposition by rotating the metacarpel of the little finger towards the palm

20

Where is the Abductor digiti minimi?

Superificial to the hypothenar muscles

21

What is the main action of Abductor digiti minimi?

Abducts the little finger

22

Where is the flexor digiti minimi brevis?

Lateral to the abductor digiti minimi

23

What is the main action of the flexor digiti minimi brevis?

Flexes the metacarpel-phalangeal joint of the little finger

24

What are the two muscles of the palm which do not fit into the hypothenar group or thenar group?

Adductor pollicis
Palmaris brevis

25

What is special about the Adductor pollicis?

It has two heads with the radial artery passing through them to form the deep palmar arch

26

What is the main action of the Adductor pollicis?

Adduction of the thumb

27

What nerve innervates the Adductor pollicis?

The ulnar nerve

28

Where is the palmaris brevis?

Superficial to the subsutaneous tissue of the hypothenar eminence

29

What is the main action of the palmaris brevis?

Deepens the curvature of the hand to improve grip

30

What nerve innervates the palmaris brevis?

The ulnar nerve

31

How many lumbrical muscles are there?

Four. One associated with each finger.

32

Why are the lumbricals essential for finger movement?

They link the extensor tendons with the flexor tendons

33

What happens with denerveration of the lumbricals?

Ulnar claw
Hand of Benediction

34

What is the main action of the lumbricals?

Flex at the metacarpal-phalangeal joint of the finger
Extend at the inter-phalangeal joint of the finger

35

What innervates the lumbricals?

Medial 2 lumbricals = Ulnar nerve
Lateral 2 lumbricals = Median nerve

36

Where are the interossei muscles?

Between the metacarpals

37

What are the two types of interossei?

Dorsal interossei
Palmar interossei

38

How many dorsal interossei are there?

Four

39

Where are the dorsal interossei located?

Superficially

40

What is the main action of the dorsal interossei?

Abduct the fingers at the metacarpal-phalangeal joint

41

What innervates the dorsal interossei?

The ulnar nerve

42

Where are the Palmar interossei located?

Anteriorly on the hand

43

How many palmar interossei are there?

Three

44

What is the main action of the palmar interossei?

Adducts the finger at the metacapal-phalangeal joint

45

What innervates the palmar interossei muscles?

The ulnar nerve