Muscles Of The Hand

Question 1

What is the difference between the extrinsic and intrinsic muscles of the hand?

Answer 1

Extrinsic- located in the anterior and posterior compartments of the forearm, they control crude movements and produce a forceful grip

Intrinsic- located within the hand itself, they are responsible for the fine motor functions of the hand

Question 2

How many intrinsic muscles of the hand are there? Name them

Answer 2

6:
Adductor pollicis 
Palmaris Blevins
Interossei
Lumbricals
Thenar 
Hypothenar

Question 3

What nerve innervates the thenar muscles?

Answer 3

Median

Question 4

How many muscles make up the thenar eminance, name them?

Answer 4

3:
Opponens pollicis
Abductor pollicis Brevis
Flexor pollicis Brevis

Question 5

Where does the opponens pollicis lie in relation to the other thenar muscles in the hand?

Answer 5

Largest and lies underneath them

Question 6

What are the attachments of the opponens pollicis, one of the thenar muscles in the hand?

Answer 6

Originates from the tubercle of the trapezium and associated flexor retinaculum

Inserts into the lateral margin of the metacarpal of the thumb

Question 7

What is the action of the opponens pollicis, one of the thenar muscles in the hand?

Answer 7

Opposed the thumb, by medially rotating and flexing the metacarpal on the trapezium

Question 8

What nerve innervates the opponens pollicis, one of the thenar muscles in the hand?

Answer 8

Median nerve

Question 9

In relation to the other thenar muscles of the hand, where is the abductor pollicis Brevis ?

Answer 9

Found anteriorly to the opponens pollicis and proximal to the flexor pollicis brevis

Question 10

What are the attachments of the abductor pollicis brevis, one of the thenar muscles in the hand?

Answer 10

Originates from the tubercles of the scaphoid and trapezium and from the associated flexor retinaculum

Attaches to the lateral side of proximal phalanx of the thumb

Question 11

What is the action of the abductor pollicis brevis, one of the thenar muscles in the hand?

Answer 11

Abducts the thumb

Question 12

What nerve innervates the abductor pollicis brevis, one of the thenar muscles in the hand?

Answer 12

Median

Question 13

Where is the flexor pollicis brevis muscle in relation to the other thenar muscles of the hand?

Answer 13

Most distal of the muscles

Question 14

What are the attachments of the flexor pollicis brevis, one of the thenar muscles in the hand?

Answer 14

Originates from the tubercle of the trapezium and from the associated flexor retinaculum

Attaches to the base of the proximal phalanx of the thumb

Question 15

What is the action of the flexor pollicis brevis, one of the thenar muscles in the hand?

Answer 15

Flexes the metacarpophalangeal (MCP) join of the thumb

Question 16

What nerve innervates the flexor pollicis brevis, one of the thenar muscles in the hand?

Answer 16

Median

Question 17

How many muscles make up the hypothenar eminence? Name them

Answer 17

3:
Opponens digiti minimi,
Abductor digiti minimi and flexor digiti minimi brevis

Question 18

In relation to the other hypothenar muscles, where is the opponens digiti minimi muscle of the hypothenar eminence in the hand?

Answer 18

Lies deep to the others

Question 19

What are the attachments of the opponens digiti minimi muscle of the hypothenar eminence in the hand?

Answer 19

Originates from the hook of hamate and associated flexor retinaculum

Inserts into the medial margin of metacarpal V

Question 20

What is the action of the opponens digiti minimi muscle of the hypothenar eminence in the hand?

Answer 20

Rotaries the metacarpal of the little finger towards the palm, producing opposition

Question 21

What nerve innervates the opponens digiti minimi muscle of the hypothenar eminence in the hand?

Answer 21

Ulnar

Question 22

In relation to the other muscles of the hypothenar, where is the abductor digiti minimi muscle of the hypothenar eminence in the hand?

Answer 22

Most superficial muscle

Question 23

What are the attachments of the abductor digiti minimi muscle of the hypothenar eminence in the hand?

Answer 23

Originates from the pisiform and the tendon of the flexor carpi ulnaris

Attaches to the base of the proximal phalanx of the little finger

Question 24

What is the action of the abductor digiti minimi muscle of the hypothenar eminence in the hand?

Answer 24

Abducts the little finger

Question 25

What nerve innervates the abductor digiti minimi muscle of the hypothenar eminence in the hand?

Answer 25

Ulnar

Question 26

In relation to the other. Hypothenar muscles, where is the flexor digiti minimi brevis muscle of the hypothenar eminence in the hand?

Answer 26

Lies laterally to the abductor digiti minimi

Question 27

What are the attachments of the flexor digiti minimi brevis muscle of the hypothenar eminence in the hand?

Answer 27

Originates from the hook of hamate and adjacent flexor retinaculum Inserts into the base of the proximal phalanx of the little finger

Question 28

What is the action of the flexor digiti minimi brevis muscle of the hypothenar eminence in the hand?

Answer 28

Flexes the MCP joint of the little finger

Question 29

What nerve innervates the flexor digiti minimi brevis muscle of the hypothenar eminence in the hand?

Answer 29

The ulnar nerve

Question 30

How many lumbricals are there in the hand and what are each associated with?

Answer 30

4, 1 for each finger

Question 31

What do the lumbricals in the hand link?

Answer 31

The extensor tendons to the flexor tendons

Question 32

Denervation of the lumbricals of the hand is the basis for what conditions?

Answer 32

Ulnar claw | Hand of benediction

Question 33

What are the attachments of the lumbricals of the hand?

Answer 33

Each originates from a tendon of the flexor digitorum profundus Insert into extensor hood

Question 34

What root do the lumbricals take along the fingers?

Answer 34

Travel dorsally and laterally to the finger

Question 35

What is the action of the lumbricals of the hand?

Answer 35

Flexion at the MCP joint and extend at the IP joints of each finger

Question 36

What nerve innervates the lumbricals of the hand?

Answer 36

Two medial lumbricals- ulnar nerve Two lateral lumbricals- median nerve

Question 37

Where are interossei muscles found?

Answer 37

Between the metacarpals

Question 38

What are the 2 interossei muscle groups called?

Answer 38

Dorsal interossei | Palmar interossei

Question 39

What are the attachments of the dorsal interossei muscles of the hand?

Answer 39

Each originates from the lateral and medial surfaces of the metacarpals Attach into the extensor hood and proximal phalanx of each finger

Question 40

What is the action of the dorsal interossei muscles of the hand?

Answer 40

Abducts the fingers at the MCP joint | And assists the lumbricals in flexion at MCP joints and extension at the IP joints

Question 41

What nerve innervates the dorsal interossei of the hand?

Answer 41

Ulnar nerve

Question 42

How many dorsal interossei muscles are there?

Answer 42

4

Question 43

How many palmar interossei muscles are there?

Answer 43

3

Question 44

What are the attachments of the palmar interossei muscles of the hand?

Answer 44

Each originates form the medial or lateral surface of a metacarpal Attaches to the extensor hood and proximal phalanx

Question 45

What are the actions of the palmar interossei muscles of the hand?

Answer 45

Adduction of the fingers at the MCP joint | And assists the lumbricals in flexion at MCP joints and extension at the IP joints

Question 46

What nerve innervates the palmar interossei?

Answer 46

Ulnar nerve

Question 47

Name the two other muscles found in the hand that are neither lumbricals, interossei, hypothenar nor thenar muscles

Answer 47

Palmaris brevis and adductor pollicis

Question 48

What is the palmaris brevis?

Answer 48

Small, thin muscles found very superficially in the subcutaneous tissue of the hypothenar eminence

Question 49

What are the attachments of the palmaris brevis muscle in the hand?

Answer 49

Originates from the palmar aponeurosis and flexor retinaculum Attaches to the dermis of the skin on the medial margin of the hand

Question 50

What is the action of the palmaris brevis in the hand?

Answer 50

Wrinkles the skin of the hypothenar eminence and deepens the curvature of the hand, improving grip

Question 51

What nerve innervates the palmaris brevis muscle of the hand?

Answer 51

Ulnar nerve

Question 52

What is the adductor pollicis muscle of the hand?

Answer 52

Large triangular muscle with two heads- forms the deep Palmar arch

Question 53

What is the interaction of the radial artery and the adductor pollicis?

Answer 53

The radial artery passes anteriorly through the space between the two heads

Question 54

What are the attachments of the adductor pollicis muscle of the hand?

Answer 54

One head- from metacarpal 3 One head- from capitate and adjacent areas of metacarpals 2 and 3 Attach into the base of the proximal phalanx of the thumb

Question 55

What is the action of the adductor pollicis muscle of the hand?

Answer 55

Adductor of the thumb

Question 56

What nerve innervates the adductor pollicis?

Answer 56

Ulnar nerve

Question 57

What nerve innervates the hypothenar eminence?

Answer 57

The ulnar nerve