Muscles of the Upper Limb

Question 0

Innervation of pectoralis major

Answer 0

Medial pectoral nerve
Lateral pectoral nerve
Origins in C7, C8 and T1 to the lower trunk of the brachial plexus

Question 1

Describe the function of the pectoralis major.

Answer 1

Medial rotation of the arm

Question 2

Function of the deltoid

Answer 2

Anterior fibres - flexion of the arm (clavicular)
Middle fibres - abduction from 15-90 degrees (acromial)
Posterior fibres - extention (spinal)

Question 3

Innervation of the deltoid

Answer 3

Axillary nerve from the ventral rami of C5 and C6 to the posterior cord of the brachial plexus

Question 4

Function of pectoralis minor

Answer 4

Stabalises the scapula by drawing it inferiorly and anteriorly

Question 5

Innervation of the pectoralis minor

Answer 5

Medial pectoral nerve (C8, T1)

Question 6

Function of the subclavius

Answer 6

Depresses the clavicle

Can protect underlying structures if the clavicle is fractured

Question 7

Innervation of the subclavius

Answer 7

Nerve to subclavius

Question 8

Function of the serratus anterior

Answer 8

Abduction of the scapula to assist the deltoid in abducting the arm.

Question 10

Innervation of the serratus anterior

Answer 10

Long thoracic nerve from roots C5,6,7 of the brachial plexus

Question 11

Innervation of the extensor carpi ulnaris

Answer 11

Posterior interosseus nerve (deep branch of the radial nerve)

Question 12

Function of extensor carpi ulnaris

Answer 12

Extends and adducts the wrist

Question 13

Innervation of extensor digiti minimi

Answer 13

Posterior interosseus nerve (deep branch of the radial nerve)

Question 14

Function of extensor digiti minimi

Answer 14

Extends the little finger

Question 15

Innervation of extensor digitorum

Answer 15

Posterior interosseus nerve (deep branch of the radial nerve)

Question 16

Function of extensor digitorum

Answer 16

Extends the four fingers and the wrist

Question 17

Function of the aconeus

Answer 17

Abduction of the ulna

Accessory extension at the elbow

Question 18

Innervation of the aconeus

Answer 18

Radial nerve

Question 19

Function of extensor carpi radialis longus

Answer 19

Extend and abduct the wrist

Question 20

Innervation of extensor carpi radialis longus

Answer 20

Radial nerve

Question 21

Function of extensor carpi radialis brevis

Answer 21

Extend and abduct the wrist

Question 22

Innervation of extensor carpi radialis brevis

Answer 22

Deep branch of the radial nerve`

Question 23

Function of extensor pollicus longus

Answer 23

Extends all joints of the thumb

Question 24

Innervation of extensor pollicus longus

Answer 24

Posterior interosseus nerve (deep branch of the radial nerve)

Question 25

Function of extensor indices

Answer 25

Extends the index finger

Question 26

Innervation of extensor indices

Answer 26

Posterior interosseus nerve (deep branch of the radial nerve)

Question 27

Function of supinator

Answer 27

Supination of the forearm

Question 28

Innervation of the supinator

Answer 28

Posterior interosseus nerve (deep branch of the radial nerve)

Question 29

Function of the abductor pollicus longus

Answer 29

Accessory extensor of the thumb for abduction

Question 30

Innervation of abductor pollicus longus

Answer 30

Posterior interosseus nerve (deep branch of the radial nerve)

Question 31

Function of extensor pollicus brevis

Answer 31

Extends the metacarpophalangeal/carpometacarpal joints

Question 32

Innervation of extensor pollicus brevis

Answer 32

Posterior interosseus nerve (deep branch of the radial nerve)

Question 33

What is the extensor retinaculum?

Answer 33

The aponeurosis across the back of the wrist which covers and acts as an insertion point for extensor muscles of the forearm.

Question 34

Function of opponens pollicis

Answer 34

Oppose the thumb by rotating and flexing at the metacarpophalangeal joint.

Question 35

Innervation of opponens pollicis

Answer 35

Median nerve

Question 36

Function of abductor pollicis brevis

Answer 36

Abducts the thumb

Question 37

Innervation of abductor pollicis brevis

Answer 37

Median nerve

Question 38

Function of flexor pollicis brevis

Answer 38

Flexes the metacarpophalangeal joint of the thumb

Question 39

Innervation of flexor pollicis brevis

Answer 39

Median nerve

Question 40

Function of opponens digiti minimi

Answer 40

Rotates the metacarpal of the little finger towards the thumb for opposition

Question 41

Innervation of opponens digiti minimi

Answer 41

Ulnar nerve

Question 42

Function of abductor digiti minimi

Answer 42

Abducts the little finger

Question 43

Innervation of abductor digiti minimi

Answer 43

Ulnar nerve

Question 44

Function of flexor digiti minimi brevis

Answer 44

Flexes the little finger

Question 45

Innervation of flexor digiti minimi brevis

Answer 45

Ulnar nerve

Question 46

Function of the lumbricles

Answer 46

Flex at the metacarpophalangeal joint and extend at the interphalangeal joint

Question 47

Innervation of the lumbricles

Answer 47

Medial two by the ulnar nerve | Lateral two by the median nerve

Question 48

How many dorsal interossei muscles are there?

Answer 48

4

Question 49

Function of the dorsal interossei

Answer 49

Abduct the fingers at the metacarpophalangeal joint

Question 50

Innervation of dorsal interossei

Answer 50

Ulnar nerve

Question 51

How many palmar interossei muscles are there?

Answer 51

3

Question 52

Function of the palmar interossei

Answer 52

Adduct the fingers at the metacarpophalangeal joint

Question 53

Innervation of the palmar interossei

Answer 53

Ulnar nerve

Question 54

Function of palmaris brevis

Answer 54

Deepens the curvature of the hand, improving grip

Question 55

Innervation of palmaris brevis

Answer 55

Ulnar nerve

Question 56

Function of adductor pollicis

Answer 56

Adduct the thumb

Question 57

Innervation of adductor pollicis

Answer 57

Ulnar nerve

Question 58

What are the two muscles in the palm of the hand?

Answer 58

Palmaris brevis | Adductor pollicis

Question 59

What are the muscles of the thenar eminence?

Answer 59

Opponens pollicis Abductor pollicis brevis Flexor pollicis brevis

Question 60

What are the muscles of the hypothenar eminence?

Answer 60

Opponens digiti minimi Abductor digiti minimi Flexor digiti minimi brevis