Muscles

Question 1

What is the motor innervation of trapezius?

Answer 1

spinal accessory nerve

Question 2

What is the sensory innervation of trapezius?

Answer 2

C3 and C4 spinal roots

Question 3

What is the lateral attachment of the trapezius?

Answer 3

lateral third of the clavicle, acromion and spine of the scapula

Question 4

What is the medial attachment of the trapezius?

Answer 4

medial third of the superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7 - T12 vertebrae

Question 5

What is the main action of the upper fibres of trapezius?

Answer 5

elevate the scapula and rotate it during abduction of the arm

Question 6

What is the main action of the middle fibres of the trapezius?

Answer 6

retract the scapula

Question 7

What is the main action of the lower fibres of the trapezius?

Answer 7

pull the scapular inferiorly

Question 8

What are the main actions of latissimus dorsi?

Answer 8

extends, abducts and medially rotates humerus; raises body toward arms during climbing

Question 9

What is the innervation of latissimus dorsi?

Answer 9

thoracodorsal nerve

Question 10

What muscles form the rotator cuff?

Answer 10

supraspinatous, infraspinatous, teres minor and subscapularis

Question 11

What is the innervation of the deltoid?

Answer 11

axillary nerve

Question 12

What is the innervation of serratus anterior?

Answer 12

long thoracic nerve

Question 13

What is the innervation of supraspinatus?

Answer 13

suprascapular nerve

Question 14

What is the innervation of infraspinatus?

Answer 14

suprascapular nerve

Question 15

What is the proximal attachment of supraspinatus?

Answer 15

supraspinous fossa of scapula

Question 16

What is the proximal attachment of infraspinatus?

Answer 16

infraspinous fossa of scapula

Question 17

What is the innervation of teres minor?

Answer 17

axillary nerve

Question 18

What is the proximal attachment of the deltoid?

Answer 18

lateral third of the clavicle, acromion, spine of scapula

Question 19

What is the distal attachment of the deltoid?

Answer 19

deltoid tuberosity of humerus

Question 20

What is the proximal attachment of subscapularis?

Answer 20

subscapular fossa

Question 21

What is the innervation of subscapularis?

Answer 21

upper and lower subscapular nerves

Question 22

What are the actions of subscapularis?

Answer 22

responsible for the first 15 degrees of abduction, assists deltoid for the rest, acts with other rotator cuff muscles

Question 23

What is the distal attachment of infraspinatus?

Answer 23

middle facet of greater tubercle of humerus

Question 24

What is the distal attachment of supraspinatus?

Answer 24

superior facet of greater tubercle of humerus

Question 25

Name the 6 scapulohumeral muscles

Answer 25

deltoid, teres major, supraspinatus, infraspinatus, subscapularis, teres minor

Question 26

What are the three flexors in the arm?

Answer 26

biceps brachii, brachialis, coracobrachialis

Question 27

What is the extensor in the arm?

Answer 27

triceps brachii

Question 28

What nerve supplies the the flexor arm muscles?

Answer 28

musculocutaneous

Question 29

What nerve supplies the extensor arm muscle?

Answer 29

radial nerve

Question 30

What is the main action of biceps brachii?

Answer 30

supinates forearm and, when it is supinated, flexes forearm; flexes arm

Question 31

What is the proximal attachment of the short head of biceps brachii?

Answer 31

tip of coracoid process

Question 32

What is the proximal attachment of the long head of biceps brachii?

Answer 32

supraglenoid tubercle of scapula

Question 33

What is the distal attachment of the biceps brachii?

Answer 33

tuberosity of the radius

Question 34

Where are the flexors and protonators of the forearm located?

Answer 34

anterior compartment

Question 35

Where are the extensors and supinators of the forearm located?

Answer 35

posterior compartment

Question 36

What are the muscles of the superficial layer of the anterior compartment of the forearm?

Answer 36

pronator teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris

Question 37

What muscle is the exception to the rule that all flexors lie in the anterior compartment and that the radial nerve supplies only extensor muscles?

Answer 37

brachioradialis

Question 38

How can palmaris longus be identified?

Answer 38

long, thin tendon (absent in about 15% of the population)

Question 39

What is the muscle of the intermediate layer of the anterior compartment of the forearm?

Answer 39

flexor digitorum superficialis

Question 40

What is the innervation of pronator teres?

Answer 40

median nerve

Question 41

What is the innervation of flexor carpi ulnaris?

Answer 41

ulnar nerve

Question 42

What is the innervation of flexor carpi radialis?

Answer 42

median nerve

Question 43

What is the innervation of flexor digitorum superficialis?

Answer 43

median nerve

Question 44

What muscles are located in the deep layer of the anterior compartment of the forearm?

Answer 44

flexor digitorum profundus, flexor pollicus longus, pronator quadratus

Question 45

What is the innervation of flexor digitorum profundus?

Answer 45

medial aspect supplied by the ulnar nerve (4th to 5th digit) lateral aspect supplied by median nerve (2nd and 3rd digit)

Question 46

What is the main action of pronator teres?

Answer 46

Question 47

What is the main action of flexor carpi radialis?

Answer 47

flexes and abducts hand at wrist

Question 48

What is the main action of flexor carpi ulnaris?

Answer 48

flexes and abducts hand at wrist

Question 49

What is the main action of palmaris longus?

Answer 49

flexes hand at wrist

Question 50

What is the main action of flexor pollicis longus?

Answer 50

flexes thumb

Question 51

What nerve are the extensor muscles of the forearm innervated by?

Answer 51

radial nerve

Question 52

How many muscles are in the superficial layer of the posterior forearm?

Answer 52

6

Question 53

Why is brachioradialis different from the other extensor muscles?

Answer 53

it is a flexor at the elbow, but has the same origin and innervation as the other extensor muscles in the posterior compartment

Question 54

What is the proximal attachment of brachioradialis?

Answer 54

lateral supraepicondylar ridge of humerus

Question 55

What is the distal attachment of brachioradialis?

Answer 55

lateral surface of distal end of radius proximal to styloid process

Question 56

What are the actions of extensor carpi radialis longus and brevis?

Answer 56

extend and abduct hand at the wrist joint

Question 57

What is the main action of extensor digitorum?

Answer 57

extends medial four fingers

Question 58

What is the main action of extensor digiti minimi?

Answer 58

extends fifth finger

Question 59

What is the main action of extensor carpi ulnaris?

Answer 59

extends and adducts hand at the wrist joint

Question 60

What is the main action of the supinator muscle?

Answer 60

supinates forearm, rotates radius to turn palm anteriorly or superiorly

Question 61

Name the muscles that extend and abduct or adduct the hand at the wrist joint

Answer 61

extensor carpi radialis longus, extensor carpi radialis brevis, extensor carpi ulnaris (carpi = wrist)

Question 62

Name the muscles that extend the medial four digits

Answer 62

extensor digitorum, extensor indicis, extensor digiti minimi

Question 63

Name the muscles that extend or abduct the thumb

Answer 63

abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus