Muscles of Shoulder & Arm

Question 1

What muscles attach the pectoral girdle to the trunk from the thoracic wall?

Answer 1

pec major, pec minor, subclavius, serratus anterior

Question 2

What muscles attach the pectoral girdle to the trunk from the vertebral column?

Answer 2

trapezius, lat dorsi, rhomboid major, rhomboid minor, levator scapulae

Question 3

What is the origin and insertion of pec major?

Answer 3

clavicular and sternocostal head with an insertion on proximal humerus

Question 4

What is the action of pec major?

Answer 4

adduction and medial rotation of the upper limb and an accessory muscle of respiration if the humerus is fixed

Question 5

What is the origin and insertion of pec minor?

Answer 5

costal cartiage or ribs 3,4,5 and inserts on the coracoid process

Question 6

What is the action of pec minor?

Answer 6

stabilises scapula and depresses the shoulder an an accessory muscle of inspiration

Question 7

What is the origin and insertion of subclavius?

Answer 7

origin on the anteromedial part of first rib and insertion on the lateral inferior surface of the clavicle

Question 8

What is action of subclavius?

Answer 8

stabilises clavicle and depresses shoulder

Question 9

What is the origin and insertion of serratus anterior?

Answer 9

saw tooth attachment on ribs 1-8 and inserts on the medial border of the scapula

Question 10

What is the action of serratus anterior?

Answer 10

reaching forward - allows scapula to travel around chest wall - boxers muscle

Question 11

What is the nerve supply of serratus anterior?

Answer 11

long thoracic nerve

Question 12

What do you see in a patient with a damaged long thoracic nerve?

Answer 12

winged scapula

Question 13

What muscles attach the humerus to the scapula?

Answer 13

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

Question 14

What is the origin and insertion of deltoid?

Answer 14

origin the spine of the scapula, the acromion process and the clavicle and inserts on the deltoid tubercle on the humerus

Question 15

What is the action of deltoid?

Answer 15

powerful abducter - but can’t initiate abduction - also flexion and extension

Question 16

What are the muscles of the rotator cuff?

Answer 16

supraspinatus, infraspinatus, subscapularis and teres minor

Question 17

What is the feature of all muscles of the rotator cuff?

Answer 17

they blend with the capsule of the shoulder joint

Question 18

Where do supraspinatus, infraspinatus and teres minor all insert?

Answer 18

on the greater tubercle of the humerus

Question 19

What is the action of supraspinatus?

Answer 19

initiates abduction

Question 20

What is the action of infraspinatus and teres minor?

Answer 20

lateral rotation

Question 21

What is the insertion of subscapularis?

Answer 21

lesser tubercle of the humerus

Question 22

What is the action of subscapularis?

Answer 22

medial rotator

Question 23

From what muscle is teres major derived?

Answer 23

subscapularis

Question 24

What is the origin of teres major?

Answer 24

inferior angle of the scapula

Question 25

What is the action of teres major?

Answer 25

abducts and medially rotates

Question 26

What are the muscles of the anterior compartment of the arm?

Answer 26

biceps brachii, coracobrachialis, brachialis

Question 27

What is the origin of the long head of biceps?

Answer 27

supraglenoid tubercle

Question 28

What is the origin of the short head of biceps?

Answer 28

coracoid process

Question 29

What is the insertion of biceps tendon?

Answer 29

radial tuberosity

Question 30

What is the action of biceps brachii?

Answer 30

flexion at the elbow and supination when elbow is flexed

Question 31

What is the origin of brachialis?

Answer 31

distal half of shaft of the humerus

Question 32

What is the insertion of brachialis?

Answer 32

coranoid process of the ulna

Question 33

What is the action of brachialis?

Answer 33

flexion at the elbow

Question 34

What is the origin of coracobrachialis?

Answer 34

coracoid process

Question 35

What is the insertion of coracobrachialis?

Answer 35

shaft of the mid humerus

Question 36

What is the action of coracobrachialis?

Answer 36

flexion and adduction at the shoulder

Question 37

What is the origin of the long head of triceps?

Answer 37

infraglenoid tubercle

Question 38

What is the origin of the lateral head of triceps?

Answer 38

linear origin on the proximal part of the posterior aspect of humerus

Question 39

What is the origin of the medial (deep) head of triceps?

Answer 39

clothes the posterior aspect of the shaft of humerus

Question 40

What is the insertion of triceps?

Answer 40

olecranon of the ulna

Question 41

What is the action of triceps?

Answer 41

extension at the elbow