SHOULDER MUSCLE

Question 1

Which muscles make up the rotator cuff?

Answer 1

Supraspinatus, Infraspinatus, Teres Minor, Subscapularis.

Question 2

What is the function of the rotator cuff muscles?

Answer 2

Stabilize the shoulder, rotate the humerus, prevent dislocation.

Question 3

What is the mnemonic for the rotator cuff muscles?

Answer 3

SITS on the shoulder.

Question 4

Where does the supraspinatus muscle originate?

Answer 4

Supraspinous fossa of the scapula.

Question 5

Where does the supraspinatus insert?

Answer 5

Greater tubercle of the humerus.

Question 6

What nerve innervates the supraspinatus?

Answer 6

Suprascapular nerve (C4-C6).

Question 7

What is the action of the supraspinatus?

Answer 7

Initiates abduction of the arm to 15 degrees.

Question 8

Where does the infraspinatus originate?

Answer 8

Infraspinous fossa of the scapula.

Question 9

Where does the infraspinatus insert?

Answer 9

Greater tubercle of the humerus.

Question 10

What nerve innervates the infraspinatus?

Answer 10

Suprascapular nerve (C5-C6).

Question 11

What is the action of the infraspinatus?

Answer 11

External rotation of the arm.

Question 12

Where does the teres minor originate?

Answer 12

Lateral border of the scapula.

Question 13

Where does the teres minor insert?

Answer 13

Greater tubercle of the humerus.

Question 14

What nerve innervates the teres minor?

Answer 14

Axillary nerve (C5-C6).

Question 15

What is the action of the teres minor?

Answer 15

External rotation and adduction of the arm.

Question 16

Where does the subscapularis originate?

Answer 16

Subscapular fossa of the scapula.

Question 17

Where does the subscapularis insert?

Answer 17

Lesser tubercle of the humerus.

Question 18

What nerve innervates the subscapularis?

Answer 18

Upper and lower subscapular nerves (C5-C7).

Question 19

What is the action of the subscapularis?

Answer 19

Internal rotation of the arm and stabilization of the humeral head.

Question 20

Where does the deltoid muscle originate?

Answer 20

Spine of the scapula, acromion, clavicle.

Question 21

Where does the deltoid insert?

Answer 21

Deltoid tuberosity of the humerus.

Question 22

What is the function of the deltoid (acromial part)?

Answer 22

Abducts the arm.

Question 23

What is the function of the deltoid (clavicular part)?

Answer 23

Internally rotates the arm.

Question 24

What is the function of the deltoid (spinal part)?

Answer 24

Externally rotates the arm.

Question 25

Where does the teres major originate?

Answer 25

Inferior angle and lateral border of the scapula.

Question 26

Where does the teres major insert?

Answer 26

Crest of the lesser tubercle of the humerus.

Question 27

What is the action of the teres major?

Answer 27

Adducts, extends, and internally rotates the arm.

Question 28

Where does the latissimus dorsi originate?

Answer 28

Spinous processes of T7-T12, iliac crest, inferior scapula, ribs.

Question 29

Where does the latissimus dorsi insert?

Answer 29

Intertubercular sulcus of the humerus.

Question 30

What is the function of the latissimus dorsi?

Answer 30

Internally rotates, adducts, extends the arm; assists in respiration.

Question 31

Where does the serratus anterior originate?

Answer 31

Ribs 1-9.

Question 32

Where does the serratus anterior insert?

Answer 32

Scapula.

Question 33

What is the function of the serratus anterior?

Answer 33

Draws the scapula anterolaterally.

Question 34

Where does the pectoralis major originate?

Answer 34

Clavicular part, sternocostal part, costal cartilages.

Question 35

Where does the pectoralis major insert?

Answer 35

Crest of the greater tubercle of the humerus.

Question 36

What is the function of the pectoralis major?

Answer 36

Adducts, internally rotates, and flexes the arm.

Question 37

Where does the trapezius originate?

Answer 37

Nuchal line and transverse processes.

Question 38

Where does the trapezius insert?

Answer 38

Clavicle, acromion, spine of the scapula.

Question 39

What is the function of the trapezius?

Answer 39

Draws the scapula superomedially and laterally extends the head.