Muscle Origin, Insertion, Action Shoulder Muscles

Question 1

What is the origin of the Serratus Anterior?

Answer 1

External surfaces of ribs 1-8

Question 2

What is the insertion of the Serratus Anterior?

Answer 2

Anterior surface of medial border of scapula

Question 3

What is the action of the Serratus Anterior

Answer 3

• Protracts the scapula
• Upward rotation
• Holds scapula against thoracic wall

Question 4

What is the origin of the Pectoralis Major?

Answer 4

• Clavicular head - anterior surface of the medial half of the clavicle
• Sternocostal head - anterior surface of the sternum, superior six costal cartilage

Question 5

What is the insertion of the pectoralis major?

Answer 5

• Lateral lip of the bicipital groove of the humerus

Question 6

What is the actions of the pectoralis major?

Answer 6

Humerus
- Adduction
- Medial rotation
- Clavicular head flexes arm
- Sternocostal head will extend the humerus from flexed position

Scapula
- Draws scapula anteriorly and inferiorly

Question 7

What is the origin of the Pectoralis minor?

Answer 7

Anterior surface of ribs 3 to 5

Question 8

What is the insertion of the pectoralis minor?

Answer 8

Coracoid process of the scapula

Question 9

What are the actions of the Pectoralis Minor?

Answer 9

Scapula
- Depression
- Protraction
- Anchors

Question 10

What is the origin of the superior fibers of Trapezius?

Answer 10

• Occipital protuberance
• Spinous processes of C7
• Superior nuchal line
• Ligamentum nuchae

Question 11

What is the insertion of the superior fibers of Trapezius?

Answer 11

Clavicle
- Lateral 1/3

Scapula
- Acromion process

Question 12

What is the action of the superior fibers of the Trapezius?

Answer 12

• Elevates scapula
• Upward rotation of scapula

Question 13

What is the origin of the middle fibers of the Trapezius?

Answer 13

Spinous processes of T1 to T5

Question 14

What is the insertion of the middle fibers of the Trapezius?

Answer 14

• Medial margin of the acromion process
• Superior lip of spine of scapula

Question 15

What is the action of the middle fibers of the Trapezius?

Answer 15

Scapula retraction

Question 16

What is the origin of the inferior fibers of the Trapezius?

Answer 16

Spinus processes of T6 to T12

Question 17

What is the insertion of the inferior fibers of the Trapezius?

Answer 17

Tubercle of the apex of the spine of the scapula

Question 18

What is the action of the inferior fibers of the Trapezius?

Answer 18

• Scapula depression
• Upward rotation of the scapula

Question 19

What is the origin of the Rhomboid minor?

Answer 19

• Spinous processes of C7 and T1
• Ligamentum nuchae

Question 20

What is the insertion of the Rhomboid minor?

Answer 20

• Medial border of scapula at root of spine

Question 21

What is the action of Rhomboid minor?

Answer 21

• Scapula retraction
• Downward rotation of scapula

Question 22

What is the origin of the Rhomboid major?

Answer 22

Spinous processes of T2 to T5

Question 23

What is the insertion of the Rhomboid major?

Answer 23

Medial border of the scapula between spine and inferior angle

Question 24

What is the action of the Rhomboid major?

Answer 24

• Scapula retraction
• Downward rotation of scapula

Question 25

What is the origin of the Levator Scapulae?

Answer 25

Transverse processes of C1 to C4

Question 26

What is the insertion of the Levator Scapulae?

Answer 26

Superior Medial Border of scapula

Question 27

What is the action of the Levator Scapulae?

Answer 27

- Scapula elevation - downward rotation of scapula - Assists with lateral flexion of cervical spine

Question 28

What is the origin of the deltoid?

Answer 28

- Lateral 1/3 of clavicle - anterior border and upper surface - Acromion - Spine of scapula

Question 29

Where is the insertion of the Deltiod

Answer 29

Deltoid tuberosity of the humerus

Question 30

What is the action of the Deltoid?

Answer 30

Abduction - medial fibers Flexion - anterior fibers Extension - posterior fibers

Question 31

What is the origin of the Coracobrachialis?

Answer 31

Tip of the coracoid process of scapula

Question 32

Where is the insertion of the Coracobrachialis?

Answer 32

Middle 1/3 of the medial surface of the humerus

Question 33

What is the action of the Coracobrachialis?

Answer 33

Flexes and adducts shoulder joint

Question 34

What is the origin of the Latissimus Dorsi?

Answer 34

- Spinous processes of T6 to T12 - Thoracolumbar fascia - Iliac Crest - Ribs 8 to 12

Question 35

Where is the insertion of Latissimus Dorsi?

Answer 35

Floor of the bicipital groove

Question 36

What is the action of the Latissimus Dorsi? (3)

Answer 36

Humerus - Extends - Adducts - Medially rotates Raises body towards arms during climbing

Question 37

What is the origin of the Teres Major?

Answer 37

Posterior aspect of inferior angle of scapula

Question 38

Where does the Teres Major insert?

Answer 38

Medial lip of bicipital groove

Question 39

What are the actions of the Teres Major?

Answer 39

- Adduction of shoulder joint - Medial rotation of the shoulder joint - Extend shoulder from flexed position

Question 40

What is the origin of the Infraspinatus?

Answer 40

Infraspinatus Fossa

Question 41

Where does the infraspinatus insert?

Answer 41

Middle facet of greater tubercle of humerus

Question 42

What is the action of the Infraspinatus?

Answer 42

-Laterally rotates arm -Acts with rotator cuff muscles to hold humerus in glenoid cavity

Question 43

What is the origin of the Teres Minor

Answer 43

Middle part of lateral border of scapula

Question 44

Where is the insertion of the Teres Minor?

Answer 44

Inferior facet of greater tubercle of humerus

Question 45

What are the actions of the Teres Minor

Answer 45

- Laterally rotate arms -Acts with rotator cuff muscles to hold humerus in glenoid cavity

Question 46

What is the origin of the Subscapularis?

Answer 46

Subscapular fossa

Question 47

Where is the insertion of the Subscapularis?

Answer 47

Lesser tubercle of the humerus

Question 48

What is the action of the Subscapularis?

Answer 48

- Medially rotates the arm - Acts with rotator cuff muscles to hold humerus in glenoid cavity

Question 49

What is the origin of the Supraspinatus?

Answer 49

Supraspinatus fossa

Question 50

Where is the insertion of the Supraspinatus?

Answer 50

Superior facet of greater tubercle of humerus

Question 51

What is the action of the Supraspinatus?

Answer 51

- Initiates and assists deltoid in abduction -Acts with rotator cuff muscles to hold humerus in glenoid cavity