Shoulder Muscles

Question 1

What are the 9 muscles of the shoulder joint?

Answer 1

Pectoralis Major
Latissimus Dorsi
Deltoid

Coracobrachialis

Teres Minor
Infraspinatus
Teres Major
Supraspinatus
Subscapularis

Question 2

Pectoralis Major - Origin - two heads

Answer 2

Clavicular Head
O= Medial half of clavicle

Sternal Head
O= Sternum and costal cartilidge (1-6)

Question 3

Pectoralis Major - Insertsion

Answer 3

I= Greater tubercle crest of Humerus

Question 4

Pectoralis Major - Actions - Clavicular head

Answer 4

Shoulder Horizontal adduction
Medial rotation of the shoulder

Assists with shoulder flexion

Question 5

Pectoralis Major - Actions - Sternal head

Answer 5

Shoulder Horizontal adduction
Shoulder adduction
Medial rotation of the shoulder

Assists with Shoulder extension

Question 6

Latissimus Dorsi - Origin (5 - R Sits)

Answer 6

R - Ribs - Lower 3 or 4

S - Sacrum
I - Iliac Crest
T - Thoracolumbar Fascia
S - Spine - Thoracic 7-12 & Lumbar 1-5

Question 7

Latissimus Dorsi - Insertion

Answer 7

I= Humerus - Floor of intertubercular groove

Question 8

Latissimus Dorsi - Actions

Answer 8

Shoulder Extension
Shoulder Adduction
Shoulder Internal (Medial) rotation

Question 9

Deltoid - Anterior - Origin

Answer 9

O= Lateral 1/3 of clavicle

Question 10

Deltoid - Anterior - Insertion

Answer 10

I= Deltoid tuberosity of Humerus

Question 11

Deltoid - Anterior - Actions 4

Answer 11

Shoulder Flexion

Assists with:
Horizontal Shoulder Adduction
Shoulder Abduction
Shoulder internal (medial) rotation

Question 12

Deltoid - Middle - Origin

Answer 12

O= Scapula - Acromion - lateral margin, superior surface

Question 13

Deltoid - Middle - Insertion

Answer 13

I= Deltoid Tuberosity of Humerus

Question 14

Deltoid - Middle - Actions 2

Answer 14

Shoulder Abduction

Assists with shoulder flexion

Question 15

Deltoid - Posterior - Origin

Answer 15

O= Spine of the scapula - Inferior lip of posterior border

Question 16

Deltoid - Posterior - Insertion

Answer 16

I= Humerus - Deltoid tuberosity

Question 17

Deltoid - Posterior - Actions

Answer 17

Horizontal Shoulder Abduction
Shoulder external rotation

Assists with:
Shoulder extension

Question 18

Coracobrachialis - Origin

Answer 18

O= Scapula, coracoid process

Question 19

Coracobrachialis - Insertsion

Answer 19

I= Humerus, proximal 1/3, medial border

Question 20

Coracobrachialis - Actions

Answer 20

Shoulder Flexion

Assists with:
Shoulder Adduction
Horizontal Shoulder Adduction

Question 21

Supraspinatus - Origin

Answer 21

O= Scapula - Supraspinatus Fossa

Question 22

Supraspinatus - Insertsion

Answer 22

I = Humerus - Greater Tuberosity

Question 23

Supraspinatus - Actions

Answer 23

Shoulder Abduction

Question 24

Infraspinatus - Origin

Answer 24

O= Scapula - Infraspinatus Fossa

Question 25

Infraspinatus - Insertion

Answer 25

I= Humerus - Greater Tuberosity

Question 26

Infraspinatus - Actions

Answer 26

Shoulder external rotation

Assists with:
Shoulder Horizontal Abduction
Shoulder Abduction

Question 27

Subscapularis - Origin

Answer 27

O= Scapula - Subscapular Fossa

Question 28

Subscapularis - Insertion

Answer 28

I= Humerus - Lesser Tuberosity

Question 29

Subscapularis - Actions

Answer 29

Shoulder Internal (Medial) Rotation

Assists Shoulder Abduction

Question 30

Teres Minor - Origin

Answer 30

O= Scapula - Lateral Border

Question 31

Teres Minor - Insertion

Answer 31

I= Humerus - Greater Tuberosity

Question 32

Teres Minor - Actions

Answer 32

Shoulder External Rotation

Assists:
Horizontal Shoulder Abduction

Question 33

Name the 4 Rotator Cuff muscles

Answer 33

Supraspinatus
Infraspinatus
Subscapularis
Teres Minor

Question 34

Teres Major - Origin

Answer 34

O= Scapula - Inferior Angle

Question 35

Teres Major - Insertion

Answer 35

I= Humerus - Lesser Tuberosity

Question 36

Teres Major - Actions

Answer 36

Shoulder Medial (Internal) Rotation
Shoulder Adduction

Assists:
Shoulder Extension