Dorsal Scapular Region Muscles

Question 1

Purposeful Activity of Deltoids

Answer 1

Reaching arms overhead

Reaching for (anterior) and putting on (posterior) a seatbelt

Question 2

Insertion of Deltoid

Answer 2

Deltoid tuberosity of humerus

Question 3

Origin of Deltoid

Answer 3

Spine of scapula
Acromion
Clavicle

Same as trapezius insertions

Question 4

Nerve innervation of Deltoid

Answer 4

Axillary nerve
C5, C6

Question 5

Action of Deltoid

Answer 5

Anterior/Clavicular = arm FLEXION and HELPS WITH INTERNAL ROTATION

Lateral/Acromial = arm ABDUCTION

Posterior/Spinal = arm EXTENSION and HELPS WITH EXTERNAL ROTATION

Question 6

Purposeful activity of Pectoralis Major

Answer 6

Reaching across the body into overhead cabinet

Putting on seatbelt

Question 7

Origin of Pectoralis Major

Answer 7

Clavicular Head - Clavicle

Sternocostal Head -
-Sternum
-Costal cartilages 1-6
-External oblique muscle

Question 8

Insertion of Pectoralis Major

Answer 8

LATERAL LIP of intertubercular sulcus of humerus

Question 9

Nerve innervation of Pectoralis Major

Answer 9

Lateral and medial pectoral nerves:

Clavicular head: C5, C6

Sternocostal head: C7, C8, T1

Question 10

Actions of Pectoralis Major

Answer 10

Humerus: ADDUCTION and INTERNAL/MEDIAL ROTATION

Scapula: PROTRACTION (draws scapula anteriorly and inferiorly)

Arm: HORIZONTAL ADDUCTION

Acting alone:
Clavicular head: Humerus/arm FLEXION
Sternocostal head: Humerus/arm EXTENSION from flexed position

Question 11

Purposeful activity of Pectoralis Minor

Answer 11

Taking deep breath, walking with crutches

Question 12

Origin of Pectoralis Minor

Answer 12

Ribs 3-5 near costal cartilages

Question 13

Insertion of Pectoralis Minor

Answer 13

Coracoid Process

Question 14

Nerve Innervation of Pectoralis Minor

Answer 14

Medial pectoral nerve: C8, T1

Lateral pectoral nerve: variable

Question 15

Actin of Pectoralis Minor

Answer 15

Scapular PROTRACTION
-stablizes scap by drawing it inferiorly and anteriorly

While scapula fixed, ASSISTS TO ELEVATE thorax during forced inhalation

Question 16

Purposeful activity of Teres Major

Answer 16

Toileting, perineal care

Question 17

Origin of Teres Major

Answer 17

Posterior surface of scapula’s inferior angle

Question 18

Insertion of Teres Major

Answer 18

MEDIAL LIP of intertubercular sulcus of humerus

Next to latissimus and pectoralis major! Lady b/w two majors!

Question 19

Nerve innervation of Teres Major

Answer 19

Lower subscapular nerve
C5, C6

Question 20

Actions of Teres Major

Answer 20

Shoulder ADDUCTION and INTERNAL ROTATION

Question 21

Purposeful Activity Supraspinatus

Answer 21

Washing your hair

Question 22

Origin of Supraspinatus

Answer 22

Supraspinous fossa

Question 23

Insertion of Supraspinatus

Answer 23

Greater Tubercle of Humerus

Question 24

Nerve innervation of Supraspinatus

Answer 24

Suprascapular nerve
C4, C5, C6

Question 25

Action of Supraspinatus

Answer 25

Stabilizes head of humerus in glenoid cavity INITIATES and ASSISTS deltoid in ABDUCTION

Question 26

Purposeful activity of Infraspinatus

Answer 26

Playing racket sports or table tennis

Question 27

Origin of Infraspinatus

Answer 27

Infraspinous fossa

Question 28

Insertion of Infraspinatus

Answer 28

Greater tubercle of humerus

Question 29

Nerve innervation of Infraspinatus

Answer 29

Suprascapular nerve C5, C6

Question 30

Action of Infraspinatus

Answer 30

Stabilizes head of humerus in glenoid cavity Shoulder EXTERNAL ROTATION

Question 31

Purposeful activity of Teres Minor

Answer 31

Washing back of your head and neck

Question 32

Origin of Teres Minor

Answer 32

Lateral border of scapula

Question 33

Insertion of Teres minor

Answer 33

Greater tubercle of humerus

Question 34

Nerve Innervation of Teres minor

Answer 34

Axillary nerve C5, C6

Question 35

Action of Teres minor

Answer 35

Stabilizes head of humerus in glenoid cavity Shoulder EXTERNAL ROTATION

Question 36

Purposeful activity of Subscapularis

Answer 36

Toileting, donning a bra, throwing a baseball

Question 37

Origin of Subscapularis

Answer 37

Subscapular fossa (most of scapula's anterior surface)

Question 38

Insertion of Subscapularis

Answer 38

Lesser tubercle of humerus

Question 39

Nerve innervation of Subscapularis

Answer 39

Upper and lower subscapular nerves C5, C6, C7

Question 40

Action of Subscapularis

Answer 40

Stabilize head of humerus in glenoid cavity Shoulder INTERNAL ROTATION

Question 41

Purposeful activity of Serratus Anterior

Answer 41

Pushing open a heavy door, punching

Question 42

Origin of Serratus Anterior

Answer 42

Lateral part of ribs 1-8 or 1-9

Question 43

Insertion of Serratus Anterior

Answer 43

Medial Border of Scapula

Question 44

Nerve innervation of Serratus Anterior

Answer 44

Long Thoracic Nerve C5, C6, C7

Question 45

Action of Serratus Anterior

Answer 45

Scapular PROTRACTION and UPWARD ROTATION HOLDS scapula against thoracic wall