Axilla, Pectoral, and Deltoid

Question 1

Pectoralis Major

Answer 1

O: Clavicular Head: Anterior surface of medial half of clavicle
Sternocostal Head:
1. Anterior surface of sternum
2. Superior six costal cartilages
3. Aponeurosis of external oblique muscle
I: Lateral lip of inter tubercular sulcus of humerus
N: 1. Lateral Pectoral Nerve
2. Medial Pectoral Nerve
A: 1. Adducts Humerus
2. Medially rotates humerus
3. Draws scapula anteriorly and inferiorly
4. Clavicular Head: Flexes humerus
5. Sternocostal head: Extends humerus from flexed position

Question 2

Pectoralis Minor

Answer 2

O: 3rd-5th ribs near their costal cartilages
I: Medial Border and Superior Surface of coracoid process of scapula
N: 1. Lateral Pectoral Nerve
2. Medial Pectoral Nerve
A: 1. Stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall

Question 3

Subclavius

Answer 3

O: Junction of 1st rib and its costal cartilage
I: Inferior surface of middle third of clavicle
N: Nerve to Subclavius
A: Anchors and depresses clavicle

Question 4

Serratus Anterior

Answer 4

O: External surfaces of lateral parts of 1st-8th ribs
I: Anterior surface of medial border of scapula
N: Long Thoracic Nerve C5, C6, C7
A: 1. Protracts scapula and holds it against thoracic wall
2. Rotates scapula

Question 5

Coracobrachialis

Answer 5

O:  Tip of coracoid process of scapula
I:  Middle third of medial surface of humerus
N:  Musculocutaneous Nerve
A: 1. Helps flex and adduct arm
    2.  Resist dislocation of shoulder

Question 6

Biceps Brachii

Answer 6

O: Short Head: Tip of coracoid process of scapula
Long Head: Supraglenoid tubercle of scapula
I: Tuberosity of radius and fascia of forearm via bicipital aponeurosis
N: Musculocutaneous Nerve C5, C6
A: 1. Supinates forearm and, when supine, flexes forearm
2. Short head resists dislocation of shoulder

Question 7

Subscapularis

Answer 7

O:  Subscapular fossa
I:  Lesser Tubercle of Humerus
N:  1.  Upper Subscapular Nere
     2.  Lower Subscapular Nreve
A:  1.  Medially Rotates Arm
     2.  As part of rotator cuff, helps hold head of humerus in glenoid cavity

Question 8

Teres Major

Answer 8

O: Posterior surface of interior angle of scapula
I: Medial lip of inter tubercular sulcus of humerus
N: Lower Subscapular Nerve
A. 1. Adducts arm
2. medially rotates arm

Question 9

Latissimus Dorsi

Answer 9

O: 1. Spinous processes of inferior 6 thoracic vertebrae
2. Thoracolumbar fascia
3. Iliac crest
4. Inferior 3 or 4 ribs
I: Floor of inter tubercular sulcus of humerus
N: Thoracodorsal Nerve C6, C7, C8
A: 1. Extends, adducts, and medially rotates humerus
2. Raises body toward arms when climbing

Question 10

Deltoid

Answer 10

O: 1. Lateral Third of clavicle
2. Acromion and spine of scapula
I: Deltoid tuberosity of humerus
N: Axillary Nerve C5, C6
A: 1. Clavicular (anterior) part: flexes and medially rotates arm
2. Acromial (middle) part: abducts arm
3. Spinal (posterior) part: extends and laterally rotates arm