Anatomy: Breast and Pectoral Region

Question 0

Serratus Anterior

Answer 0

N: long thoracic
A: protract and rotate scapula
O: ribs 1-8
I: anterior surface of medial scapula

Question 1

Triceps Brachii

Answer 1

N: radial
A: extend forearm and arm, long head resists dislocation of humerus during adduction
O: long head - infraglenoid tubercle of scapula, lateral head - posterior surface of humerus superior to radial groove, medial head - posterior surface of humerus inferior to radial groove
I: olecranon of ulna and fascia of forearm

Question 2

Pectoralis Major

Answer 2

N: lateral and medial pectoral
A: adducts and medially rotates humerus, clavicular head: flex humerus, sternocostal head: extend humerus from flexed position
O: clavicular head: medial half of clavicle, sternocostal head: sternum, superior 6 costal cartilages, aponeurosis of external oblique
I: lateral lip of inter tubercular sulcus of humerus

Question 3

Pectoralis Minor

Answer 3

N: medial pectoral
A: stabilize scapula, draw scapula inferiorly and anteriorly against thoracic wall
O: ribs 3-5
I: coracoid process of scapula

Question 4

Subclavius

Answer 4

N: nerve to subclavius
A: anchors and depresses clavicle
O: 1st rib and first costal cartilage
I: middle third of clavicle