Regional Anatomy: Pectoral Region

Question 1

What does the cylindrical thorax consist of?

Answer 1

A wall, two pleural cavities, lungs, mediastinum

Question 2

What does the pectoral region consist of?

Answer 2

Superficial compartment containing skin, superficial fascia, and breasts. Also a deep compartment containing muscles and associated structures

Question 3

Innervation of the Breast

Answer 3

Anterior and lateral cutaneous branches of second to sixth intercostal nerves. Nipple innervated by fourth intercostal nerve.

Question 4

Lymphatic Drainage of Breast

Answer 4

75% to axillary nodes, remaining drainage to parasternal and intercostal

Question 5

Origin of Pec Major

Answer 5

Medial half of clavicle and anterior surface of sternum, first seven costal cartilages, aponeurosis of external oblique

Question 6

Insertion of Pec Major

Answer 6

Lateral lip of intertubercular sulcus of humerus

Question 7

Innervation of Pec Major

Answer 7

Medial and Lateral Pectoral Nerves

Question 8

Function of Pec Major

Answer 8

Adduction, medial rotation, flexion of humerus at shoulder joint

Question 9

Origin of Subclavius

Answer 9

Rib I at jxn b/t rib and costal cartilage

Question 10

Insertion of Subclavius

Answer 10

Groove on inferior surface of middle third of clavicle

Question 11

Innervation of Subclavius

Answer 11

Nerve to Subclavius

Question 12

Function of Subclavius

Answer 12

Pulls clavicle medially to stabilize sternoclavicular joint

Question 13

Origin of Pec Minor

Answer 13

Anterior surfaces of 3rd, 4th, and 5th ribs, and deep fascia overlying related intercostal spaces

Question 14

Insertion of Pec Minor

Answer 14

Coracoid process of scapula

Question 15

Innervation of Pec Minor

Answer 15

Medial pectoral nerves

Question 16

Function of Pec Minor

Answer 16

Depresses tip of shoulder; protracts scapula