Pectoral Region: Ch 8

Question 1

identify the surface structures

Answer 1

clavicle, jugular notch, median furrow, sternal angle, xiphoid process, nipple, anterior axillary fold, deltopectoral triangle, deltopectoral groove

Question 2

what are the superficial nerves (2), arteries (2), veins (1) ?

Answer 2

1. supraclavicular nerves (C3,4) - from the cervical plexus; anterior and lateral cutaneous branches of ventral rami of thoracic spinal nerves
2. anterior perforating arteries- of the internal thoracic artery;
   lateral cutaneous branches - from posterior posterior intercostal arteries
3. cephalic vein - (see notes)

Question 3

Arterial supply of pectoral region

Answer 3

1. internal thoracic artery
2. lateral thoracic artery
3. anterior and lateral cutaneous branches of intercostal arteries 3-5

Question 4

Veins of Pectoral Region

Answer 4

venae comitantes of arterial supply (tributaries to the internal thoracic, lateral thoracic and intercostal veins)

Question 5

Lymphatic drainage of pectoral region

Answer 5

• follows venous drainage
• 75% to axillary lymph nodes
• 25% to parasternal nodes
• a slight amount drains to the opposite breast

Question 6

Pectoralis Major

Answer 6

A: adducts and medially rotates the humerus; clavicular head flexes the humerus
I: medial and lateral pectoral nerves

Question 7

Pectoralis Minor

Answer 7

A: protracts and depresses the scapula (also functions as accessory muscle to respiration)
N: medial pectoral nerve

Question 8

Subclavius

Answer 8

A: pulls lateral end of clavicle downward and forward, thereby acting to resist excessive shoulder elevation and protraction
N: nerve to subclavius

Question 9

Fascia of pectoral region

Answer 9

• clavipectoral fascia (envelopes subclavius and pectoralis minor muscles): includes costocoracoid membrane and suspensory ligament of the axilla

Question 10

costocoroid membrane

Answer 10

• term applied to the upper portion of the clavipectoral fascia (designating its medial and lateral attachments) which connects the the subclavius and pectoralis minor muslces

Question 11

what three structures pierce the costocoracoid membrane?

Answer 11

• cephalic vein
• thoracoacromial artery
• lateral pectoral nerve

Question 12

suspensory ligament of the axilla

Answer 12

• term applied to the lower portion of the clavipectoral fascia after it sweeps from both sides of the pectoralis minor to form a single thickened sheet which terminates by fusing with the axillary fascia at the floor o the axilla - this provides the dome-like configuration to the floor of the axilla