Pectoral and Axillary Regions

Question 1

Osteology of the Pectoral Region

Answer 1

clavicle
sternum (manubrium, body, xiphoid)
ribs
scapula

Question 2

Atypical Ribs

Answer 2

1, 2, 11, and 12

Question 3

True Ribs (vertebrocostal)

Answer 3

1-7

Question 4

False Ribs (vertebrochondral)

Answer 4

8-10

Question 5

Floating Ribs

Answer 5

11-12

Question 6

The Breast

Answer 6

cutaneous
modified sweat glands
on pectoral fascia 
retromammary spaces b/w breast and pectoral fascia
inn. by intercostal n. 4-6
attached to skin by Cooper's Ligaments
mammary glands lobules converge on the nipple 
15-20 lactiferous ducts open at nipple

Question 7

Arterial Supply - Breast

Answer 7

mammary branches from anterior intercostal, lateral thoracic, and internal thoracic arteries

Question 8

Venous Drainage - Breast

Answer 8

mainly to axillary vein via lateral thoracic veins and medial mammary veins
some drainage to internal thoracic vein via anterior intercostal veins

Question 9

Lymphatic Drainage - Breast

Answer 9

more that 75% of lymph from breast - AXILLARY lymph nodes
nipple, areola, lactiferous lobules - subareolar lymph nodes
remaining lymph - parasternal and abdominal lymph nodes

Question 10

Innervation - Breast

Answer 10

mainly from ANT. and LAT. BRANCHES of the 4th-6th INTERCOSTAL N.
some from supraclavicular n branches as well as branches of other intercostal n.

Question 11

Polymastia and Polytheia

Answer 11

accessory breast and accessory nipples along the mammary ridge

Question 12

Superficial Fascia - Pectoral Region

Answer 12

platysma
supraclavicular n.
anterior and lateral branches of intercostal n.

Question 13

Deltopectoral (clavipectoral) Triangle

Answer 13

deltoid, pectorals major, middle 1/3 of clavicle make up borders
cephalic vein
detopectoral lymph nodes
deltoid branch of thoracoacromial a. (from axillary a.)

Question 14

Clavipectoral Fascia

Answer 14

invests subclavius and pectoralis minor
attaches to clavicle and anterior thoracic wall
cephalic vein, thoracoacromial a, and lateral pectoral n pierce it
becomes suspensory ligament of axilla

Question 15

Pectoralis major m.

Answer 15

Actions: ADducts and medial rotation of humerus, flexion of humerus (clavicular portion), anteriorly and inferior movement of scapula, extend humerus while flexed (sternal portion)

Blood supply: pectoral branch of thoracoacromial arterial trunk

Inn: lateral and medial pectoral n.

Question 16

Pectoralis minor m.

Answer 16

Actions: stabilizes scapula by pulling it anteriorly and inferiorly agains posterior thoracic wall

Blood supply: pectoral branch(es) of thoracoacromial arterial trunk

Inn: medial pectoral n. (usually pierced by this nerve)

Question 17

Subclavius m.

Answer 17

Actions: anchors and depresses clavicle

Blood supply: clavicular branch(es) of thoracoacromial arterial trunk

Inn: nerve to subclavius (C5,C6)

Question 18

Serratus anterior m.

Answer 18

Actions: protracts scapula, rotates scapula, holds scapula agains thorax

Blood supply: latera thoracic a.

Inn: long thoracic n.

Question 19

Axillary a. Pt. 1

Answer 19

superior thoracic a.

Question 20

Axillary a. Pt. 2 - Throacoacromial trunk

Answer 20

pectoral branch
deltoid branch
acromial branch
clavicular branch

Question 21

Axillary a. Pt. 3 - distal/lateral to P. minor

Answer 21

subscapular a. (circumflex scapular and thoracoodorsal)
anterior circumflex humeral
posterior circumflex humeral

Question 22

Venous Drainage - Pectoral Region

Answer 22

drained by axillary vein

Question 23

Axillary vein

Answer 23

deep brachial veins

superficial veins of arm and forearm (basilic and cephalic veins)

Question 24

Basilic v.

Answer 24

continues as axillary vein

Question 25

Cephalic v.

Answer 25

drains into axillary before it becomes subclavian vein

Question 26

Boundaries of the Axilla

Answer 26

``` a pyramid shaped space apex base (A&P axillary folds) anterior wall posterior wall medial wall lateral wall ```

Question 27

Apex of Axilla

Answer 27

clavicle scapula 1st. rib

Question 28

Base of Axilla

Answer 28

skin and superficial fascia ant. axillary fold - pectoralis major post. axillary fold - LATS and teres major chest wall - serratus anterior

Question 29

Anterior Wall of Axilla

Answer 29

clavicle subclavius pectoralis major pectoralis minor

Question 30

Posterior Wall of Axilla

Answer 30

scapula subscapularis latissimus dorsi teres major

Question 31

Lateral Wall of Axilla

Answer 31

intertubercular sulcus tendon of long head biceps coracobrachilalis tendon

Question 32

Axillary sheath

Answer 32

axillary v. axillary a. brachial plexus