2 - Aldridge - Pectoral Region / Axilla Flashcards
Mammary Gland
Modified sweat gland that secretes Milk
Ducts/secretory units well developed in post-puberty females; males contain structures but not well developed
Retromammary Space
Potential space between gland and deep fascia of pectoralis major; allows for some movement of breast
Suspensory Ligaments (of Cooper)
Fibrous bands that attach the breast to the overlying skin
Act as walls which divide breast into fat-filled lobes (contain milk glands)
Carcinoma creates tension in these, causing pitting of the skin
Axillary Tail (of Spence)
Small part of the fland that extends superio-laterally into the armpit (axilla)
Lobes (of Breast)
Divide breast into 15-20 compartments, each separated by suspensory ligaments
Contains fat, glandular tissue, and lactiferous ducts
Nipples
Surrounded by areola, lactiferous duct from each lobe empties at the nipple
Arterial supply for breast?
Perforating Branches and Anterior Intercostal Branches of Internal Thoracic Artery
Lateral Thoracic and Thoracoacromial branches of Axillary Artery
Lymphatic Drainage (of breast)
Lateral quadrants of breast:
Drain into anterior (or pectoral) group
75% to anterior group
- - - -
Medial quadrants of breast:
Drain into parasternal nodes located along internal thoracis vessels of the chest wall or drain to the opposite breast
25% to parasternal nodes
- - -
Lower quadrant of breast:
Can drain inferiorly into abdominal nodes
Serratus Anterior Innervation
Clinical presentation of disruption?
Long Thoracic Nerve (C5, C6, C7)
S.A.L.T.
Serratus Anterior Long Thoracic
- - -
Winged scapula (pushing)
Fascia of Pectoral Region
Invests the four pectoral muscles
- Pectoral Fascia - covers pectoralis major
- Clavipectoral Fascia - encloses pectoral minor and subclavius and attaches to clavicle, protects underlying neurovascular structures that supply upper limb
What structures pierce the clavipectoral fascia?
- Cephalic Vein
- Thoracoacromial Artery
- Lateral Pectoral Nerve
- Medial Pectoral Nerve (on its own)
Clavipectoral/Deltopectoral Triangle
Borders?
Contents?
Borders:
a. Superior - Clavicle
b. Lateral - Deltoid
c. Medial - Pectoralis Major
- - -
Contents:
a. Cephalic Vein (superficial)
b. Tip of Coracoid Process (deep, can palpate)
Axilla
Pyramidal shaped area between arm and upper thorax
Passageway for the neurovascular supply to the upper limb
Borders of Axilla:
Anterior Wall
Posterior Wall
Medial Wall
Lateral Wall
Floor
Anterior Wall - Pectoralis Major/Minor
Posterior Wall - Scapula, Subcapularis, Latissimus Dorsi, Teres Major
Medial Wall - Upper 4 ribs, intercostal muscles between ribs, serratus anterior
Lateral Wall - Intertubercular Groove of Humerus
Floor - Fascia and dome of skin, supported by suspensory ligament of axilla from clavipectoral fascia
Only major structure that passes directly through medial wall, and into axilla?
Intercostobrachial nerve
= lateral cutaneous branch of the second intercostal nerve
Part of T2 dermatome
Six Parts of Axillary Artery
S T L S A P
Part 1:
(S) - Superior Thoracic Artery
Part 2:
(T) - Thoracoacromial Artery
(L) - Lateral Thoracic Artery
Part 3:
(S) - Subscapular Artery
(A) - Anterior Circumflex Humeral Artery
(P) - Posterior Circumflex Artery
What is the origin of the Axillary artery? What vessel does it originate from?
When does it become the brachial artery?
Originates from the subclavian artery in the neck
Becomes the axillary artery at the lateral margin of the 1st rib and passes through the axilla
Becomes brachial artery at the inferior margin of the teres major muscle
Axillary Vein
Runs medial to the Axillary Artery
Posterior Circumflex Artery
Runs posteriorly with the axillary nerve through the quadrangular space, winds posteriorly around surgical nexk of humerus
Axillary Lymph Nodes
Receive lymph from the upper limb and breast, drain into subclavian lymph trunks which drain into:
Right - Right Lymphatic Duct
Left - Thoracic Duct
