The document summarizes the anatomy of the pectoral region and breast. It describes the muscles of the pectoral region including the pectoralis major and minor, serratus anterior, and subclavius. It outlines the structures and blood supply of the breast as well as its lymphatic drainage pathways. The breast is described as consisting of glandular tissue, connective stroma, skin, nipple, and areola. Lymph from the breast drains initially into subareolar nodes and then to axillary and other regional nodes.

1. PECTORAL REGION AND
BREAST
In the name of Allah the compassionate the merciful
Dr. Motaz Ahmed NuggedAlla
Head Department of AnatomyMS.c AAU
PhD UoG

2. Objectives:
1. The muscles of
the pectoral
region, their
action and
innervation.
2. The structures
of the breast

3. (A) Pectoral region
Is external to the anterior thoracic wall
• Provides support for the upper
limb.
• Superficial compartment contains skin,
fasciae & breast.
• Deep compartment contains
muscles.

4. Topographical Anatomy
 midaxillary line.
 midclavicular line.
 deltopectoral triangle.
 Nipple.
 Areola.
 suprasternal notch.
 Anterior axillary fold.
 Epigastric pit.
 Sternal angle.
 Digitations of serattus anterior.

5. Topographical Anatomy of the pectoral region

6. deltopectoral triangle
deltopectoral triangle
Midaxillary & midclavicular lines

7. Osteology of the Pectoral
Region
 Clavicle:
 Ribs:
 Sternum:
 Scapula:
 Humerus:

8. CLAVICLE
THORACIC CAGE,RIBS

9. Sternum

10. Scapula
Humerus

11. Muscles of
pectoral region
a. Pectoralis Major
b. Pectoralis Minor
c. Serratus Anterior
d. Subclavious

12. Pectoralis major muscle:
O:Clavicular head: anterior
surface of medial half of
clavicle
Sternocostal head:
anterior surface of
sternum, superior six
costal cartilages.
I:Lateral lip of
intertubercular groove of
humerus.
Nerve supply:Lateral and
medial pectoral nerves

13. Pectoralis minor muscle:
O:3rd to 5th ribs near
their costal cartilages.
I:Medial border and
superior surface of
coracoid process of
scapula.
Nerve supply:Medial
pectoral nerve

14. Subclavius muscle:
O. 1st costal
cartilage
I. inferior
surface of
clavicle
Nerve supply:
Nerve to sub-
clavius

15. Serratus anterior muscle:
O. half way of
the anterior part
of rib 1-8
I. medial border
of the scapula
Nerve supply:
Long thoracic
nerve

16. When the serratus anterior is paralyzed by
injury of the long thoracic nerve. the medial
border of the scapula moves laterally and
posteriorly away from the thoracic wall, giving
the scapula the appearance of a wing, a
deformation known as a winged scapula .

17. winged scapula

18. clavipectoral fascia

19. (B) Breast

20. The breast

21. The breast
 Definition:
The mammary glands are modified sweat
glands
 Position:
In the superficial fascia anterior to the
pectoral muscles and the anterior thoracic
wall.
 Extent:
 Vertically Breast base runs over ribs 2-6.
 Horizontally from the sternum to the Midaxillary line.

23.  Deep relations:
Pectoralis major and Serratus anterior
muscles.
 Retromammary space separate it from
the pectoralis major & Serratus anterior
muscles(allow mobility).

24. Breasts rest on a muscular bed
formed mostly by pectoralis major
& serratus anterior
Breast base runs over costal cartilages
2-6, from the sternum to the
midaxillary line

25. Structure:
1. Parenchyma:
• Glandular tissue which secretes
milk.
• Consist of 15 to 20 lobes.
• Lactiferous ducts converge
towards the nipple.

26. Sagittal section of female breast

27. 2. Stroma (supporting connective
tissue):
• Fatty stroma: forms the main bulk
of the breast.
• Fibrous stroma:
• divides the breast into lobes and
lobules (suspensory ligament).
• Anchors the skin of the breast t the
pectoral fascia.

28. 3. Skin:
• Covers the breast.
• Presents a conical projection
(nipple); which is surround by
pigmented area (areola).
• Innervated by intercostal (2-6)
and supraclavicular nerves.

29. Breast is supplied by the intercostal &
supraclavicular nerves

30. Blood supply of the breast
 Arterial supply:
 laterally, vessels from the axillary artery-
superior thoracic, thoracoacromial, lateral
thoracic, and subscapular arteries.
 medially, branches from the internal thoracic
artery; the second to fourth intercostal
arteries via branches that perforate the
thoracic wall and overlying muscle.
 Venous drainage:
Veins draining the breast parallel the arteries
and ultimately drain into the axillary, internal
thoracic, and intercostal veins.

31. Blood supply of the breast

32. Lymphatic drainage
 Axillary lymph nodes.
 parasternal nodes.
 Posterior intercostal.
 Sub diaphragmatic.

33. Posterior nodes
(subscapular)
Lateral nodes
(humeral)
Central nodes
Apical nodes
Anterior nodes
(pectoral)
UL
Parasternal nodes
Axillary Nodes
Lymphatics of pectoral region

34. Lymphatic drainage of the breast

35. Breasts have several regions of
lymphatic drainage Nipples, areola,
& lobules of the breast drain initially
into a subareolar lymphatic plexus
Lymph flows through multiple
groups of nodes before it reaches
the blood

37. References:
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