1. The document describes the anatomy of the pectoral region including bones like the clavicle and scapula, and muscles that connect the upper limb to the thoracic wall and vertebral column. 2. It also describes the anatomy of the breast including its composition of ducts and lobes, blood supply from intercostal and thoracodorsal arteries, and lymphatic drainage to axillary lymph nodes. 3. Key axillary lymph node groups are described including the anterior, posterior, lateral, central, apical, and infraclavicular nodes. Clinical correlations regarding breast cancer spread and surgical incisions are provided.

1. Pectoral Region & Breast
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‫العاني‬ ‫الجواد‬ ‫عبد‬ ‫معتز‬
‫الوالدة‬ ‫وحديثي‬ ‫االطفال‬ ‫جراحة‬ ‫استشاري‬

2. Aims of the lecture
At the end of the lecture the students will be
able to describe:
1.Bones of the pectoral region.
2.Muscles between the pectoral region ,vertebrae,
scapulae and the upper limb.
3.Breast position ,composition, blood supply and lymphatic
drainage with axillary lymph nodes groups.

3. Bones

4. Clavicle

5. Scapula

6. Humerus

7. Muscles
• Muscles Connecting the Upper Limb to The Thoracic
Wall.
(Pectoralis major, minor, Subclavius, Serratus anterior)

8. Pectoralis Major
Origin : 3 heads;
•Clavicular head: From;
Medial ½ of the front of the
clavicle.
•Sternocostal head: From;
Sternum.
Upper 6 costal cartilages.
. Abdominal head from
Aponeurosis of the external
oblique muscle.
Insertion :
Lateral lip of bicipital groove.
Nerve supply :
Medial & lateral pectoral N.
Action :
•Adduction and medial rotation of
the arm.
•Clavicular head helps in flexion of
arm (shoulder).

9. Pectoralis Minor
Origin:
• From 3rd ,4th, & 5th ribs close
to their costal cartilages.
Insertion:
Coracoid process.
Nerve supply:
Medial pectoral nerve.
Action:
• Depression of the shoulder.
• Draw the ribs upward and
outwards during deep
inspiration.
3
4
5

10. Thoracic Outlet Syndrome

11. Subclavius
Origin:
• From 1st rib at its costal
cartilage.
Insertion:
• Subclavian groove in the
middle 1/3 of the inferior
surface of clavicle.
Nerve supply:
• Nerve to subclavius from
upper trunk of brachial
plexus.
Action:
• Fixes the clavicle during
movement of shoulder
joint.

12. Clavipectoral Fascia
• It is a thickened membrane of deep fascia between the subclavius
and pectoralis minor.
• It Is Pierced By :
 Lateral pectoral nerve.
 Thoraco- acromial artery
 Cephalic vein.
 Few lymph vessels.

13. Origin:
• Upper eight ribs.
Insertion:
• Anterior aspect of the
medial border and
inferior angle of scapula.
Nerve supply:
Long thoracic nerve.
Action:
• Draws the scapula
forward in boxing,
(protrusion).
• Rotates scapula
outwards in raising the
arm above 90 degree.
Serratus anterior

14. ( Trapezius , Latissimus dorsi , Rhomboid major ,Rhomboid Minor )
Muscles Connecting the Upper Limb
to the Vertebral Column.

16. (Deltoid ,Supraspinatus ,infraspinatus ,
Teres major, minor, Subscapularis)
Muscles Connecting the Upper Limb
to the Scapula

18. The Breast

19. The Breasts
 The breasts are specialized
accessory glands of the skin
that secrete milk and present in
both sexes.
 The nipples are small and
surrounded by a colored area of
skin called the areola.
 The breast tissue consists of a
system of ducts embedded in
connective tissue .

20. The base of the breast extends from the 2nd to 6th rib and from the
lateral margin of the sternum to the midaxillary line.
The greater part of the gland lies in the superficial fascia. A small
part, called the axillary tail extends upward and laterally, pierces
the deep fascia at the lower border of the pectoralis major muscle,
and enters the axilla.

21. Each breast consists of 15 to 20
lobes, which radiate out from the
nipple.
The main duct from each lobe
opens separately on the nipple
and possesses a dilated ampulla
just before its termination.
The lobes of the gland are
separated by fibrous septa that
serve as suspensory ligaments .
Behind the breasts is a space
filled by loose connective tissue
called the retromammary space

22. Blood supply of the Breast
1.The internal thoracic A.
( perforating branches)
2.The intercostal A.
3.The axillary A. via its
lateral thoracic and
thoracoacromial branches.

23. The lateral quadrants of the breast
drain into :
The anterior axillary or pectoral
group of nodes (situated posterior to
the lower border of the pectoralis
minor muscle and the superior
border of the pectoralis major
muscle.
Lymphatic Drainage of The Breast

24. The medial quadrants drain to the
internal thoracic group of nodes . (by
means of vessels that pierce the
intercostal spaces )
A few lymph vessels follow the posterior
intercostal arteries and drain posteriorly
into the posterior intercostal nodes.
Some vessels communicate with the
lymph vessels of the opposite breast.
Lymphatic Drainage of The Breast

25. Axillary lymph nodes
The axillary lymph nodes (20 to 30 in number) drain lymph
vessels from:
1.Lateral quadrants of the breast.
2.Superficial lymph vessels from the thoracoabdominal walls above the
level of the umbilicus.
3.Vessels from the upper limb.

26. 1. Anterior (Pectoral) Group: Lying along the lower
border of the pectoralis minor, these nodes receive lymph
vessels from the lateral quadrants of the breast and
superficial vessels from the anterolateral abdominal wall
above the level of the umbilicus.

27. 2. Posterior (Subscapular) Group: Lying in front of
the subscapularis muscle, these nodes receive
superficial lymph vessels from the back, down as far as
the level of the iliac crests.

28. 3.Lateral Group: Lying along the medial side of the
axillary vein, these nodes receive most of the lymph
vessels of the upper limb
4.Central Group: Lying in the center of the axilla in the
axillary fat, these nodes receive lymph from the above
three groups.

29. 5. Apical Group: Lying at the apex of the axilla at the
lateral border of the 1st rib, these nodes receive the
efferent lymph vessels from all the other axillary nodes.

30. 6.Infraclavicular (Deltopectoral) Group:
These nodes are not strictly axillary nodes because they
are located outside the axilla. They lie in the groove
between the deltoid and pectoralis major muscles and
receive superficial lymph vessels from the lateral side of
the hand, forearm, and arm.

31. Applied Anatomy
Breast cancer – most common form of Ca in women
Spreads via lymphatics, vascular channels & fibrous tissue
Incisions – radial as ducts maintain a radial course
Cyst (galactocole) – may develop with blockade of a
lactiferous duct

32. Applied Anatomy
Peau D’ orange :Pits of hair follicles appear to be
retracted beneath level of surrounding skin blockage of
lymphatic drainage of skin, leading to stagnation of lymph &
oedema of skin.
Retraction of Nipple :Extension of growth along milk line
ducts with subsequent retraction as fibrosis occurs leading
to indrawn nipple.

33. Applied Anatomy
• Polymastia (1 or 2 mammae) or
• polythelia (1 or more nipples) May occur in males or females
usually along a line extending from axilla to pubic region (milk line )
• Amastia , Absence of breast on one or both sides.