Transcript 03-Upper_Limb

UPPER LIMB

Introduction
 Organization
 Function
By: Dr. Mujahid Khan
Introduction
 The
upper limb is a multijointed lever that
is freely movable on the trunk at the
shoulder joint
 At
the distal end of the upper limb is the
prehensile organ, the hand.
Introduction
 Much
of the importance of the hand
depends on the pincerlike action of the
thumb, which enables one to grasp objects
between the thumb and index finger
 The
upper limb is divided into the shoulder
(junction of the trunk with the arm), arm,
elbow, forearm, wrist, and hand.
BREAST
Introduction:
 Breasts
are specialized accessory glands
 Secrete milk
 Present in both sexes
 Similar in males and immature females
Anatomy of Breast
 Has
nipples
 Surrounded
by a colored area of skin
“Areola”
 Consist
of a system of ducts embedded in
connective tissue
At Puberty
 Gradually
enlarge
 Assume
their hemispherical shape under
the influence of ovarian hormones
 The
ducts elongate in size
Extension
 Base
extends from 2nd to the 6th ribs
 From
lateral margin of sternum to
midaxillary line
 Greater
fascia
part of a gland lies in superficial
Axillary Tail
 Extends
upward and laterally
 Pierces
the deep fascia at the lower
border of pectoralis major muscle
 Then
enters the axilla
Formation

Each breast consists of 15-20 lobes which
radiate out from the nipple

The main duct from each lobe opens separately
on the summit of the nipple called Ampulla

Base of nipple is surrounded by AREOLA

Tiny tubercles on the areola produced by the
underlying areolar glands
Fibrous Septa
 Lobes
of the glands are separated by
fibrous septa
 Are
well developed in the upper part of the
gland
 Extend
 Serve
from skin to the deep fascia
as a suspensory ligament
Retromammary Space
These are the connective tissues which
separate the breasts from the deep fascia
covering the underlying muscles
Young & Old
 Breasts
tend to protrude forward from a
circular base in young women
 They
 They
tend to be pendulous in older women
reach their maximum size during
lactation
Early Pregnancy
 In
the early months of pregnancy, there is
a rapid increase in length and branching in
the duct system
 The
secretory alveoli develop at the ends
of the smaller ducts and the connective
tissue becomes filled with expanding and
budding secretory alveoli
Early Pregnancy

The vascularity of the connective tissue also
increases to provide adequate nourishment for
the developing gland

The nipple enlarges, and the areola becomes
darker and more extensive as a result of
increased deposits of melanin pigment in the
epidermis

The areolar glands enlarge and become more
active
Late Pregnancy
 During
the second half of pregnancy, the
growth process slows
 The
breasts continue to enlarge, mostly
because of the distention of the secretory
alveoli with the fluid secretion called
colostrum
Postweaning
 Once
the baby has been weaned, the
breasts return to their inactive state
 The
remaining milk is absorbed, the
secretory alveoli shrink, and most of them
disappear
 The
interlobular connective tissue thickens
Postweaning
 The
breasts and the nipples shrink and
return nearly to their original size
 The
pigmentation of the areola fades, but
the area never lightens to its original color
Postmenopause
 After
the menopause, the breast atrophies
 Most
of the secretory alveoli disappear,
leaving behind the ducts
 The
amount of adipose tissue may
increase or decrease
Postmenopause
 The
breasts tend to shrink in size and
become more pendulous
 The
atrophy after menopause is caused by
an absence of ovarian estrogen and
progesterone
Blood Supply
 Perforating
branches of the internal
thoracic artery and the intercostal arteries
 Axillary
artery via lateral thoracic and
thoracoacromial branches
Lymph Drainage
 Important
clinically because of frequent
development of a cancer
 Subsequent
dissemination of the
malignant cells along the lymph vessels to
the lymph nodes
Division
Breast is divided into 4 quadrants for lymph
drainage
The lateral quadrants of the breast drain into
the anterior axillary or pectoral group of
lymph nodes
The medial quadrants drain by means of
vessels that pierce the intercostal spaces
and enter the internal thoracic group of
nodes