Download The axilla

The axilla
University Of Babylon
College Of Medicine
Department Of Human Anatomy And
Histology
Dr. Haythem Ali Alsayigh
M.B.CH.B. - F.I.M.B.S.
The axilla
Walls
Axillary sheath
Axillary artery
Axillary vein
Scapular
anastomosis
The axilla
Is the space between
the medial part of the
arm and the side of
the chest
The axilla
forms an important
passage for nerves
and vessels from the
neck to the upper
limb
The axilla
It has the shape of a
truncated 3-sided
pyramid
Apex of the axilla
The apex is directed
towards the root of
the neck
it is a narrow
triangular gap which
is bounded by the
clavicle anteriorly,
scapula posteriorly,
and the first rib
medially.
Apex of the axilla
The apex is also
called the inlet since
it allows the entrance
to the axilla of nerves
and vessels
Base of the axilla
The base faces
inferiorly and is
formed by fascia and
skin, the fascia is
supported by the
suspensory
ligament of the
axilla which renders
the base hollow
Base of the axilla
The base faces
inferiorly and is
formed by fascia and
skin, the fascia is
supported by the
suspensory
ligament of the
axilla which renders
the base hollow
Anterior wall of the axilla
Pectoralis
minor
Pectoralis major
This is formed by the
clavicle, pectoralis major,
pectoralis minor,
subclavius, and the
clavipectoral fascia
Posterior wall of the axilla
scapula
subscapularis
Latissimus dorsi
Axillary folds
The anterior and
posterior walls of the
axilla can be palpated
by fingers and thumb
thus forming the
anterior and posterior
axillary folds.
The anterior axillary fold is formed by the
lateral border of pectoralis major
Axillary folds
The posterior axillary
fold is formed by teres
major and latissimus
dorsi
teres
major
latissimus
dorsi
Medial wall of axilla
The medial wall is
formed by the upper
ribs and intercostal
muscles covered by
serratus anterior
muscle
Lateral wall of axilla
 The lateral wall is narrow
and is formed by the
floor of the
intertubercular groove of
the humerus to which is
attached the tendon of
latissimus dorsi and in
which runs the tendon of
the long head of biceps
Contents of the axilla
axillary a.
axillary v.
Fat
brachial
axillary
artery
plexus
axillary vein
brachial
plexus
fat
axillary nodes
axillary lymph
lymph
nodes
Axillary sheath
The vessels and the
brachial plexus are
enclosed in a fascial
sleeve (axillary
sheeth) which is a
downward
prolongation of the
pre-vertebral fascia in
the neck
Axillary sheath
In the neck, the
cervical vertebrae and
the muscles attached
to them are bound
together by a dense
fascial layer called
prevertebral fascia
Axillary sheath
Among the muscles
of the neck are
scalenus anterior and
scalenus medius,
these are attached to
the anterior and
posterior tubercles of
the transverse
process of cervical
vertebrae respectively
Axillary sheath
The roots of the
brachial plexus lie
between these
muscles
The subclavian artery
passes behind
scalenus anterior at
the root of the neck
Axillary sheath
the brachial plexus and the
axillary artery (the continuation
of the subclavian artery), during
their passage from the neck to
the axilla have to pierce the
prevertebral fascia and while
doing so they take a
prolongation of the fascia down
with them in the form of a
sleeve called the "axillary
sheath"
Axillary artery
Begins at the outer
border of the first rib
as the continuation of
the subclavian artery
Axillary artery
Ends by becoming the
brachial artery at the
lower border of teres
major
Axillary artery
For descriptive
purposes it is divided
into three parts by
pectoralis minor
muscle
Axillary artery
The second part is
located behind the
muscle
Axillary artery
the axillary vein is
medial to the artery
Axillary artery
Axillary v.
Medial
cord
Axillary a.
posterior
cord
lateral
cord
the cords of the
brachial plexus are
arranged according to
their names around
the second part of
the axillary artery
Axillary artery
the medial cord is
thus between the
artery and vein
Branches of the axillary artery
1 from the 1st part
2 from the 2nd part
3 from the 3rd part
Branches of the 1st part of the
axillary artery
Superior thoracic
artery
Branches of the 2nd part of the
axillary artery
Thoraco-acromial
artery
Thoraco-acromial artery
This artery is short
and wide, it pierces
the clavipectoral
fascia and is divided
then into four
branches (acromial,
deltoid, pectoral, and
clavicular)
Branches of the 2nd part of the
axillary artery
Thoraco-acromial
artery
lateral thoracic artery
Lateral thoracic artery
The lateral thoracic
artery follows the
lower border of
pectoralis minor
muscle and is
important for the
blood supply of the
female breast.
Branches of the 3rd part of the
axillary artery
Anterior circumflex
humeral artery
posterior circumflex
humeral artery
Branches of the 3rd part of the
axillary artery
Anterior circumflex
humeral artery
posterior circumflex
humeral artery
subscapular artery
Subscapular artery
descends along the
lateral border of the
scapula and ends as
the circumflex
scapular and
thoracodorsal arteries
Circumflex scapular
Thoraco-dorsal
Subscapular artery
the circumflex scapular artery
passes around the lateral border
of the scapula to supply muscles
on the dorsal aspect of the
scapula.
The thoracodorsal artery is the
continuation of the subscapular
artery along the lateral border
of the scapula
Circumflex humeral arteries
the posterior is the
larger
the circumflex
humeral arteries pass
around the surgical
neck of the humerus
to anastomose with
each other
Palpation of the axillary artery
The third part of the
axillary artery can be
palpated in the lateral
wall of the inferior
part of the axilla and
can be compressed
against the humerus
Axillary vein
begins at the lower border of teres
major as the continuation of the
basilic vein
It receives the venae comitantes
of the brachial artery and
tributaries that correspond to the
branches of the axillary artery in
addition to the cephalic vein.
Axillary vein
It becomes the
subclavian vein at the
outer border of the
first rib
Axillary vein
It is located medial to
the axillary artery but
when the arm is
abducted it lies anterior
to the artery hiding it
from vision
Owing to the large size
of the axillary vein and
its exposed position, it is
liable to be injured in
wounds of the axilla
Axillary vein
Injury is dangerous not
only because of severe
hemorrhage but also
because of the risk of air
entering the vessel since
the wall tends to be held
apart by the fibrous
expansions over the
vessel from the
clavipectoral fascia
Axillary vein
for this reason, the
axillary vein is cleared
away to avoid injuring
it in subsequent
dissection
Scapular anastomosis
Several vessels
around the scapula
form a network that
provides collateral
circulation for the
upper limb during
ligation of an injured
axillary or subclavian
artery
Subclavian artery
The subclavian artery
is divided (for
descriptive purposes)
into three parts by
scalenus anterior
muscle
Subclavian artery
The first part lies
medial to scalenus
anterior
one of its branches is
the thyrocervical
trunk
Thyrocervical trunk
From the
thyrocervical trunk
arises the transverse
cervical and
suprascapular
arteries.
Transverse cervical artery
The transverse
cervical has a
descending branch
that runs along the
vertebral border of
the scapula
Suprascapular artery
crosses over the
transverse ligament
of the scapular notch
passes through
supraspinous fossa then
around the lateral border
of the scapular spine
(spino-glenoid notch) to
supply the infraspinous
fossa.
Scapular anastomosis
The subscapular artery
from the third part of the
axillary artery descends
along the lateral border
of the scapula and
provides the circumflex
scapular artery which
enters the infraspinous
fossa.
Scapular anastomosis
The subscapular,
suprascapular, and
descending branch of the
circumflex scapular
arteries anastomose,
thus connecting the first
part of the subclavian
with the third part of the
axillary artery
Scapular anastomosis
Thus the axillary artery
may be ligated between
the thyrocervical trunk
and the subscapular
artery i.e. between the
first part of the
subclavian artery and the
third part of the axillary
artery
Scapular anastomosis
in this case the
circulation of blood in the
subscapular artery is
reversed