Download Axilla

It is a four sided pyramidal space between root of arm and chest
wall. It allows the passage of the nerves and blood vessels from
neck to upper limb. It has a base, apex and four walls. The base
is directed downwards and is formed by the axillary fascia. The
apex is directed upwards posterior to the clavicle.
The boundaries of the
apex of the axilla are:
Anteriorly; the clavicle.
Posteriorly: the superior
border of the scapula.
Medially: the outer
Border of 1st rib.
Anterior wall is formed by the pectoralis
major and minor muscles, clavipectoral
fascia and subclavius muscle.
The lower border of the anterior wall is called
the anterior fold of the axilla (pectoralis major
muscle).
Posterior wall is formed by the
subscapularis muscle above and the
latissimus dorsi and teres major muscles
below.
The lower border of the posterior wall is
called the posterior fold of the axilla
(latissimus dorsi and teres major muscles).
Medial wall is formed of the thoracic wall
with the serratus anterior muscle.
Lateral wall is narrow and formed by the
upper pert of the shaft of the humerus.
1.
2.
3.
4.
5.
6.
7.
Axillary artery and
branches.
Axillary vein and
tributaries.
Brachial plexus (cords
and branches).
Axillary lymph nodes.
Lateral cutaneous
branches of intercostal
nerves.
Axillary fat.
Axillary tail of breast.
Beginning
It begins as a
continuation of the
subclavian artery at
outer border of 1st rib.
Termination
It ends at the lower
border of teres major
and continues as
brachial artery.
Parts
The artery is divided
into 3 parts by pectoralis
minor muscle.
st
1 part:
st
From lateral border of 1
rib to upper border of
pectoralis minor
nd
2 part:
Behind pectoralis minor
rd
3 part:
From lower border of
pectoralis minor to lower
border of teres major
From the 1st Part:
Superior thoracic artery.
From the 2nd Part:
1. Thoracoacromial artery.
2. Lateral thoracic artery.
From the 3rd Part:
1. Subscapular artery
2. Anterior circumflex humeral
artery.
3. Posterior circumflex humeral
artery.
Axillary lymph nodes are
arranged in the following
groups:
Anterior (pectoral) axillary
lymph nodes.
Posterior (subscapular)
axillary lymph nodes.
Lateral (brachial) lymph
nodes.
Central lymph nodes.
Apical lymph nodes.
Anterior nodes
The anterior nodes (pectoral nodes)
are related to the lateral thoracic
artery.
Posterior nodes
The posterior nodes (subscapular
nodes) lie on the lower margin of the
posterior wall of the axilla, along the
course of the subscapular artery.
Lateral nodes
The lateral nodes lie along the lateral
wall of the axilla.
Central nodes
The central nodes are a group of
nodes in the adipose tissue at the base
of the axilla.
Apical nodes
The apical nodes are present in the
apex of the axilla.
It is the plexus of spinal nerves
supplying the upper limb.
1- Roots:
It takes origin in the neck from:
The ventral rami of the lower 4 cervical
nerves (C.5,6,7,8).
The ventral ramus of first thoracic
nerve (T1).
2- Trunks:
Upper trunk, middle trunk & lower
trunk.
3- Divisions:
Each trunk divides into 2 divisions:
anterior and posterior division.
4- Cords:
Lateral cord (anterior divisions of the
upper and middle trunks; C.5,6,7).
Medial cord (anterior division of the
lower trunk only; C.8, T.1).
Posterior cord (posterior divisions of
the 3 trunks; C.5,6,7,8, T.1).
Position of the plexus:
Roots & trunks: are present in
the posterior triangle of the
neck.
Divisions: are present behind
the clavicle.
Cords: are present in the axilla.
Branches of the plexus:
Branches from the roots:
Dorsal scapular nerve.
Long thoracic nerve.
Branches from the trunk:
Suprascapular nerve.
Nerve to subclavius.
Medial cord:
Medial Cutaneous nerve of the arm.
Medial Cutaneous nerve of the
forearm.
Medial pectoral nerve.
Medial root of median nerve.
Ulnar nerve.
Lateral cord:
Lateral pectoral nerve
Lateral root of median nerve.
Musculocutaneous nerve.
Posterior cord:
Upper subscapular nerve.
Lower subscapular nerve.
Nerve to latissmus dorsi.
Axillary nerve.
Radial nerve.
Prof.: Dr. Wafaa Abdel-Rahman