AXILLAAXILLA

BoundariesBoundaries

ContentsContents

Axillary VesselsAxillary Vessels

By: Dr. Mujahid KhanBy: Dr. Mujahid Khan

AXILLAAXILLA

DefinitionDefinition

• It is a pyramid shaped space between the It is a pyramid shaped space between the upper part of the arm and the side of the upper part of the arm and the side of the chestchest

• Important Nerves, Blood and Lymph Important Nerves, Blood and Lymph vessels travel through it from root of the vessels travel through it from root of the neck to the upper limbneck to the upper limb

ApexApex

• Upper end of axilla or APEX is directed Upper end of axilla or APEX is directed into the root of neckinto the root of neck

• Bounded in front by the clavicleBounded in front by the clavicle

• Behind by the upper border of scapulaBehind by the upper border of scapula

• Medially by outer border of the 1Medially by outer border of the 1stst rib rib

BaseBase• Lower end or Base is bounded in front by Lower end or Base is bounded in front by

the anterior axillary fold formed by the anterior axillary fold formed by pectoralis major musclepectoralis major muscle

• Behind by posterior axillary fold formed by Behind by posterior axillary fold formed by the tendons of latissimus dorsi and teres the tendons of latissimus dorsi and teres major musclesmajor muscles

• Medially by the chest wallMedially by the chest wall

Walls of The AxillaWalls of The Axilla

• Anterior wall:Anterior wall:

By the pectoralis major, Subclavius and By the pectoralis major, Subclavius and pectoralis minor musclespectoralis minor muscles

• Posterior wall:Posterior wall:

By the subscapularis, Latissimus dorsi and By the subscapularis, Latissimus dorsi and teres major musclesteres major muscles

Walls of The AxillaWalls of The Axilla

• Medial wall:Medial wall:

By the upper 4 or 5 ribs and intercostal By the upper 4 or 5 ribs and intercostal spaces covered by serratus anterior spaces covered by serratus anterior musclemuscle

• Lateral wall:Lateral wall:

By the coracobrachialis and biceps By the coracobrachialis and biceps muscles in the bicipital groove of humerusmuscles in the bicipital groove of humerus

BaseBase

• The Base of axilla is formed by the skin The Base of axilla is formed by the skin

stretching between the anterior andstretching between the anterior and

posterior wallsposterior walls

• The axilla contains the principal vessels The axilla contains the principal vessels and nerves to the upper limb and many and nerves to the upper limb and many lymph nodeslymph nodes

Clavipectoral FasciaClavipectoral Fascia

• It is a strong sheet of connective tissueIt is a strong sheet of connective tissue• Splits above to enclose the subclavius Splits above to enclose the subclavius

muscle and is attached to the claviclemuscle and is attached to the clavicle• Below it splits to enclose the pectoralis Below it splits to enclose the pectoralis

minor muscleminor muscle• Then continues downward as the Then continues downward as the

suspensory ligament of the axillasuspensory ligament of the axilla• Then joins the fascial floor of armpitThen joins the fascial floor of armpit

Contents of AxillaContents of Axilla

• Axillary artery and its branchesAxillary artery and its branches

• Axillary vein and its tributariesAxillary vein and its tributaries

• Lymph vessels and lymph nodesLymph vessels and lymph nodes

• Important nerve plexus the “Brachial Important nerve plexus the “Brachial Plexus” which innervates the upper limbPlexus” which innervates the upper limb

Axillary ArteryAxillary Artery• Is a continuation of subclavian arteryIs a continuation of subclavian artery• Begins at the lateral border of the 1Begins at the lateral border of the 1stst rib rib• Ends at the lower border of teres majorEnds at the lower border of teres major• It continues as the brachial arteryIt continues as the brachial artery• Closely related to brachial plexus cordsClosely related to brachial plexus cords• Enclosed with them in the axillary sheathEnclosed with them in the axillary sheath• Axillary sheath is continuous with the Axillary sheath is continuous with the

prevertebral fasciaprevertebral fascia• Pectoralis minor divides it into 3 partsPectoralis minor divides it into 3 parts

11stst Part of Axillary Artery Part of Axillary Artery

• Extends from the lateral border of the 1Extends from the lateral border of the 1stst

rib to the upper border of pectoralis minor rib to the upper border of pectoralis minor

RelationRelation

• Anterior: Pectoralis major, covering fascia, Anterior: Pectoralis major, covering fascia, skin, cephalic veinskin, cephalic vein

• Posterior: Long thoracic nervePosterior: Long thoracic nerve

• Lateral: Three cords of brachial plexusLateral: Three cords of brachial plexus

• Medial: Axillary veinMedial: Axillary vein

22ndnd Part of Axillary Artery Part of Axillary Artery

• Lies behind the pectoralis minor muscleLies behind the pectoralis minor muscle

RelationRelation

• Anterior: Pectoralis minor and major, Anterior: Pectoralis minor and major, covering fascia and skincovering fascia and skin

• Posterior: Posterior cord of brachial plexusPosterior: Posterior cord of brachial plexus

• Lateral: Lateral cord of brachial plexusLateral: Lateral cord of brachial plexus

• Medial: Medial cord of brachial plexus and Medial: Medial cord of brachial plexus and axillary veinaxillary vein

33rdrd Part of Axillary Artery Part of Axillary Artery• Extends from lower border of pectoralis Extends from lower border of pectoralis

minor to the lower border of teres majorminor to the lower border of teres major

RelationRelation• Anterior: Pectoralis major, medial root of Anterior: Pectoralis major, medial root of

the median nervethe median nerve

• Posterior: subscapularis, latissimus dorsi Posterior: subscapularis, latissimus dorsi and teres majorand teres major

• Lateral: Coracobrachialis, biceps, humerusLateral: Coracobrachialis, biceps, humerus

• Medial: Ulnar nerve, axillary vein, medial Medial: Ulnar nerve, axillary vein, medial cutaneous nerve of the armcutaneous nerve of the arm

BranchesBranches• Branches of axillary artery supply the Branches of axillary artery supply the

thoracic wall and the shoulder regionthoracic wall and the shoulder region

• 11stst Part: Highest thoracic artery Part: Highest thoracic artery

• 22ndnd Part: Thoracoacromial and lateral Part: Thoracoacromial and lateral thoracic arteriesthoracic arteries

• 33rdrd Part: Subscapular artery, anterior and Part: Subscapular artery, anterior and posterior circumflex humeral arteriesposterior circumflex humeral arteries

Pectoralis MajorPectoralis Major• Origin: Medial half of clavicle, sternum, Origin: Medial half of clavicle, sternum,

upper 6 costal cartilagesupper 6 costal cartilages• Insertion: Lateral lip of bicipital groove of Insertion: Lateral lip of bicipital groove of

the humerus the humerus • NS: Medial and Lateral pectoral nerves NS: Medial and Lateral pectoral nerves

from medial and lateral pectoral cords of from medial and lateral pectoral cords of brachial plexusbrachial plexus

• Action: Adducts the arm and rotates it Action: Adducts the arm and rotates it medially, some fibers also cause flexion of medially, some fibers also cause flexion of armarm

SubclaviusSubclavius• Origin: From the first costal cartilageOrigin: From the first costal cartilage

• Insertion: Fibers move upward and Insertion: Fibers move upward and laterally into the inferior surface of claviclelaterally into the inferior surface of clavicle

• NS: Nerve to the subclavius from upper NS: Nerve to the subclavius from upper trunk of brachial plexustrunk of brachial plexus

• Action: Depresses the clavicle and Action: Depresses the clavicle and steadies this bone during movements of steadies this bone during movements of shoulder girdleshoulder girdle

Pectoralis MinorPectoralis Minor

• Origin: From 3Origin: From 3rdrd, 4, 4thth and 5 and 5thth ribs ribs

• Insertion: Coracoid process of scapulaInsertion: Coracoid process of scapula

• NS: Medial pectoral nerve, a branch of the NS: Medial pectoral nerve, a branch of the medial cord of brachial plexusmedial cord of brachial plexus

• Action: Depresses point of shoulder if the Action: Depresses point of shoulder if the scapula is fixed. Elevates the ribs of originscapula is fixed. Elevates the ribs of origin

SubscapularisSubscapularis• Origin: Subscapular fossa on the anterior Origin: Subscapular fossa on the anterior

surface of scapulasurface of scapula

• Insertion: On the lesser tuberosity of the Insertion: On the lesser tuberosity of the humerushumerus

• NS: Upper and Lower subscapular nervesNS: Upper and Lower subscapular nerves

• Action: Medially rotates the arm and Action: Medially rotates the arm and stabilizes the shoulder jointstabilizes the shoulder joint

Latissimus DorsiLatissimus Dorsi• Origin: Posterior part of the iliac crest, lumbar Origin: Posterior part of the iliac crest, lumbar

fascia and spines of lower 6 thoracic vertebrae, fascia and spines of lower 6 thoracic vertebrae, lower 3 or 4 ribs and inferior angle of scapulalower 3 or 4 ribs and inferior angle of scapula

• Insertion: Floor of the bicipital groove of Insertion: Floor of the bicipital groove of humerus with teres majorhumerus with teres major

• NS: Thoracodorsal nerve from posterior cord of NS: Thoracodorsal nerve from posterior cord of brachial plexusbrachial plexus

• Action: Extends, adducts and medially rotates Action: Extends, adducts and medially rotates the armthe arm

Teres MajorTeres Major• Origin: lower third of the lateral border of Origin: lower third of the lateral border of

scapulascapula

• Insertion: Medial lip of bicipital groove of Insertion: Medial lip of bicipital groove of humerushumerus

• NS: Lower subscapular nerve from NS: Lower subscapular nerve from posterior cord of brachial plexusposterior cord of brachial plexus

• Action: Adducts and medially rotates the Action: Adducts and medially rotates the arm and stabilizes shoulder jointarm and stabilizes shoulder joint

Serratus AnteriorSerratus Anterior

• Origin: From Outer surface of upper 8 ribsOrigin: From Outer surface of upper 8 ribs

• Insertion: Medial border and inferior angle Insertion: Medial border and inferior angle of scapulaof scapula

• NS: Long thoracic nerveNS: Long thoracic nerve

• Action: Draws the scapula forward around Action: Draws the scapula forward around the thoracic wall and rotates itthe thoracic wall and rotates it