Axilla - Complete Lecture Notes

AXILLADEPINATIONThe axilla or armpit is a fat filled, hollowed outpyramidal Shaped space- between the upper partof the arm and the side of the chest wall. It containsbrachial plaxs, axillary vessels and lymph nodes and acts alsoas a funnel shaped tunnel for neurovascular Structures to passfrom the voot of neck to upper limb and vice versa.SITE: It lies obliquely between the upper part of the arm andthe upper part of the side of the chest. It is situatedjust above the armpit.DIPANKAR RAYSHADE:It is pyramidal in shape, having apex, base and 4 walls-Anterior, Posterior, Medial and lateral.APEX OF AXILLA:Human Anatomy For Exam.It lies in the upper part and is directed upwards and medially.It connects the axilla with the post triangle of the neck(it is called the Cerricoaxillary Canal)It is narrow and triangular in outline and is bounded by(i) The middle 1/3 of the clavicleAnteriorly.(ii) The upper border of scaptulas(iii) The outer border of 1st RibPosteriorly.It Brachial transmits the axillary vessels and cords ofMedially,BASE (FLOOR) OF AXILLA :plexus from the root of the trunk to the the axilla.It Farms is formed lower wall the of axilla and is directed downwards and laterallyThe by fascia is skin and fascia of the armpit (Axillary fascia).pectoralis minor by the suspensary ligament of axilla.axillary connected above to the lower border ofLATERAL WALLIt is and the muscles.- narrowest wall and is formed of the following bure(iii) Corasobrachiolis.Muce(i) Upper part of Humerus (ii) Short Head of Biceps Muscle.The main vessels and nerves of the axilla are related tolateral wall. AXILLA2MEDIAL WALLFormed of the following bones and muscles.-(i) THE UPPER 4 or 5 Ribs,(ii) THE INTERCOSTAL MUSCLES between the ribs.(iii) THE Upper part of Serratus Anterior Muscle.ANTERIOR WALLConsists of layers- DIMAVIAR RAY21SUPERFICIAL LAYER :- Formed by Pectoralis Major Muscle.2DEEP LAYER:- Formed by the following 3 Structures.(i) Subclavies Muscle(ii) Claripectacal fasciaArranged from(iii) Pectoralis minorAboveDownwardsPOSTERIOR WALLIt is longers wider than the centerior wall.It is formed of the following 3 muscles1 Subscapularis M. (Filling the subscapular fossa)2 Teres major M.3Latissimus dorsi M,lying along the lateral border of the scapula.AXILLARY FOLDSHuman Anatomy For Exam .ANT-AXILLARY FOLD: It is the lower border of anterior wall ofaxilla and is formed by the lower borderof Pecturalis Major M. woneIts downward continuation is called Anterior Axillary line.POST AXILLARY FOLD: It is the lower border of post wall ofAxillaIt's formed by both Teres major & Lattisimus dorsi muscles andit extends lower down than the anterior axillary foldA line drawn as a downward continuation of posterior fold iscalled the Posterior Axillary line..The Mid-axillary line lies midway between the anterior andposterior axillary lines. AXILLA3CONTENTS OF THE AXILLAItis filled with axillary fat and contains the followingStructures:-AXILLARY AR & ITS BRANCHESIt enters the axilla through its apex then runs along thelateral wall to end at the lower border of Teres major m.by becoming the brachial artery.It gives 6 branches in the axillaAXILLARY VEIN & ITS BRANCHESDRANNAR RAYIt enters the axilla from below ( At lower border of Teres major)then runs upwards along the medial side of the axillaryartery It leaves the axilla at its apex by becoming theSubclavian Vein.BRACHIAL PLEXUS : CORDS & BRANCHES Arranged around the Axillary ATas follows-aMedial Cord lies behind the 1st part of the artery then medial to its2nd part. Its branches lie med to 3rd part.bLateral card lies Lateral the 1st & 2nd part of artery and its brancheslie lat to the 3rd part of artery .CPosterior and its Cord lies Lateral to the 1st part then posterior to th 2nd partbranches lie posterior to the 3rd part of arteryAXILLARY LYMPH NODESArranged in 5 groups in relation to the walls and apexAXILLARY TAIL OF FEMALE BREASTAn upward extension of the mammary gland to the axilla.Nerve to Serratus Anterior:- Descends vertically on the medial wallof axilla in midaxillary line.Intercostobrachial Neme:- It is the lateral cuteneou Dr. of T2 Nervewhich crases the axilla to supply its floor