Axilla

Gross Anatomy


Axilla


Anatomy Tables for Today's Topic

Arteries of the Axilla
Nerves of the Axilla
Lymphatics of the Axillary Region

Arteries of the Axilla

Artery Source Branches Supply to Notes
anterior circumflex humeral axillary a., 3rd part unnamed muscular branches deltoid m.; arm muscles near the surgical neck of the humerus anterior circumflex humeral a. anastomoses with the posterior circumflex humeral a.
axillary subclavian a. (axillary a. is the continuation of the subclavian lateral to the 1st rib) 1st part: superior thoracic a.; 2nd part: thoracoacromial a., lateral thoracic a.; 3rd part: anterior circumflex humeral a., posterior circumflex humeral a., subscapular a. pectoral region, shoulder region and upper limb pectoralis minor m. crosses anterior to the axillary artery and is used to delineate the 3 parts mentioned at left
circumflex scapular subscapular a. unnamed muscular branches teres major m., teres minor m., infraspinatus m. circumflex scapular a. anastomoses with the suprascapular a. and the dorsal scapular a. to form the scapular anastomosis
lateral thoracic axillary, 2nd part unnamed muscular branches serratus anterior m., parts of adjacent muscles, skin and fascia of the anterolateral thoracic wall lateral thoracic a. is a rare case of a muscular artery that enters the muscle (serratus anterior) from its superficial surface
posterior circumflex humeral axillary a., 3rd part unnamed muscular branches deltoid; arm muscles near the surgical neck of the humerus posterior circumflex humeral a. anastomoses with the anterior circumflex humeral a.; it passes through the quadrangular space with the axillary nerve
subscapular axillary a., 3rd part circumflex scapular a., thoracodorsal a. subscapularis m., teres major m., teres minor m., infraspinatus m., latissimus dorsi m. the circumflex scapular branch of the subscapular a. anastomoses with the suprascapular a. and the dorsal scapular a. in the scapular anastomosis
superior thoracic axillary a., 1st part unnamed muscular branches muscles of intercostal spaces 1 and 2 superior thoracic a. anastomoses with the posterior intercostal aa. for intercostal spaces 1 and 2
thoracoacromial axillary a., 2nd part pectoral br., clavicular br., acromial br., deltoid br. pectoralis major m., pectoralis minor m., subclavius m., deltoid m., shoulder joint thoracoacromial trunk pierces the costocoracoid membrane
thoracodorsal subscapular a. unnamed muscular branches latissimus dorsi m. thoracodorsal a. accompanies the thoracodorsal n.


Nerves of the Axilla

Nerve Source Branches Motor Sensory Notes
axillary n. posterior cord of the brachial plexus superior lateral brachial cutaneous nerve deltoid, teres minor skin of the upper lateral arm axillary n. is endangered by fractures of the surgical neck of the humerus
brachial plexus ventral primary rami of spinal nerves C5-8 and T1 dorsal scapular, long thoracic, n. to subclavius, suprascapular, lateral and medial pectoral, medial brachial and antebrachial cutaneous, upper, middle and lower subscapular, musculocutaneous, ulnar, median, axillary, radial muscles of the upper limb, excluding trapezius skin of the upper limb plexus is a latin word meaning "braid"; axons from spinal cord levels C5-T1 are mixed (braided) in the brachial plexus and repackaged into terminal branches so that each branch contains axons from several spinal cord segmental levels
dorsal scapular n. brachial plexus (br. of C5 ventral primary ramus) no named branches rhomboideus major and minor mm.; levator scapulae m. none dorsal scapular n. passes through the scalenus medius m.
long thoracic n. brachial plexus (ventral primary rami of spinal nerves C5-C7) no named branches serratus anterior m. no cutaneous branches located on the superficial surface of the serratus anterior m.; lesion of this nerve causes winged scapula
medial antebrachial cutaneous n. medial cord of the brachial plexus no named branches none skin of the medial side of the forearm medial antebrachial cutaneous nerve travels with the basilic vein for part of its course; also known as: medial cutaneous nerve of the forearm
medial brachial cutaneous n. medial cord of the brachial plexus no named branches none skin of the medial side of the arm communicates with the intercostobrachial n.; also known as: medial cutaneous nerve of the arm
median n. lateral and medial cords of the brachial plexus anterior interosseous n., palmar br., recurrent (motor) br., common palmar digital nn. (for digits 1-3) pronator teres m., flexor carpi radialis m., palmaris longus m., flexor digitorum superficialis m., flexor digitorum profundus m. (radial half), flexor pollicis longus m., pronator quadratus m., abductor pollicis brevis m., flexor pollicis brevis m., opponens pollicis m., lateral 2 lumbrical mm. skin of the radial half of the palm and palmar side of the lateral 3 1/2 digits (and nail bed for these digits) the median n. is motor to the flexor muscles of the forearm (except flexor carpi ulnaris and the medial 1/2 of the flexor digitorum profundus),the muscles of the thenar compartment and the lateral 2 lumbricals
musculocutaneous n. lateral cord of the brachial plexus lateral antebrachial cutaneous n. coracobrachialis m., biceps brachii m., brachialis m. skin of the lateral side of the forearm musculocutaneous n. passes through the coracobrachialis m.
pectoral, lateral lateral cord of the brachial plexus no named branches pectoralis major m. no cutaneous branches lateral pectoral n. communicates with the medial pectoral n. anterior to the axillary a.; it pierces the clavipectoral fascia
pectoral, medial medial cord of the brachial plexus no named branches pectoralis minor m., pectoralis major m. no cutaneous branches medial pectoral n. communicates with the lateral pectoral n. anterior to the axillary a.; it pierces the pectoralis minor m.
radial n. posterior cord of the brachial plexus posterior brachial cutaneous n., inferior lateral brachial cutaneous n., posterior antebrachial cutaneous n., superficial and deep brs. muscles of the posterior arm: triceps brachii m., anconeus m.; muscles of the posterior forearm: brachioradialis, extensor carpi ulnaris m., extensor carpi radialis longus m., extensor carpi radialis brevis m., extensor digitorum m., extensor digiti minimi m., supinator m., abductor pollicis longus m., extensor pollicis longus m., extensor pollicis brevis m., extensor indicis m. skin of the posterior arm, forearm and hand all of the muscles on the posterior side of the arm and forearm are innervated by the radial n.
subclavius m., n. to superior trunk of the brachial plexus no named branches subclavius m. no cutaneous branches nerve to subclavius m. is one of two nerves to arise from the superior trunk of the brachial plexus; suprascapular n. is the other one
subscapular, lower posterior cord of the brachial plexus (C5, C6) unnamed muscular brs. subscapularis m., teres major m. no cutaneous branches subscapularis and teres minor are antagonists (medial rotation vs. lateral rotation of the humerus)
subscapular, middle posterior cord of the brachial plexus (C7, C8) unnamed muscular brs. latissimus dorsi m. no cutaneous branches also called the thoracodorsal n.
subscapular, upper posterior cord of the brachial plexus (C5, C6) unnamed muscular brs. subscapularis m. no cutaneous branches subscapularis is a strong medial rotator of the humerus
suprascapular n. superior trunk of the brachial plexus (C5-C6) no named branches supraspinatus m., infraspinatus m. no cutaneous branches suprascapular n. passes through the scapular notch inferior to the superior transverse scapular ligament
ulnar n. medial cord of the brachial plexus (C8, T1) palmar cutaneous br., dorsal br., superficial and deep brs. flexor carpi ulnaris m., flexor digitorum profundus m. (ulnar half), abductor digiti minimi m., flexor digiti minimi brevis m., opponens digiti minimi m., ulnar 2 lumbrical mm., palmar and dorsal interosseous mm. skin of the medial side of the wrist and hand; skin of the medial 1 1/2 digits ulnar n. is motor to most of the muscles of the hand


Lymphatics of the Axillary Region

Structure Location Afferents from Efferents to Regions drained Notes
axillary nodes axilla cubital nodes; lymphatic vessels from the upper limb, thoracic wall including the breast, subscapular region efferents vessels form the subclavian trunk, some drainage to inferior deep cervical nodes upper limb, most of the mammary gland, some of the anterolateral chest wall, posterior thoracic wall and scapular region axillary nodes number from 20 to 30 and are organized in five groups based on their position within the axilla: 1) pectoral nodes, along the lateral border of the pectoralis major m.; 2) lateral nodes, located along the distal axillary v.; 3) central nodes, centrally located along axillary v.; 4) subscapular nodes, located along the subscapular v. and its tributaries; 5) apical nodes, located at the apex of axilla
axillary nodes, apical apex of the axilla lateral axillary nodes; central axillary nodes; subscapular axillary nodes; pectoral nodes; accessory lymphatic vessels from the mammary gland; lymphatic vessels accompanying the cephalic v. subclavian lymphatic trunk; deep cervical lymph nodes upper limb, most of the mammary gland, some of the anterolateral chest wall, posterior thoracic wall and scapular region apical axillary nodes are 6- 12 in number; this is the highest node group in the axilla and all other node groups drain through these nodes; a very important group of nodes in cases of metastatic spread of breast cancer; connections to deep cervical nodes may result in spread of breast cancer through the deep neck
axillary nodes, central in the fat of the axilla lateral axillary nodes; pectoral nodes; subscapular nodes; lymphatic vessels from the mammary gland and upper limb apical axillary nodes upper limb, most of the mammary gland, some of the anterolateral chest wall, posterior thoracic wall and scapular region central axillary nodes are 4 or 5 in number; they can be involved in cancer of the mammary gland
axillary nodes, humeral (lateral) along the distal axillary v. cubital nodes; lymphatic vessels of the arm central axillary nodes, apical axillary nodes upper limb lateral axillary nodes become inflamed during upper limb infections; also known as: brachial nodes
axillary nodes, pectoral (anterior) along the lateral border of the pectoralis major m. along the course of the lateral thoracic vessels lymphatic vessels from the mammary gland and anterolateral thoracic wall central axillary nodes anterolateral thoracic wall and muscles; most of the mammary gland an important group of nodes to examine during a breast physical exam; also known as: anterior axillary nodes
axillary nodes, subscapular (posterior) along the course of the subscapular vessels lymphatic vessels from the skin of the back and back of the neck; lymphatic vessels from the muscles of the scapular region central axillary nodes skin of the back and back of the neck; muscles of the scapular and subscapular regions subscapular axillary nodes are 5 or 6 in number; also known as: posterior axillary nodes
parasternal nodes lateral border of sternum, along the course of the internal thoracic vessels anterior phrenic nodes, lymphatic vessels from the anterior thoracic wall larger lymphatic vessels in the root of the neck medial side of the mammary gland; medial part of the anterior chest wall and muscles parasternal nodes constitute an important drainage pattern in cases of cancer of the mammary gland because they communicate with hepatic nodes; one or two parasternal nodes may be found in the anterior end of intercostal spaces 1-6; also known as: sternal nodes
supraclavicular nodes in and around carotid sheath below level of omohyoid superior deep cervical nodes, transverse cervical nodes, spinal accessory nodes efferents form the jugular lymphatic trunk head and neck also known as: inferior deep cervical nodes


Other Tables of Interest:


Back Region


Upper Limb

All Anatomy Tables

Tables Organized by System Tables Organized by Region


Some of the material presented in these tables is contained in the book:
MedCharts Anatomy by Thomas R. Gest and Jaye Schlesinger
Published by ILOC, Inc., New York. Copyright 1995.

Content of tables edited for use in this course by Patrick W. Tank, Ph.D.
Copyright 2005, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences.

Unauthorized use is prohibited.