axilla and arm LOs Flashcards
aconeus m.
- BL: lateral epicondyle of humerus > lateral surface of olecranon process (ulna)
- action: extension of elbow
- innervation: radial nerve
- SC segment: C7-8

biceps brachii m.
- BL: coracoid process (short head), supraglenoid tubercle (long head) of scapula > radial tuberosity and deep antebrachial fascia (through bicipital aponeurosis)
- action: flexion of shoulder and elbow, supination of forearm
- innervation: musculocutaneous nerve
- SC segment: C5-6

brachialis m.
- BL: distal anterior shaft of humerus, lateral and medial intermuscular septa > coronoid process and ulnar tuberosity
- action: flexion of elbow
- innervation: musculocutaneous nerve, small branch of radial nerve
- SC segment: C5-6

coracobrachialis m.
- BL: coracoid process > proximal medial shaft of humerus
- action: flexion and adduction of shoulder
- innervation: musculocutaneous nerve
- SC segment: C6-7

triceps brachii m.
- BL: infraglenoid tubercle of scapula (long head), proximal posterolateral (lateral head) and distal posteromedial (medial) shaft of humerus > olecranon process (ulna)
- action: extension of shoulder (long head), extension of elbow (long, medial, lateral)
- innervation: radial nerve
- SC segment: C6-T1

boundaries of axilla
- apex: first rib/clavicle
- base: skin of armpit
- anterior: pectoral mm.
- posterior: scapula, subscapular m.
- medial: thoracic wall, serratus anterior m.
- lateral: humerus
C4-5 nerve(s)
dorsal scapular
C4-6 nerve(s)
suprascapular
C5-6 nerve(s)
axillary
subclavian
upper subscapular
lower subscapular
C5-7 nerve(s)
musculocutaenous
long thoracic
lateral pectoral
C5-T1 nerve(s)
median
radial
C6-8 nerve(s)
thoracodorsal
C7-T1 nerve(s)
C8-T1 nerve(s)
medial pectoral
medial cutaneous of arm
medial cutaneous of forearm
dorsal scapular n. functions
C4-5
postganglionic sympathetic
motor
- to levator scapulaee and rhomboid mm.
long thoracic n. functions
C5-7
sesnsory
postganglionic sympathetic
motor
- to serratus anterior
suprascapular n. functions
C4-6
sensory
postganglionic sympathetic
motor
- to supraspinatus and infraspinatus mm.
subclavian n. functions
C5-6
sensory
postganglionic sympathetic
motor
- to subclavius m.
lateral pectoral nerve functions
C5-7
sensory
postganglionic sympathetic
motor
- to pectoralis major and minor mm.
musculocutaneous n. functions
C5-7
sensory
postganglionic sympathetic
motor
- S/PS/M to biceps brachii, brachialis, coracobrachialis mm.
- S/PS to lateral aspect of forearm
median n. functions
C5-T1
sensory
postganglionic sympathetic
motor
- S/PS/M to flexor carpi radialis, palmaris longus, flexor digitorum superficialis, pronator teres, flexor pollicis longus, flexor digitorum profundus, pronator quadratus, 2 lateral lumbrical, flexor pollicis brevis, abductor pollicis brevis, opponens pollicis mm.
- S/PS skin overlaying radial aspect of palm and digits 1-4
medial pectoral n. functions
C8-T1
sensory
postganglionic sympathetic
motor
- to pectoralis major and minor mm.
medial cutaenous n. of arm and forearm functions
C8-T1
sensory
postganglinoic sympathetic
- to skin overlying medial aspect of arm and forearm
ulnar n. functions
C7-T1
sensory
postganglionic sympathetic
motor
- S/PS/M to flexor carpi ulnaris, flexor digitorum profundus, abductor digiti minimi, flexor pollicis brevis, opponens digiti, palmar interossei, dorsal interossei, medial 2 lumbricals, adductor pollicis mm.
- S/PS to skin overlying ulnar side of palm
upper subscapular n. functions
C5-6
sensory
postganglionic sympathetic
motor
- to subscapularis m.
thoracodorsal n. functions
C6-8
sensory
postganglionic sympathetic
motor
- to latissimus dorsi m.
lower subscapular n. functions
C5-6
sensory
postganglionic sympathetic
motor
- to teres major and subscapularis mm.
axillary n. functions
C5-6
sensory
postganglinoic sympathetic
motor
- S/PS/M to deltoid and teres minor mm.
- S/PS to skin overlying superior lateral aspect of arm
radial n. functions
C5-T1
sensory
postganglionic sympathetic
motor
- S/PS/M to tripces brachii, brachialis, anconeus, brachioradialis, supinator, extensor carpi radialis longus, extensor carpi radialis bravis, extensor carpi ulnaris, extensor digitorum, extensor digiti minimi, extensor indicis, extensor pollicis brevis, extensor pollicis longus, abductor pollicis longus mm.
- S/PS to skin overlying posterior aspect of forearm, radial side of dorsum of hand
brachial plexus

triangular space
inferior to teres minor
superior to teres major
medial to long head of triceps brachii
- contains circumflex scapular artery

triceps hiatus
lateral to triceps brachii long head
inferior to teres major
medial to humerus
- radial nerve
- profunda brachii artery

anterior arm
- contents: coracobrachilalis, biceps brachii, brachialis
- action: shoulder and elbow flection
- innervation: musculocutaneous n.
- blood supply: brachial a.
posterior compartment of arm
- contents: triceps brachii, anconeus
- action: shoulder and elbow extension
- innervation: radial n.
- blood supply: profunda brachii a.
most common direction of shoulder dislocation
inferior joint capsule not reinforced by rotator cuff or ligaments (especially abducted when arm is abducted)
anterior dislocation is 95% of shoulder dislocations
path of drainage of axillary lymph nodes to venous system
humeral (hand, forearm, medial arm, deep forearm)
pectoral (anterior thorax, breast)
subscapular (posterior shoulder, posterior thorax, scapula)
central
apical
right subclavian trunk
right lymphatic duct
venous angle
right brachiocephalic vein
superior vena cava
right atrium


cephalic vein (cross section)


long head of biceps brachii (cross section)


short head of biceps brachii (cross section)


lateral head of triceps brachii (cross section)


medial head of triceps brachii (cross section)


long head of triceps brachii (cross section)
