Scapular and pectoral region Flashcards
name the muscles of the pectoral girdle (rotator cuff)
deltiod, teres major and minor, supraspinitus, infraspinitus, subscapularis (SITS mnemonic for rotator cuff)
origin of deltiod
lateral clavicle, acromion & spine of scapula
insertion of deltiod
deltiod tuberosity of humerus
action of deltiod
aducts, flexus, extends, rotates humerus
supply of deltiod
axillary nerve (C5, C6) and POSTERIOR circumflex humeral vessels
origin of teres major
inferior angle of scapula
insertion of teres major
crest of lesser tubercle of humerus
action of teres major
adducts, extends & medially rotates humerus (traps “little helper)
supply of teres major
lower subscapular (C5-C6) nerve & subscapular vessels
origin of supraspinatus
supraspinous fossa
insertion of supraspinatus
greater tubercle of humerus
action of supraspinatus
abducts humerus (only 1st 15 degrees)
supply of supraspinatus
suprascapular nerves (C5-6) & vessels, dorsal scapular vessels
origin of infraspinatus
infraspinous fossa
insertion of infraspinatus
greater tubercle of humerus
action of infraspinatus
lateral rotation of humerus
supply of infraspinatus
suprascapular nerve (C5-6) & vessels, subscapular vessels
origin of teres minor
lateral border of scapula
insertion of teres minor
greater tubercle of humerus
action of teres minor
lateral rotation of humerus (w/ infraspinatus)
supply of teres minor
axillary nerve & suprascapular (both C5-6) & subscapular vessels
origin of subscapularis
subscapular fossa
insertion of subscapularis
lesser tubercle of humerus
action of subscapularis
medial rotation of humerus
supply of subscapularis
upper & lower subscapular nerves (C5-6), subscapular vessels
what are the spaces of the shoulder region?
quadrangular space, triangular space, triangular interval
what does the quadrangular space transmit?
axillary nerve, posterior circumflex humeral artery
what lies beneath the triangular space?
circumflex scapular artery (deep to space)
what does the triangular interval transmit?
profunda brachii (deep brachial artery), radial nerve
boundaries of the quadrangular space
teres minor- superior, teres major- inferior, long head of triceps- medial, “Surgical neck” of humerus- lateral
boundaries of triangular space
teres minor- superior, teres major- inferior, long head of triceps- LATERAL
boundaries of triangular interval
teres major- superior, long head of triceps- medial, lateral head of triceps- lateral
which 2 main arteries give collateral circulation to scapular region?
thyrocervical trunk and subscapular artery
origin of pectoralis major
clavicle, sternum & ribs 2-6
insertion of pectoralis major
crest of greater tubercle of humerus
action of pectoralis major
adducts & medially rotates humerus
supply of pectoralis major
medial AND lateral pectoral nerve (C5-6, C8-T1), thoracoacromial vessels
origin of pectoralis minor
ribs 3-5
insertion of pectoralis minor
coracoid process of scapula
action of pectoralis minor
protracts scapula
supply of pectoralis minor
Medial pectoral nerve (C8 & T1), thoracoacromial vessels
arterial supply of pectoral region
lateral and internal thoracic arteries (mammary), thoracoacromial artery
what does the lateral thoracic artery supply?
supplies lateral thorax (shocking, I know), serratus anterior, lateral pec region, lateral breast
what does the internal thoracic artery supply?
anterior thorax, medial pectoral region, medial breast
what are the branches of the thoracoacromial artery?
Pectoral, clavicular, acromial, deltiod (Cadavers Are Dead People mneumonic)
what are the general sensory nerves to Pec region?
T1-T6, lateral and anterior cutaneous branches of intercostal nerves
the medial pectoral nerve
medial chord of brachial plexus, from ventral rami (C8-t1), pierces pec minor to get to pec major, supplies pec minor & part of pec major
Lateral pectoral nerve
lateral cord of brachial plexus, from ventral rami (c5-7), runs above pec minor, enters pec major
long thoracic nerve
from ventral rami (c5-7) like lat pec nerve, supplies serratus ant, damage gives winged scapula
