Pectoral Region and Axilla Flashcards
origin of pectoralis major?
clavicular head: medial 1/2 of clavicle sternoclavicular head: sternum, costal cartilatges, aponeurosis of external abdominal obluique
insertion of pectoralis major?
lateral lip of intertubercular sulcus
action of pectoralis major?
flexes, adducts and medially rotates arm
innervation of pectoralis major?
medial and lateral pectoral nerve
specific function of clavicular head of pectoralis major?
flexes an all the way extended arm
specific function of sternocostal head of pectoralis major?
extends a flexed arm
origin of pectoralis minor?
ribs 3-5 near costal cartilages
insertion of pectoralis minor?
coracoid process of scapula
action of pectoralis minor?
stabilizes scapula by pulling it inferior and anterior
innervation of pectoralis minor?
medial pectoral nerve (C8, T1)
origin of subclavius?
rib 1 near costal cartilage
insertion of subclavius
middle 1/3 of clavicle
action of subclavius?
anchors and depresses clavicle
innervation of subclavius?
nerve to subclavius (C5,C6)
where is the clavipectoral fascia?
deep to pectoralis major, invests to pectoralis minor and subclavius
origin of serratus anterior?
ribs 1-8 or 9
insertion of serratus anterior?
medial border of scapula (anterior surface)
action of serratus anterior?
protracts scapula, upward rotation of glenoid, helps keep medial border and inferior angle opposed to thoracic wall (holds scapula to thoracic wall)
innervation of serratus anterior?
long thoracic nerve (is on the superficial surface of the muscle)
what could happen if the long thoracic nerve is damaged?
the serratus anterior could be paralyzed, causing winging of the scapula (protrusion of scapula away from the thoracic wall) (ask patient to push on a wall with outstretched arm)
what makes up the anterior wall of the axilla?
pectoralis major, pectoralis minor, subclavius, clavipectoral fascia
what makes up the lateral wall of the axilla?
intertubercular sulcus
what makes up the posterior wall of the axilla?
subscapularis, teres major, teres minor, latissimus dorsi, long head of triceps
what makes up the floor of the axilla
skin of the armpit





