Flashcards in Arm + Axilla Deck (21):
how many muscles are in the posterior compartment?
one - triceps brachii
what are the loose major functions of the two compartments?
posterior = extensor
anterior = flexor
name the three heads of the triceps, and where their joint tendon inserts
long, lateral and medial (medial deepest, covered by the other two)
insert onto olecranon of ulna
what is the action and innervation of triceps brachii?
radial nerve (C6-8, mainly C7)
extension @ elbow
how many muscles are in the anterior compartment?
3 (BBC) - biceps / brachialis / coracobrachialis
which nerve innervates the anterior compartment muscles?
what is the main action of biceps brachii?
supination of forearm when flexed at elbow
also flexes @ arm and shoulder
what forms the roof of the cubital fossa?
what do the two heads of the biceps combine to attach to?
what is the action of the coracobrachialis?
flexor @ shoulder
what is the action of the brachialis?
main flexor @ elbow
which muscle forms the base of the cubital fossa?
what makes up the anterior border of the axilla?
pectoralis major and minor
what makes up the medial border of the axilla?
serratus anterior and thoracic wall
what makes up the posterior border of the axilla?
scapularis, teres major, lattissimus dorsi
what makes up the lateral border of the axilla?
bicipital groove on the humerus
what are the 3 pathways exiting the axilla?
main one is straight into the upper limb.
quadrangular space - gap in posterior wall of axilla, access to posterior arm and shoulder area
clavipectoral triangle - opening in anterior wall
what passes through the quadrangular space?
axillary nerve and posterior circumflex humeral artery
what passes through the clavipectoral triangle?
cephalic vein enters, medial and lateral pectoral nerves leave
what 3 structures border the clavipectoral triangle?
pectoralis major, deltoid and clavicle