Back/Pectoral Region/Rotator Cuffs Flashcards
name the superficial back muscles
trapezius, lattissimus dorsi, levator scapulae + rhomboids (major and minor)
which muscles are involved in arm abduction?
supraspinatus (5-15 degrees), deltoid (up to 90), trapezius
what is the action and innervation of the trapezius?
accessory nerve.
upper fibres = abduction of arm
middle fibres = retract scapula
lower fibres = pull scapula inferiorly
what is the action and innervation of the lattissimus dorsi?
thoracodorsal nerve.
extends, adducts + medially rotates upper limb
what is the action and innervation of levator scapulae?
dorsal scapular nerve
elevates scapula
what muscle does the thoracodorsal nerve innervate?
lattissimus dorsi
what does the dorsal scapular nerve innervate?
levator scapulae and both rhomboids
which is superior, rhomboid major or minor?
minor
what is the action and innervation of rhomboid major/minor?
dorsal scapular nerve
retracts + rotates scapula
which wall of the axilla do the pec major/minor muscles contribute to?
anterior
what are the two heads of pectoralis major, and where do they insert to?
clavicular and sternocostal
both insert together in the bicipital groove
what is the action and innervation of pectoralis major?
adduct and medially rotate arm (clavicular head also flexes)
medial + lateral pectoral nerves
what is the action and innervation of pectoralis minor?
medial pectoral nerve
depresses shoulder
to which wall of the axilla does the serratus anterior contribute?
medial
what is the action and innervation of serratus anterior?
long thoracic nerve
rotates scapula, allowing arm to be raised over 90 degrees