Muscles of the Pectoral Region and Back Flashcards
Pectoralis major origin
anterior sternal end of the clavicle, sternum, ribs 1-6, aponeurosis of the external oblique
Pectoralis major insertion
crest of the greater tubercle of the humerus
Pectoralis major nerve
lateral and medial pectoral nerve
Pectoralis major action
adducts, flexes, extends (when it is flexed, not backwards extension), and medially rotates arm
Pectoralis minor origin
rips 3-5 (costochondral junction)
Pectoralis minor insertion
coracoid process
Pectoralis minor nerve
medial pectoral
Pectoralis minor action
depresses scapula, elevate ribs (stabilizes scapula by drawing it inferiorly and anteriorly against the thoracic wall)
Subclavius origin
1st rib (costochondral junction)
Subclavius insertion
inferior acromial end of clavicle
Subclavius nerve
subclavian
Subclavius action
flexes clavicle or elevates 1st rib
Serratus anterior origin
ribs 1-8(9)
Serratus anterior insertion
deep medial border of the scapula
Serratus anterior nerve
long thoracic
Serratus anterior action
rotate and protract scapula (pulls medial border forward), elevate ribs, it is the deepest scapula muscle
Trapezius origin
occipital protuberance through T12 nuchal ligament
Trapezius insertion
superior margin of scapular spine and anterior acromial end of the clavicle
Trapezius nerve
accessory and cervical plexus
Trapezius action
rotate scapula, abduct and extend head
Levator scapulae origin
transverse processes C1-4
Levator scapulae insertion
superior angle of scapula
Levator scapulae nerve
dorsal scapular
Levator scapulae action
elevate scapula
