shoulder girdle muscles

upper trapezius origin

external occipital protuberance, spinous process of cervical vertebrae

upper trapezius insertion

lateral end of clavicle, acromion process

upper trapezius actions

scapular elevation

upward rotation

retraction

upper trapezius nerve

spinal accessory (cranial nerve 11), C3 and C4

middle trapezius origin

spinous process of C7-T3

middle trapezius insertion

medial aspect of acromion and spine of scapula

middle trapezius actions

scapular retraction

upward rotation

middle trapezius nerve

spinal accessory (cranial nerve 11), C3 and C4

lower trapezius origin

spinous process of T4-T12 via supraspinal ligament

lower trapezius insertion

base of spine of scapula

lower trapezius actions

scapular depression,

upward rotation,

retraction

levator scapula origin

transverse processes 1-C4

levator scapula insertion

vertebral border of scapula between superior angle and spine of scapula

levator scapula actions

elavation

scapular depression

downward rotation

levator scapula nerves

C3-C4 and dorsal scapula nerve(C5)

rhomboid origin

spinous processes of C7-T5

rhomboid insertion

vertebral border of scapula between base of spine of scapula and inferior angle

rhomboid actions

scapular retraction

elevation

downward rotation

rhomboid nerves

dorsal scapular nerve (C5)

serratus anterior origin

lateral surface of first through eighth ribs

serratus anterior insertion

vertebral border of the scapula, anterior surface

serratus anterior actions

scapular protraction

upward rotation

pectoralis minor origin

anterior surface, 3rd through 5th ribs

pectoralis minor insertion

coracoid process of scapula

pectoralis minor actions

scapular depression

protraction

downward rotation

tilt

pectoralis minor nerve

medial pectoral nerve (C8,T1)