OIA Pectoral Girdle
Serratus anterior action
rotates scapula so that its inferior angle moves laterally and upward
Trapezius insertion
A continuous insertion along acromion and spine of scapula and lateral third of clavicle
Subclavius insertion
Groove on inferior surface of clavicle
Trapezius origin
Occipital bone; ligamentum nuchae; spines of C7 and all thoracic vertebrae
Pectoralis minor origin
anterior surface of ribs 3-5
Serratus anterior origin
by a series of muscle slips from ribs 1-8 (or 9)
Pectoralis minor insertion
coracoid process of scapula
Subclavius origin
costal cartilage of rib 1
Levator scapulae action
elevates and adducts scapula
Serratus anterior insertion
entire anterior surface of vertebral border of scapula
Subclavius action
helps stabilize and depress pectoral girdle
Rhomboids insertion
medial border of scapula
Levator scapulae insertion
medial border of scapula superior to spine
Rhomboids origin
spinous processes of C7 and T1 (minor) and spinous processes of T2-T5 (major)
Rhomboids action
stabilizes scapula
Trapezius action
stabilizes, raises, retracts, and rotates scapula
Levator scapulae origin
transverse processes of C1-C4
Pectoralis minor action
with ribs fixed, draws scapula forward and downward