Week V Muscles Flashcards
Upper Fibers of Trapezius
O: external occipital protuberance, superomedial (one third of the) nuchal line of the occiput and ligamentum nuchae
I: posterolateral (one third of the) clavicle
A: elevates the scapula at the scapulothoracic joint
upwardly rotates the scapula at the scapulothoracic joint
Middle Fibers of Trapezius
O: spinous processes (SPs) of C7-T3
I: acromion process and superior border of the scapular spine
A: adducts (retracts) the scapula at the scapulothoracic joint
Lower Fibers of Trapezius
O: spinous processes (SPs) of T4-T12
I: tubercle at the root of the spine of the scapula
A: depress the scapula at the scapulothoracic joint
upwardly rotates the scapula at the scapulothoracic joint
adducts (retracts) the scapula at the scapulothoracic joint
Rhomboids
O: spinous processes (SPs) of C7-T5
I: medial border of the scapula from the root of the spine to the inferior angle
A: adducts (retracts) the scapula at the scapulothoracic joint
elevates the scapula at the scapulothoracic joint
downwardly rotates the scapula at the scapulothoracic joint
Levator Scapula
O: transverse processes (TPs) of C1-C4
I: medial border of the scapula from the superior angle to the root of the spine of the scapula
A: elevates the scapula at the scapulothoracic joint
downwardly rotates the scapula at the scapulothoracic joint
Serratus Anterior
O: external surfaces of anterolateral ribs 1-9
I: anterior surface of the medial border of the scapula
A: abducts (protracts) the scapula at the scapulothoracic joint
upwardly rotates the scapula at the scapulothoracic joint
depress the scapula at the scapulothoracic joint
Pectoralis Minor
O: ribs 3-5
I: medial aspect of the coracoid process of the scapula
A: abducts (protracts) the scapula at the scapulothoracic joint
depresses the scapula at the scapulothoracic joint
downwardly rotates the scapula at the scapulothoracic joint
