Vastus Medialis Muscle
Attachments of Trapezius Muscle: Origin & Insertion
Origin: (proximal attachments)
a. Medial superior nuchal line and external protuberance of occipital bone, ligamentum nuchae and spinous process of C7-T12.
Insertion: (distal attachments)
a. Lateral clavicle, acromion and spine of scapula.
Actions on the shoulder (scapula):
a. Upper fibers elevate scapula.
b. Upper fibers upwardly rotate scapula.
c. Extend neck.
d. Middle fibers adduct (retract) scapula.
e. Lower fibers scapula.
f. Lower fibers help upper fibers upwardly scapula.
Innervation of Trapezius Muscle:
- C3, C4 and accessory cranial nerve (XI).