Deltoid Muscle - Anterior and Middle Heads
The trapezius muscle is a large, diamond-shaped muscle that covers the neck and shoulder area.
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.
Learn the anatomy of the trapezius muscle faster with this trunk wall muscle reference chart.
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).
An Overview of the Trapezius Muscle
Muscles That Act On The Posterior Shoulder