Muscle Anatomy


The trapezius, a large and kite-shaped muscle, spans the upper back and neck, contributing to shoulder and neck movements.

Arising from the external occipital protuberance, the nuchal ligament, the spinous processes of the seventh cervical vertebra (C7), and the spinous processes of all thoracic vertebrae (T1-T12), the trapezius has its origin along the spine.

The muscle inserts into the lateral third of the clavicle, the acromion process, and the spine of the scapula, forming a broad attachment on the shoulder girdle.

The trapezius has multiple functions depending on its region:

  • The upper fibers elevate the scapula, assisting in movements like shrugging the shoulders.
  • The middle fibers retract the scapula, pulling it toward the spine.
  • The lower fibers depress the scapula, aiding in movements like lowering the shoulders.
    Overall, the trapezius plays a crucial role in stabilizing and coordinating movements of the shoulder girdle and neck.