Head & NeckSource-checked

Upper trapezius

Trapezius pars descendens (upper portion)

Pronunciation: truh-PEE-zee-us

Simplified front and lateral view of the neck showing the sternocleidomastoid on the sides, the scalenes deeper within, and the upper trapezius connecting the neck to the shoulders. The cervical vertebrae are shown as a central axis. — Head & neck — sternocleidomastoid, scalenes, splenius, and upper trapezius (simplified). A beginner-level schematic of the neck's primary muscles: sternocleidomastoid, scalenes, splenius capitis, and upper trapezius.
Illustration: Anatomy Learning Platform (original) · CC0-1.0 (public domain dedication)

For beginners

This is the muscle you feel when you shrug your shoulders. It also extends your neck backward and helps hold your head and shoulder together. In desk workers, it's often tight and tense.

Show the advanced explanation

The upper trapezius is a large, powerful muscle that is frequently overactive and shortened in forward-head posture. Chronic tightness here is a major driver of tension headaches and cervical pain. It works in tandem with the splenius capitis for neck extension, but if the splenius is weak, the upper trap becomes overloaded.

Structure & function

Location: The upper portion of the trapezius muscle, running from the base of the skull and upper neck down to the shoulder. It's the large, flat muscle you feel on the upper back and shoulder.
Origin: External occipital protuberance and ligamentum nuchae (the ligament at the back of the neck).
Insertion: Lateral third of the clavicle and acromion process of the scapula.
Main action(s): Elevates the scapula (shrugs the shoulder); assists in neck extension; stabilizes the scapula during upper-limb work.
Joint(s) crossed: Cervical spine (for extension); scapulothoracic articulation (for shoulder support)
Movement plane: frontal (elevation), sagittal (extension of the head/neck)
Innervation: Spinal accessory nerve (CN XI)
In daily movement: Shrugging the shoulders, bracing the neck against load, and stabilizing the shoulder during reaching and lifting.
In exercise: Secondary neck extensor; primary scapular elevator. Highly active in any overhead or carrying task.
Commonly confused with: Part of the larger trapezius muscle, which also has middle and lower portions with different actions (the lower trap helps depress and retract the scapula).
Common misconceptions: The upper trapezius is not a primary scapular retractor — that job is the middle and lower trapezius. Upper trap's main scapular action is ELEVATION (shrug).

⚠ Safety note

Excessive shrugging or neck-load (holding tension in the shoulders) is the primary driver of upper-trapezius strain. Conscious shoulder relaxation and postural awareness are key to prevention.

Sources

“The upper trapezius originates on the skull and ligamentum nuchae, inserts on the clavicle and scapula, and elevates the scapula and extends the head.”

Anatomy and Physiology 2e — OpenStax, Rice University · Ch. 11.6 Muscles of the Head, Neck, and Spine

Peer-reviewed textbook · License: CC BY-NC-SA 4.0 · Last checked 2026-07-19