The upper trapezius is the most superficial and visible portion of the trapezius, running from the cervical spine and skull to the lateral clavicle. It elevates the scapula for shrugging and contributes to the upward rotation force couple with the lower trapezius and serratus anterior that is essential for arm elevation. It is the most commonly overactive muscle in the shoulder girdle complex, being recruited as a prime mover substitute when the middle and lower trapezius are inhibited by pain or weakness.
| Origin | Medial third of the superior nuchal line, external occipital protuberance, and ligamentum nuchae from C1 through C7 |
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| Insertion | Posterior border of the lateral third of the clavicle |
| Nerve Supply | Spinal accessory nerve (CN XI) for motor; Cervical plexus (C3, C4) for proprioception |
| Blood Supply | Transverse cervical artery |
| Actions | Elevation of the scapula; Upward rotation of the scapula (when combined with lower trapezius); Ipsilateral lateral flexion and contralateral rotation of the head (when the scapula is fixed) |
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In the scapular upward rotation force couple, the upper trapezius acts through the clavicle to rotate the AC joint, complementing the lower trapezius pulling the scapular spine medially and the serratus anterior pushing the inferior angle laterally to produce the combined upward rotation needed for overhead arm elevation.
Upper trapezius trigger points are among the most commonly treated myofascial pain locations, producing the characteristic unilateral neck and temporal headache that refers from the muscle belly to the occiput and temple. Elevated and internally rotated scapular posture from upper trapezius overactivity and lower trapezius inhibition is the most common scapular dyskinesis pattern in shoulder pathology. CN XI palsy from posterior triangle surgery produces trapezius palsy including the upper portion, producing shoulder drop that is distinct from pure levator scapulae or rhomboid weakness.
The upper trapezius is easily palpated as the sloping muscle mass between the neck and shoulder, with trigger points reproducing the typical unilateral cervicogenic headache pattern when pressed.
Myofascial trigger points producing cervicogenic headache and neck-shoulder pain in the classic trapezius referral pattern, managed with dry needling, soft tissue release, and postural correction.
