Trapezius origin and insertion

Trapezius runs from the occipital bone, seventh cervical vertebra and first to twelfth thoracic vertebrae to the clavicle and scapula. It has three parts: the descending part, the transverse part and the ascending part.

What are the origin and insertion of trapezius?

Trapezius arises from the external occipital protuberance and the superior nuchal line; the ligamentum nuchae, to the cervical spines; the spine of the seventh cervical vertebra; the spines of the first to third thoracic vertebrae; and the spines of the lower thoracic vertebrae, to the twelfth. It inserts on the back of the lateral third of the clavicle, the acromion and the upper lip of the spine of the scapula, and the tubercle at the medial end of the spine of the scapula. Its main actions are elevation of the scapula (descending part), retraction of the scapula (transverse part), and upward rotation of the scapula (descending and ascending parts together). It is supplied by the accessory nerve, cranial nerve XI, with C3 and C4 for sensation. The attachments, actions and nerve follow Gray (1918).

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Every attachment and its bone

Origins 7

Origins of trapezius, with the bone each is on
Attachment	Bone	Part
External occipital protuberance and the superior nuchal line	Occipital bone	Descending part
Ligamentum nuchae, to the cervical spines	None The ligamentum nuchae is not segmented in BodyParts3D, so this attachment cannot be painted.	Descending part
Spine of the seventh cervical vertebra	Seventh cervical vertebra	Transverse part
Spine of the first thoracic vertebra	First thoracic vertebra	Transverse part
Spine of the second thoracic vertebra	Second thoracic vertebra	Transverse part
Spine of the third thoracic vertebra	Third thoracic vertebra	Transverse part
Spines of the lower thoracic vertebrae, to the twelfth	Fourth to twelfth thoracic vertebrae	Ascending part

Insertions 3

Insertions of trapezius, with the bone each is on
Attachment	Bone	Part
Back of the lateral third of the clavicle	Clavicle	Descending part
Acromion and the upper lip of the spine of the scapula	Scapula	Transverse part
Tubercle at the medial end of the spine of the scapula	Scapula	Ascending part

Actions

The actions of trapezius, and which are its main ones
Action	What moves	Main or assisting
Elevation, descending part	The shoulder blade rises	Main action
Retraction, transverse part	The shoulder blade moves towards the spine	Main action
Depression, ascending part	The shoulder blade drops	Assists
Upward rotation, descending and ascending parts together	The shoulder blade turns so the socket faces up	Main action

Each action is stated in the anatomical position: standing, arms by the sides, palms forward.

Innervation

The accessory nerve, cranial nerve XI, with C3 and C4 for sensation.

Lifts that use trapezius

A prime mover produces the lift’s main joint action against the load; a synergist assists that action, or adds a secondary action the lift needs. Each role is the one the lift’s own page gives, for the technique that page states.

Prime mover in 1

Lifts in which trapezius is a prime mover, with what it does there
Lift	Part	What it does there
Bent-over barbell row	Middle trapezius	Pulling the shoulder blades together

Synergist in 9

Lifts in which trapezius is a synergist, with what it does there
Lift	Part	What it does there
Parallel-bar dip	Lower trapezius	Pulling the shoulder blades down
Standing overhead press	Upper trapezius	Rotating the shoulder blades upward
Standing overhead press	Lower trapezius	Rotating the shoulder blades upward
Bent-over barbell row	Lower trapezius	Steadying the shoulder blades as they retract
Pull-up	Lower trapezius	Pulling the shoulder blades down More active in the pull-up than the chin-up (Youdas et al. 2010).
Chin-up	Lower trapezius	Pulling the shoulder blades down
Lat pulldown	Middle trapezius	Drawing the shoulder blades in
Lat pulldown	Lower trapezius	Pulling the shoulder blades down
Dumbbell lateral raise	Upper trapezius	Rotating the shoulder blade upward

Its parts are also stabilizers in the back squat (upper trapezius and middle trapezius), front squat (upper trapezius), conventional deadlift (upper trapezius, middle trapezius and lower trapezius), sumo deadlift (upper trapezius), Romanian deadlift (upper trapezius), Bulgarian split squat (upper trapezius), flat bench press (middle trapezius), incline bench press (middle trapezius), dumbbell lateral raise (middle trapezius) and barbell biceps curl (upper trapezius).

Sources

Gray (1918), Myology, the muscles connecting the upper extremity to the vertebral column

Each lift role is from that lift’s page in muscles worked by exercise, which names the sources it follows.

See it in 3D

Visualiser · Biology Muscle Origin, Insertion and Action Explorer Paint a muscle’s origin and insertion on real 3D bones, or click a bone to see what attaches to it. Visualiser · Biology Back Muscles Explorer 58 back muscle meshes, in six dissection layers. Visualiser · Biology Muscles Worked by Exercise 3D Explorer Choose a lift and a real body lights its prime movers, synergists and stabilisers, front and back, with the same muscles in 3D.