Where does the trapezius insert?

Where does the trapezius insert?

• A. Intertubercular groove of the humerus.
• B. Lateral third of the clavicle, acromion, and spine of the scapula.
• C. External occipital protuberance and spinous processes of C7-T12.
• D. Thoracolumbar fascia.

Answer: (B)

Where the trapezius inserts determines how it moves the shoulder girdle. It attaches to the lateral third of the clavicle, the acromion, and the spine of the scapula. This arrangement lets the muscle’s different fiber regions produce distinct scapular movements: the upper fibers elevate the clavicle and scapula, the middle fibers retract the scapula, and the lower fibers depress the scapula and assist with upward rotation. Other options point to insertions on the humerus or to origins of the trapezius, not its insertion. Therefore, the insertion on the lateral clavicle, acromion, and spine of the scapula is the correct answer.

Where the trapezius inserts determines how it moves the shoulder girdle. It attaches to the lateral third of the clavicle, the acromion, and the spine of the scapula. This arrangement lets the muscle’s different fiber regions produce distinct scapular movements: the upper fibers elevate the clavicle and scapula, the middle fibers retract the scapula, and the lower fibers depress the scapula and assist with upward rotation. Other options point to insertions on the humerus or to origins of the trapezius, not its insertion. Therefore, the insertion on the lateral clavicle, acromion, and spine of the scapula is the correct answer.