The trapezius muscle is a large, triangular, paired muscle located on the posterior aspect of the neck and thorax. When viewed together, this pair forms a diamond or trapezoid shape, hence its name. The trapezius has many attachment points, extending from the skull and vertebral column to the shoulder girdle. The trapezius belongs to the superficial layer of the extrinsic muscles of the back, along with latissimus dorsi, rhomboid major and minor, and levator scapulae muscles. The trapezius is la