The rhomboid major originates from the spines of vertebrae TII to TV and from the intervening supraspinous ligaments. It descends laterally to insert along the posterior surface of the medial border of the scapula from the insertion of the rhomboid minor to the inferior angle.
The rhomboid muscles are innervated by the dorsal scapular nerve, which is a branch of the brachial plexus.
The rhomboid minor and major retract and elevate the scapula.