Rhomboid Major and Rhomboid Minor Origin, Insertion, Action

Rhomboid Major Muscle

Origin: The spinous processes of T2 to T5
Insertion: Vertebral border of the scapula, from inferior to the scapular spine to the inferior angle
Actions: Retraction of the scapula, downward rotation of the scapula
Innervation: Dorsal scapular nerve (C5)
Blood Supply: Dorsal scapular artery and dorsal branches of the posterior intercostal arteries

Primary Actions of the Rhomboid Major

1. Retraction of the scapula

Agonists:

Trapezius (middle part)
Rhomboid minor

Antagonists:

Serratus anterior
Pectoralis minor

Visit the rhomboids pain page for information about the pain and symptoms of muscle dysfunction.

Secondary Actions of the Rhomboid Major

2. Downward rotation of the scapula

Agonists:

Levator scapulae
Serratus anterior (upper fibers)
Rhomboid minor
Pectoralis minor
Trapezius (middle fibers)

Antagonists:

Trapezius (upper and lower part)
Serratus anterior (lower fibers)

Middle part of trapezius is a stabilizer.

Rhomboid Minor Muscle

Origin: Nuchal ligament and the spinous processes of C7 and T1
Insertion: The vertebral border of the scapula, adjacent to the scapular spine
Actions: Retraction of the scapula, downward rotation of the scapula
Innervation: Dorsal scapular nerve (C5)
Blood Supply: Dorsal scapular artery and dorsal branches of the posterior intercostal arteries