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Upper BackSource-checked

Rhomboids (major & minor)

Rhomboideus major et minor

Pronunciation: ROM-boyds

For beginners

These muscles pull your shoulder blades together toward the spine, like standing up tall and 'proud'. They are important for posture and for rowing movements.

Show the advanced explanation

With the middle trapezius they retract the scapula; weakness or overstretch (from a rounded posture) can contribute to a protracted, forward-shoulder position.

Structure & function

Location
Muscles between the spine and the inner edge of each shoulder blade, under the trapezius.
Origin
Spinous processes of the lower cervical and upper thoracic vertebrae.
Insertion
Medial (inner) border of the scapula.
Main action(s)
Retract (squeeze together) the scapulae and help rotate them downward; steady the shoulder blade against the rib cage.
Joint(s) crossed
Scapulothoracic articulation
Movement plane
transverse
Innervation
Dorsal scapular nerve (C4–C5)
In daily movement
Pulling the shoulder blades back — good upright posture.
In exercise
Prime movers of scapular retraction in rows and reverse flyes.
Commonly confused with
Hidden beneath the trapezius, so their action is often credited to the traps.
Common misconceptions
You cannot 'see' the rhomboids, but they are key posture and pulling muscles.

Exercises that use this muscle

As a primary mover

As a secondary / stabilizer

⚠ Safety note

Aching between the shoulder blades from posture is common; persistent or radiating pain needs assessment.

Sources

The rhomboids retract and stabilize the scapula.

Anatomy and Physiology 2eOpenStax, Rice University · Ch. 11.5 Muscles of the Pectoral Girdle and Upper Limbs

Peer-reviewed textbook · License: CC BY-NC-SA 4.0 · Last checked 2026-07-19

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