- Rhomboid Major:
origin: spinous process of 2nd to 5th thoracic vertebrae;
insertion: medial border of scapula from spine to inferior angle;
action: adducts scapula and elevation of medial border; the inferior fibers aid in rotating the glenoid cavity inferior;
nerve supply: dorsal scapular (C4, C5);
synergists: upper, middle, and lower trapezius, levator scapula, latissimus dorsi, rhomboid minor;
- Rhomboid Minor:
origin: ligamentum nuchae, spinous process of C7 and T1;
insertion: medial border of scapula at the root of the spine of scapula;
action: adducts and aids elevation of scapula;
nerve supply: dorsal scapula, C4, C5;
synergists: upper, middle, and lower trapezius, levator scapula, latissimus dorsi and rhomboid major