Muscles medially rotating the pectoral(shoulder) girdle

Rhomboid major

Rhomboid minor

Pectoralis minor

Levator scapulae

Movement of the inferior angle of the scapula towards the vertebral column is frequently produced by the action of gravity, being controlled by the eccentric activity of the lateral rotators. However, the above muscles contract strongly if the pectoral girdle is to be medially rotated against resistance, as when moving the weight of the body from a position of hanging from a bem to full chin-up. The notional axis of rotation is just below the spine of the scapula, towards the base. Pectoralis minor exerts a downward pull on the lateral side of this axis via its attachment to the coracoid process, while the rhomboids and levator scapulae pull upwards on the medial side. The resultant movement is shown in the picture below.