Summary Origin Minor: nuchal ligament and spinous processes of C7 and T1 vertebrae; Major: spinous processes of T2 - T5 vertebrae Insertion Medial border of scapula from level of spine to inferior angle Action Retract scapula and rotate it to depress glenoid cavity; fix scapula to thoracic wall Innervation Dorsal scapular nerve ( C4 and C5) (C4, C5) Arterial Supply Dorsal scapular artery