Summary Pectoralis Minor Origin 3rd to 5th ribs near their costal cartilages Insertion Medial border and superior surface of coracoid process of scapula Action Stabilizes scapula by drawing it inferiorly and anteriorly against thoracic wall Innervation Medial pectoral nerves (C8 and T1) Arterial Supply Pectoral branch of the thoracoacromial trunk