The pectoralis minor is one of the most superficial anterior thoracic muscles, located below the pectoralis major muscle.
Origin: costal cartilages and anterior surfaces of ribs 3 - 5.
Insertion: medial border and coracoid process of the scapula.
Action: draws the scapula anteroinferiorly; stabilizes the scapula on the thoracic wall.
Innervation: medial and lateral pectoral nerve (C5 - T1).
Blood supply: pectoral and deltoid branches of the thoracoacromial artery, superior thoracic artery, lateral thoracic artery.