Pectoralis Major - Podcast Version 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x The pectoralis major is a muscle of the anterior chest wall. It is a large fan-shaped muscle, which is composed of a sternal head and a clavicular head. Attachments: Clavicular head originates from the anterior surface of the medial clavicle. Sternocostal head originates from the anterior surface of the sternum, the superior six costal cartilages and the aponeurosis of the external oblique muscle. The distal attachment of both heads is onto the intertubercular sulcus of the humerus. Function: Adduction and medial rotation of the upper limb. Innervation: Lateral and medial pectoral nerves. Blood supply: Pectoral branch of thoracoacromial artery and branches from the internal thoracic artery. By TeachMeSeries Ltd (2026) Fig 1The sternal and clavicular heads of the pectoralis major. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Pro Feature - Dissection Atlas You've Discovered a Pro Feature Access our Dissection Image Library Enhance your understanding with high-resolution dissection images showcasing real-life anatomy. Learn More Frequent questions What is the pectoralis major muscle? The pectoralis major is a large, fan-shaped muscle located on the anterior chest wall. It consists of two heads: the clavicular head and the sternocostal head. Where does the pectoralis major attach? The pectoralis major attaches proximally from the anterior surface of the medial clavicle and the sternum, as well as from the superior six costal cartilages and the external oblique muscle's aponeurosis. Its distal attachment is at the intertubercular sulcus of the humerus. What is the primary function of the pectoralis major? The primary functions of the pectoralis major are the adduction and medial rotation of the upper limb. This muscle plays a crucial role in movements such as pushing and lifting. Which nerves innervate the pectoralis major? The pectoralis major is innervated by the lateral and medial pectoral nerves. These nerves are responsible for transmitting signals that enable muscle contraction. What is the blood supply to the pectoralis major? The blood supply to the pectoralis major comes from the pectoral branch of the thoracoacromial artery and branches from the internal thoracic artery. This vascular supply is essential for the muscle's function and health. Rate This Article