Sternocostal Head of Pectoralis Major Muscle

The sternocostal head of the pectoralis major muscle is one of three origins for the pectoralis major. It arises from the sternum and creates adduction in its insertion with the humerus bone. Broadly, “pectoral” is a term relating to the chest, and the pectoralis major is a large, fan-shaped muscle that covers much of the front upper chest. It begins at the breastbone (sternum) and the cartilage of the second to the sixth ribs and is attached to the collarbone (clavicle) to converge on...