Detailed Representation of the Pectoralis Muscle

Description

Anterior thoracic anatomy is rendered with the mammary gland highlighted superficial to the pectoral fascia, while the pectoralis major is differentiated beneath it. The clavicular head arises from the medial clavicle and the sternocostal head from the sternum and costal cartilages, converging laterally into a broad tendon that inserts on the lateral lip of the intertubercular sulcus of the humerus. Deep and slightly medial, the pectoralis minor runs from ribs 3 to 5 to the coracoid process, forming part of the anterior wall of the axilla; the deltoid lies lateral, framing the deltopectoral interval. Breast-on-pectoral relationships drive surgical planes. By separating glandular tissue (mammary parenchyma) from the underlying pectoral fascia at the retromammary space, surgeons can perform skin-sparing mastectomy and reconstructive approaches while preserving or intentionally releasing the pectoralis major for subpectoral implant placement. The illustration also supports teaching of why invasive carcinoma can tether the skin through Cooper ligaments and why lymphatic drainage tracks toward axillary nodes along the lateral border of pectoralis minor, a standard landmark for level I to III nodal staging. Use this asset in gross anatomy labs, breast surgery and oncology lecture decks, or patient-facing education that explains subglandular versus subpectoral reconstruction and the muscular boundaries of the axilla. It also fits well in medical publishing layouts that need clean differentiation of pectoralis muscle, fascia, tendon, and female breast tissue in one frame. Anatomical accuracy verified by SciePro's Medical Advisory Board.