Anatomy and Physiology Review – Breast and Axilla

Breasts are mammary (milk-producing) glands that change in size, shape, and function throughout the lifespan. Breast tissue is composed of skin and subcutaneous tissue. The breasts lie over the pectoral muscles of the chest and are attached to the chest wall by Cooper’s ligaments. Much like the abdominal quadrants, breasts are divided into quadrants (upper outer and inner quadrants and lower inner and outer quadrants. The tail of Spence is the auxiliary extension of the upper and outer quadrants of each breast (Bickley, 2021; Thompson, 2018).

Lymphatic drainage of the breast occurs through axillary lymph nodes. These nodes are organized into six groups that lie along the chest wall. The central nodes are most often palpable during a physical assessment (Bickley, 2021; Thompson, 2018).