Inframammary cleft

The inframammary cleft (also known as the inframammary fold or inframammary crease) is the anatomical landmark defined by the junction where the inferior pole of the breast meets the chest wall. It represents a distinct curvilinear skin fold that demarcates the lower boundary of the breast mound from the anterior thoracic wall.

Anatomical Characteristics

The inframammary fold is formed by a condensation of superficial fascia (the superficial fascial system) that firmly adheres to the underlying deep fascia of the chest wall, typically at the level of the 5th to 6th rib. This fibrous attachment — sometimes referred to as the "inframammary ligament" — creates a fixed point of adherence between the dermis and the underlying musculoskeletal structures. Key features include:

• Structural support: The fold acts as a natural suspensory structure, helping to define the inferior extent of the breast and maintain its shape and position on the chest wall.

• Fibrous composition: It is composed of a dense band of connective tissue fibers (including contributions from the superficial fascial system and Cooper's ligaments) that anchor the skin to the periosteum of the ribs and the pectoralis fascia.

• Positional variability: Its precise location varies among individuals based on breast size, body habitus, age, and hormonal influences, typically lying between the 5th and 7th ribs.