Mechanics of the normal woman's breast.

Knowledge on the forces acting on a woman's breast and on the mechanical properties of the breast tissues is important for studying the effects of plastic surgery techniques for breast reconstruction as well as for the design of cosmetic breast implants. Surprisingly, there are no data in the literature regarding mechanical loads on the breast tissues during daily or sport activities, and there are no coherent sources of data in regard to mechanical properties of the breast tissues. Accordingly, this paper is aimed at reviewing the mechanics of the normal breast. First, the anatomy of the breast and major aging-related changes are described. Second, the mechanical characteristics of all tissue components of the breast are detailed. Last, analytical approximations are made in regard to the forces acting on the breast during normal activity, and the respective internal breast forces supported by the suspensory ligaments, pectoralis fascia and ribs are calculated. The data presented in this paper are useful for biomechanical modeling of the breast as well as for evaluating the loads acting on surgical repairs and breast implants.