Background: Breast implants are capable of making dramatic changes to a women’s breasts. Increases in size with a much fuller shape are typical and expected. Implants achieve these effects by altering the soft tissue through their ability to be stretched and expanded.
But there are certain fixed features of a woman’s chest that may not change with breast implants. One of these features is skeletally-based and is the sternum. The bony separation of a women’s breasts create the natural spacing between them. Implants may expand the soft tissues next to them but they can not make the sternal distance smaller in most cases.
Sternal spacing is one differentiator between breast implants that are placed above or below the muscle. A submuscular implant is blocked by the muscle from encroaching onto the sternum. Conversely implants placed in the subglandular location (above the muscle) can stretch the soft tissues to hang over onto the sternal bone, thus reducing the sternal spacing between the breast mounds.
Case Study: This 28 year-plod female wanted breast implants. She has always had small breasts and was very thin. She has lost what little breast tissue she had after having children. She had a very skeletonized chest with a wide sternum between her small breast mounds.
Under general anesthesia, she has saline breast implants placed through transaxillary incisions. The implants had a base size of 300cc and were inflated to 375ccs. Her wide sternal spacing remained although the enlarged breast mound made it appear somewhat smaller.
It is good preoperative counseling to advise women undergoing breast augmentation that the natural sternal spacing will determine how close their breast mounds will be. This its not under direct surgical control unless one wants to have their implants in the subglandular location.
Highlights:
- Implants change numerous aspects of the breasts but can not do much with wide sternal breast base spacing.
- Submuscular implants are blocked from narrowing a sternal muscle by the medial edge of the pectorals muscle.
- Only subglandular breast implants can narrow the distance between the two edges of the implants in a wide sternum.
Dr. Barry Eppley
Indianapolis, Indiana