On the left, the breast implant is shown above the pectoralis major muscle. On the right, the implant is under the pectoralis major muscle. Note that the muscle on the right is cut or "released". This allows the implant to settle nicely to the base of the breast. Also note that the outer part of the breast implant on the right has no muscle coverage.
Once you have chosen an incision, the next key decision for your breast augmentation is whether to place the breast implants "under or over the muscle".
The muscle referred to here is the pectoralis major. Both subpectoral and subglandular pockets are widely used by plastic surgeons, but subpectoral placement is the most common current approach.
Tissue is Needed To Cover Breast Implants
There are a few key issues about this choice, but in our opinion the most important one is the thickness of your tissues and our ability to hide the edges (including ripples) of the breast implants with your soft tissue coverage.
There are basically three layers of soft tissue making up the breast: the outer layer is skin; the middle layer is fat and connective tissue; and the deep layer is the breast gland itself. When considering your soft tissues in relation to breast augmentation, think of them as the breast tissue padding that is available to cover implants.
This example of a mastopexy and breast augmentation demonstrates a dual-plane approach to the soft tissue coverage over a breast implant. On the right, the pectoralis major muscle has been released at the base of the breast and has retracted upward. In time, after the implant has settled into the base of the breast, only the upper third of the implant will be covered with muscle and the lower two-thirds of the implant will be covered with breast tissue and fat. The implant coverage with the muscle is adjusted on a case-by-case basis depending of the anatomy of each breast augmentation patient.
Muscle Can Cover Breast Implants
The pectoralis major is a long, wide, triangular-shaped muscle that begins along the entire breastbone and the ribs at the base of the breast and inserts into the humerus at the upper arm. This muscle is a thick (about 1/4- 1/2 inches) and strong layer of soft tissue which can provide very significant padding over breast implants.
Women With Thick Breast Tissue Padding
In women with thick layers of breast skin, fat and glandular tissue there is good padding to cover breast implants. In such women, the additional padding provided by the pectoralis major muscle may not be critical.
Women With Thin Breast Tissue Padding
Many patients' tissues are thin enough that there is a risk of breast implant visibility or palpability, especially over time. Therefore, for most women it is desirable to cover the implants with as much soft tissue as possible. The pectoralis major muscle is dense tissue that usually provides excellent additional soft tissue padding over the breast implants.
Unfortunately, since the muscle is triangular-shaped, it does not cover the entire breast implant (see figure below). However, the pectoralis major does cover the implant in the most important areas, the upper and middle parts of the breast and the cleavage area. These areas of the breast are the most important areas to have optimal soft tissue padding and protection against implant ripples, since these are the areas that may be exposed if you wear a low-cut top or bikini. Unfortunately, subpectoral placement will not protect you from visible rippling of the breast implants at the sides of the breasts where breast tissue is absent and the skin and fat layers are the only padding over the implants. Fortunately, the sides of the breasts are easy to cover with a bra or bikini top, so if visible rippling occurs it is usually concealed in clothing.
Muscle Coverage At The Base Of The Breast
The figures above illustrate another important feature of muscle coverage. In most cases, the muscle does not cover approximately the lower 1/5th of the breast implant. This occurs because the surgical plan usually includes cutting the muscle near the lower rib margin. Once cut, the pectoralis muscle usually retracts 1-2 inches upward. This leaves the lower poles of the breast implants with only breast and fatty tissue coverage.
Adjustments In Muscle Position
In some women it is desirable to adjust the muscle position so that only _ or 1/3rd of the upper part of the implants are covered with the pectoralis muscle. Patients that often benefit with such a "half and half" approach to the muscle are those with mildly sagging breasts or those with tight, constricted breasts. Such surgical adjustments in muscle position are also known as "dual-plane" techniques. In select patients, the dual-plane technique preserves the advantages of subpectoral augmentation in the upper and inner areas of the breasts, while providing the advantages of having the implants directly under the breast gland in the lower part of the breast.
Breast Implant Type And Need For Tissue Padding
During your consultation, Dr. Connall will measure your soft tissue thickness and advise you on breast implant placement location. Except in rare cases in which one has very thick soft tissues, we prefer to place saline breast implants under the pectoralis major muscle. This is because the saline breast implants themselves have significant ripples. To minimize the risk of having visible ripples of the breasts, essentially as much soft tissue padding as possible is needed to cover the implants.
Silicone breast implants ripple less than saline implants and are more forgiving in terms of causing visible rippling of the breasts. Therefore, silicone gel breast implants can be placed above the pectoralis major safely in more cases compared to saline implants. However, we recommend subpectoral placement in most cases of silicone gel augmentation too, simply because this placement affords many advantages and few, if any, significant disadvantages compared with subglandular placement.
This image shows the breast in cross-section with a breast implant in the subpectoral space, under the pectoralis major muscle. Note that the muscle does not cover the lower part of the implant. The implant is held in position at the base of the breast with the support of the skin and fatty connective tissue, not the muscle.
More Advantages To Subpectoral Implants
There are additional issues to consider regarding breast implant placement. A key advantage to subpectoral placement relates to imaging the breasts for breast cancer screening. Though implants in both positions have some adverse effect on imaging the breasts, it is generally accepted that subpectoral breast implants interfere less with mammography, compared with subglandular breast implants.
In addition, some data suggest that subpectoral implants lead to a lower risk of capsular contracture formation, compared with subglandular implants.
Many of our patients prefer the aesthetics of subpectoral breast implants, as the upper poles of the breasts often appear more naturally sloped, and the upper and inner parts of the breast appear less bubble-like, compared to breasts with subglandular breast implants.
Disadvantages Of Subpectoral Breast Implants
With breast implants under the muscle, movement of the implants and breasts with flexion of the pectoralis muscle will occur to some degree. In our patients, since the lower part of the muscle is cut, the displacement is generally not severe and is not bothersome. Indeed, we usually place the implants under the muscle even in body builders.
Subpectoral augmentation is more painful than subglandular augmentation. But, the difference is not great and is only a factor in the first few days after breast augmentation surgery.
This image shows in cross-section a breast implant in the subglandular space, above the pectoralis major muscle.
Advantages Of Subglandular Breast Implants
Post-operative pain can be less with subglandular breast augmentation compared to subpectoral breast augmentation. However, in our patients the difference in pain is only significant in the first few days after surgery. Since our patients do so well with pain control after subpectoral augmentation, we generally do not feel this should be a major decision point for patients.
In some cases subglandular placement can help improve the shape and position of the breasts following breast augmentation. This is particularly important in women with mildly sagging breasts or tight, constricted breasts. In such patients we generally will perform a "half and half", dual-plane positioning of the muscle, rather than use the subglandular position entirely.
Some patients desire a very round, augmented look. Placement of implants in the subglandular position can help create this look.
Disadvantages Of Subglandular Breast Implants
There is an increased risk of visible implant ripples, especially in those with saline breast implants. There is an increased risk of seeing the edges of the breast implants and a "bubble-like", round look. The breast implants likely interfere more with mammograms if the implants are in the subglandular position, as compared to the subpectoral position. Future breast surgery for removal of suspicious breast lumps or for cancer is more difficult with breast implants in the subglandular position.
During your consultation, Dr. Connall will measure your soft tissue thickness and advise you on breast implant placement location. Be assured, this is a straightforward decision making process and we will be certain that you understand and feel comfortable with our recommendations for you and your decision.