Implant Placement Debate: Over vs. Under the Muscle

Over a quarter million women will have a breast augmentation this year alone. When the time comes, one of the biggest decisions that they will need to make is whether to place their implant above or below the muscle. Implant placement can affect not just your aesthetic result, but possibly your health as well.

While most surgeons prefer smooth breast implants placed under the muscle, board certified plastic surgeon Dr. Tracy Pfeifer of New York City is a bit of an outlier. She discusses her somewhat controversial perspective and approach – the relationship between implant placement and capsular contracture, and some guidelines for deciding whether over versus under is right for you.

Historical Context: Over vs. Under 

Patients who come in to see a plastic surgeon for a breast augmentation typically have a lot of questions. There are a good many variables to consider, including:

• breast implant type: saline vs. silicone
• shape: round vs. shaped
• texture: smooth vs. textured
• implant size and fill
• implant placement

Whether to place the breast implant above or below the muscle is one of the more confusing decisions for many patients. In the United States, most plastic surgeons recommend under the muscle, but it is important to have some historical context.

In the early days of breast augmentation surgery, implants were always placed on top of the muscle. Why would you place an implant underneath the muscle when that is not where your breast tissue is located? These procedures involved a high capsular contracture rate; in some studies, it was up to 30%. Surgeons took notice and began really looking for ways to reduce the capsular contracture rates. One of the things that they tried was placing the implant underneath the pectorals major muscle.

The results were positive. Capsular contracture rates were lower when the breast implants were placed under the muscle. That being said, when they did those studies, surgeons didn’t yet know about the bacteria theory of capsular contracture. The surgeons in these studies were not taking the additional steps that are taken now to reduce bacteria.

When Is Over the Muscle Safe?

Some of the latest studies show that, if you take a smooth implant and you place it on top of the muscle, it does have a slightly higher capsular contracture rate. However, if you take a textured implant and place it on top of the muscle, there is not much of difference in the capsular contracture rate. This potentially indicates that the over versus under debate, from a health standpoint, really only applies to smooth implants.

Over vs. Under: Depends on the Patient

For Dr. Pfeifer, “it boils down to what’s going to look good on the patient.” If a patient has very thin tissue in the cleavage area, and the implant is placed above the muscle, there is a strong possibility that the edge of the implant will be visible. Rippling can also be an issue. In these cases, Dr. Pfeifer will place the implant under the muscle because the muscle will act as cover for the implant while still delivering a natural looking result.

Implant Placement & Revision Surgery

“I prefer on top of the muscle because I do a lot of revision surgery,” explains Dr. Pfeifer. She sees a lot of complications from under the muscle implant placement, especially when that implant is smooth. Many surgeons choose to use smooth implants because they feel “super soft.” When you use a smooth implant, the capsule that forms around the implant is also smooth. There is nothing to hold it in place so the implant is free to “tumble” around in the pocket.

Over time, the pocket can stretch and the implant can become displaced. A displaced implant is one that has shifted out of alignment behind the nipple and moved either out or down. This condition gets worse when the smooth implant has been placed under the muscle because every time that you flex your pec, it presses down on the implant. Bottom line, if a patient wants her implants underneath the muscle, Dr. Pfeifer encourages her to use a textured implant to keep it in a more stable position.

Another group of revision patients who really benefit from the implant being placed on top of the muscle are those patients who need a mastopexy, or breast lift. When you lift the skin and breast tissue and place the implant on top of the muscle, the breast tissue and implant are in “the same space and they kind of move together so you don’t get the implant in one position and the breast tissue in another position” says Pfeiffer.

“The advantages of under versus over are really very patient specific and depend a lot on the patient’s tissues and what type of implant the surgeon wants to use.”