Should your breast implants be placed under or over the chest wall muscle?
Dr. Robert Shenker takes us through the process of deciding if a patient’s breast implants should be placed under or over the muscle of their chest wall.
Recently, the American Society of Plastic Surgery published the statistics showing the most common and sought-after cosmetic procedures of 2017. As has been the case for many years, breast augmentation surgery remains the single most common procedure done in North America. It’s popular because it works, it’s safe, and it makes patients happy!
Despite its popularity, breast augmentation is not without controversies. One lingering question is whether a breast implant should be placed above or beneath the muscles of the chest wall.
First of all, it’s important to point out that a breast implant does not get placed in the breast; it gets placed behind the breast. The whole breast is elevated off of the chest wall, and the implant sits behind, or deep to the breast, where it fills the breast skin envelope and projects the whole breast forward.
But what exactly lies deep to the breast, and why does it matter?
Beneath the breast lies the pectoralis major and minor muscles, and then the ribs.
Placing a breast implant under both the breast tissue AND the pectoralis major muscles is a very common way to do the procedure and, in North America, it is safe to say that it remains the standard approach. I have placed hundreds, if not thousands of implants this way. The rationale for placing the implants under the muscle involves four major factors:
- The desired shape and contour of the upper pole of the breast
- The type of implant and its need to be “hidden”
- The body composition of the patient
- The existence of a phenomenon known as a capsular contracture
Let’s examine each of those factors.
Upper Pole Contour
If a woman desires a very gently sloping upper pole of the breast, without a sharp “take off” of the implant, the implant can be placed under the pectoralis major muscle. The muscle will compress the upper part of the implant and produce a more gently sloped contour.
The Need To Hide The Implant
Some implants, such as saline devices are more likely to be palpable and have visible rippling. Hiding those implants under the chest muscles is a necessity!
Some women are very thin and have almost no body fat under their skin. When a woman’s ribs can be easily seen and counted on the upper part of her chest, there is little choice but to employ the chest muscles as camouflage for the breast implants.
Finally, there is capsular contracture to consider. Capsular contracture refers to the formation of a problematic envelope of scar tissue that surrounds breast implants. Traditionally, there was a feeling that placing the breast implant under the pectoralis major muscle could decrease the chances of capsular contracture formation. The scientific support for this actually being true has changed somewhat over the years and the evidence supporting this is becoming increasingly thin as better surgical techniques and better breast implants have become available. The impact of being under the muscle seems somewhat less important than a variety of other surgical and implant-related factors.
Are there disadvantages to placing a breast implant under the chest muscle? There most certainly are! First of all, in order to make space underneath the muscle, several of the strong muscle attachments have to be irreversibly cut. The attachment of the muscle along the ribs, and partway along the breastbone have to be cut. This can cause swelling, bleeding, and muscle spasm. It can also decrease the strength and change direction of pull of the pectoralis major muscle. While this is not usually an issue for most breast augmentation patients, it can be in certain cases.
Very often after a breast augmentation procedure, patients complain that it took a while for the implants to “settle”. What I believe is happening, in this case, is that a patient sees a swollen, tight, and unnaturally elevated pectoralis major muscle in the upper part of the breast. Patients always interpret this as the implants needing to “settle”, but the implants are not artificially high, and have nowhere to settle too! The fullness and swelling in the upper part of the breast is the pectoralis muscle in spasm and swollen from being cut. It takes several weeks and sometimes months for this to resolve. When it does, patients will tell me that their implants have finally “settled”.
One aspect of placing a breast implant under the muscle that often concerns women is something we call implant animation. This refers to the way the pectoralis major muscle compresses, displaces, and alters the shape of a breast implant during muscle contraction. Patients will sometimes notice this while working out, or during other types of physical activity, and in some cases, it can really be disturbing. When the muscle relaxes, the implant almost always goes back to its original shape and position. But over time, with repeated muscular contracture, it’s possible to see implant malposition.
So what about placing the implants underneath the breast tissue, but on top of the muscles of the chest wall? This is an operation I am doing more and more often these days because the need to go under the muscle has been replaced by some newer technologies.
First of all, the occurrence of palpability and rippling with modern day cohesive silicone gel breast implants is almost unheard of. Using the pectoralis major muscle to add a layer of padding to hide unsightly rippling or to prevent the implant from the palpable just simply isn’t needed anymore with the new and improved silicone implants we use today.
As far as achieving a gently sloping, natural appearing contour on the upper part of the chest, I no longer need to rely on the muscle to do that. These days, I employ something called fat grafting, which, in combination with the breast implant, I refer to as a composite breast augmentation; part implant, part fat graft. This is by far my favourite way to do breast augmentation surgery in the modern era.
Composite Breast Augmentation
A composite breast augmentation works like this: I dissect the pocket underneath the breast tissue and leave the chest muscles in their original, undisturbed anatomic position, the way mother nature intended them to be. A moderate or full projecting highly cohesive silicone gel breast implant is then placed in the pocket, which I then close meticulously. At this point, the upper pole of the breast is still a bit unnatural looking, with a very sharp and abrupt takeoff of the implant. I then do a little bit of liposuction from an area the patient and I agreed upon preoperatively, usually from the abdomen or the thighs. I’ll collect a little bit of fat, process it in a very specific way, and then inject it into the upper pole of the breast to artistically contour the area into a smooth, soft, natural appearance. In effect, I will do with the fat exactly what I used to do with the muscle that had to be cut and permanently displaced.
So, I can get the size, shape, and contour that I want using the composite breast augmentation techniques and I no longer have to cut the muscle at all. But what about the issue of capsular contracture?
It turns out that placing the implants above or below the muscle was only a small part of the capsular contracture story. The surgical techniques used and the type of implants used were major contributors to the formation of capsular contracture. While it may still be true that placing the implants above the muscle has a very slightly higher rate of capsular contracture formation, the difference between above the muscle or under the muscle is actually very, very small.
All in All
Of course, there are still a few patients in whom I must use the submuscular technique. Those are the patients who are extremely thin, with very little breast tissue and very little body fat. Those patients have a choice between going above the muscle and having an implant that will look somewhat unnatural, or have a more traditional approach using a submuscular technique. Ultimately, the patient and I have a thorough conversation about the options and a decision is made that best suits every individual’s needs.