We need to talk about "dual-plane".
March 7, 2022
December 7, 2021
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By Dr. Andrew Campbell-Lloyd

We need to talk about "dual-plane".

For the last 30 years, there has been a prevailing status quo in the use of breast implants.

As a rule, I tend to worry at any idea or practise in Plastic Surgery that assumes "status quo". Our knowledge, our experience, our materials and our science haven’t stopped progressing in the last 30 years; any stagnation of thought therefore is both concerning, and something that as a specialty we should be determined to push against.

Sadly, Plastic Surgery is absolutely overwhelmed dogmatic behaviour.

Our reputation as innovators is, in my opinion, underpinned by a very small number of surgeons; the majority of surgeons simply do what someone else has taught them to do. Very often, surgeons learn something, normally at a formative point in their training, and once this thing is learned, they stop thinking about it. Often, this creates no problem as the techniques and theories of how we treat certain conditions may not have dramatically altered over a given period. But how we perform and manage breast implant procedures is not one of them.

As you can probably appreciate, when there is stagnation of thought, and surgeons persist dogmatically with a certain technique of breast augmentation, but progress in implant technology and the science that explains how certain complications occur continues, there develops a disconnect between the theory and the practice of Plastic Surgery. That disconnect leads to poor outcomes for our patients that might otherwise have been avoided.

So, that brings me to the problem I have with “dual-plane”breast augmentation.

Perhaps the first thing we should discuss is what dual plane really means.

Patients seeking breast implants generally understand the idea that implants can be placed either under or over the Pectoralis major muscle. This is part of the common parlance of breast implants, and it has filtered on Instagram and into the forums and discussion groups that many patients use when researching breast augmentation for themselves. The problem is that one cannot simply present this as a choice of under vs. over as though the two are equivalent.

OK, so let’s get some context. First thing we need is a brief history lesson.

Plastic surgeons started using breast implants in the late1960s. The desire to augment the breast is certainly not new. Compared to the current silicone breast implants on the market, the earliest breast implants were, whilst in some ways dramatically different, in other ways fundamentally the same thing: that is, they were moulded bags of silicone designed to mimic the shape of the breast, with the intention being to place theses devices behind the breast tissue to make the breast larger. Rather logically, surgeons decided that in order to enlarge the breast, the obvious approach would be to make an incision under the breast in the natural breast crease, and then to simply create a space on-top of the Pectoralis major muscle (ie. right behind the breast tissue) and pop that breast implant in. This approach prevailed as breast implant technology progressed through several generations of devices.Ultimately however, surgeons began to wonder at the complications that were almost universal at that time after breast implants had been placed.

The most obvious of those complications were capsular contracture, and rupture.

A few surgeons had started to think about capsular contracture in particular. The early studies demonstrated some of the difficulties we still face in researching capsular contracture – namely, the difficulty in culturing bacteria that live in the capsules. Those difficulties aside, surgeons found the early evidence that capsular contracture is mediated by bacteria within the capsules driving an inflammatory response. This is still an evolving field of study with some of the most important work coming from Australian units in the last few years.

What we also know is that the breast gland is populated (much like sweat glands and the skin in general) by bacteria. The assumption therefore followed that if bacteria drive capsular contracture, and if the breast is populated by bacteria, then logically we should be isolating the implant from the breast gland to avoid contamination. The obvious way to isolate the implant was to place it under the Pec major muscle. Prior to this surgeons had been placing implants under muscle when reconstructing the breast following cancer, so there was some precedent for the idea. But it was already acknowledged at that time that placing an implant totally under muscle was not the best for aesthetic and functional reasons (but this was deemed justifiable after mastectomy for other reasons). So we come to the idea of dual-plane.

Basically what dual-plane means is that the implant is covered by the Pec major muscle only. Because the Pec Major doesn’t extend as far down as the bottom of the implant, it means that the lower half of theimplant is not under muscle, but just sits under the breast tissue.

Already, you can start to see the illogicality creeping in. The idea to isolate the implant from the breast leads to surgeons suggesting that the implant goes under muscle. But putting the implant totally under muscle looks terrible, so lets compromise a little and just put the top of the implant under muscle, but leave the bottom of the implant exposed to the breast tissue that we’re supposed to be isolating the implant from. Right.

Anyway, a bit of very low-quality research tried to suggest that the rates of capsular contracture were less when the dual-plane approach was used. And through a combination of compelling conference presentations, genuine technical nous (it is an inescapable fact that innovators such as Dr Per Heden and others have made very worthwhile contributions to the science and art of breast implant surgery), and a tendency towards group think, we have seen over the last 30 years the absolute dominance of dual-plane techniques and a specialty wide inclination to treat the pre-pectoral pocket as a maligned concept.

Over time, I think a few things then happened.

Surgeons realised that the rates of capsular contracture really weren’t any different in the dual plane pocket. But the narrative shifted to suggest that the dual plane technique offered more natural results. This is an utter absurdity which continues to be repeated ad nauseum, by surgeons and patients alike.

It is abundantly clear that the placement of the implant under the muscle in no way creates a more natural appearance. If a slender lady has implants under the muscle, they will be just as visible as if they are placed over the muscle.

The rise of dual-plane also coincided with the rise of anatomical, form-stable, textured breast implants. The narrative around these implants was also that they created a more natural result, and this is just as false in many respects as the idea that dual-plane creates more natural results. An implant that is appropriately sized, be it round or tear-drop, will create a relatively natural result. An implant that is too large for a patient's frame will always create a fake appearance, regardless of shape. More importantly, when presented with an image of a patient who has had a breast augmentation, a surgeon who is unaware of what implant has been used, will only have a 50:50 chance of guessing what kind of implant a patient has based on their clinical appearance. That is, it is total chance. Any argument about “natural” upper pole or less visible implant edges is artifice.

However, the collision of these two narratives was powerful marketing for the implant companies, for surgeons, and for consumers. When this all kicked off in the 90's, everyone in the breast implant industry was high on the heady mix of glamour, money and the burgeoning pop cultural acceptance of cosmetic enhancement.

Which meant that there were a hell of a lot of breast implants being used.

 

The problems that I see, relating to dual-plane implants:

Animation

The big one is animation. If you have a friend with implants (or if you have them yourself) do the following: put their/your hands on hips, push in hard to activate the Pec muscle, watch what happens. If your friend does it, you’ll see those implants get pushed out, with widening of the cleavage, and a weird distortion of the breast shape. If you do it yourself, you’ll feel it as much as see it.

I have a very simply conceptualisation about this problem. The breast is a thing that sits on top of the Pec muscle. If you want to make the breast larger and still behave like a breast, then whatever you do has to also be on top of the Pec muscle, and it has to work in concert with the breast tissue itself. If you do something under the muscle, then you create a disconnect between the thing you’ve done to enlarge the breast, and the breast itself.

Oh, and you’ve cut a very important muscle, which changes the way it works. Which is bad.

Pain

Pain with breast implants is something I see all the time. I have a sneaky feeling that there are many women with breast implants who have discomforts that they have just chosen to accept. Happy to be proven wrong.

Pain due to cosmetic breast implants is really poorly researched and the cause of pain is poorly defined. I have some thoughts which seem to be consistent with what I see after I revise breast implants.

The basic idea is that pain from breast implants is due to 3 things: muscle stretch, nerve irritation and capsular contracture.

There is an increasing body of literature which attests to cosmetic breast augmentation being a cause of chronic pain in a substantial population of patients. A cursory assessment of the literature would suggest that possibly 40% of women who have a breast augmentation have chronic pain-related symptoms, and reduced physical well-being after cosmetic breast augmentation.

That is a big deal. 40% is not a small number. Why are we not talking about this more?

I genuinely wonder whether the psychology of this kind of surgery leads patients to voluntarily suppress the reporting of these symptoms to their treating surgeons. Could there be a situation where women who choose to have totally elective cosmetic breast enhancement elect not to report long-term pain symptoms?

Is there a denial of discomfort as a kind of wilful self-delusion, so as to avoid creating any form of regret about the surgery they had, given the costs and choices involved? It seems possible. No one wants to experience "buyer regret", and yet we know it is a thing when it comes to cosmetic surgery procedures.

The women that I see for implant removal almost universally report some kind of discomfort but obviously these ladies are self-selecting given their decisions to explant – they typically are able to either acknowledge regret about their decision to have an augmentation, or they are comfortable with the fact that their perspective may have changed from when they first had breast augmentation.

Functional limitations

There is a common sensation that women describe after dual-plane implants. They report a sense of tightness across the chest, and an unpleasant sensation associated with trying to contract the muscle. It isn’t necessarily weakness (although some describe it that way). It isn’t necessarily discomfort, although that too is a problem. It is just the fact that the muscle is trying to act in a certain way after a surgeon has cut about 1/3 of its normal attachment, and that changes the biomechanics of the muscle. Which matters. And people notice it.

Most women with dual-plane implants simply avoid putting themselves in situations where the Pec major needs to contract forcefully.

There are a hell of a lot of movements that require Pec major contraction…so that is an awful lot to be missing out on.

Malposition & Wide cleavage

We have already acknowledged that the normal breast sits on top of the muscle, and that trying to enlarge the breast by putting something under the muscle is at serious risk of creating a disconnect between the breast and the thing being used to enlarge it. This is especially noticeable at the cleavage.

Widening the cleavage is associated with animation, but represents a distinct aesthetic problem.

The breast itself has a “footprint” on the chest – it has natural boundaries. The Pec muscle has boundaries that are far beyond the breast. In the cleavage, the muscle runs over the breast-bone (the sternum). Putting an implant under the muscle to try to create an enhanced cleavage runs the risk of creating a wide cleavage. This is especially notable when the muscle contracts. The muscle fibres over the sternum tighten and push down,which will shift the implant outwards, away from the midline. This leads a wide, flat cleavage with muscle activation, and an unnaturally broad gap between the breasts when static.

Implant animation with Pec muscle activation showing widening of the cleavage.

And so given all of that, here is the kicker: to avoid these problems, and create a more natural appearing cleavage, it is necessary to weaken the muscle by cutting it more extensively along the edge of the sternum.

Let’s be really clear about that:

The only way to make a dual-plane breast augmentation more "natural" and avoid a wide cleavage is to be even more destructive and cut even more muscle.

Right.

 

Where are we at now?

In recent years, we have seen a couple of profound shifts.

One: Textured implants are distinctly on the nose. ALCL has created a real frame-shift in public perceptions of implants.

Two: Breast implant illness has come roaring back, on the tail of the ALCL fiasco. There is a pseudo-scientific movement creating all sorts of problems, and there is a substantial narrative trying to tie the two problems together.

Three: Fitness for women has changed, and involves very different disciplines to the leotard clad aerobics of the 80’s. Women are lifting weights, doing reformer pilates and yoga, running, playing footy and stand-up paddling. All of these activities involve substantial contraction and engagement of the Pec major muscle.

If every time your Pec major contracts, your implants animate, then you have a problem.

Four: Aesthetic trends change, and I think we are starting to see a real push away from breast augmentation for the first time in 30years. This may be partly accounted for by the fact that there are surgical alternatives such as fat transfer, but mostly I think this ties back in to social movements around acceptance and body-positivity. Sure, there are still plenty of big-lipped muppets on Instagram with enormous breasts who have plenty of followers, and there will always be an audience for that sort of thing. But the aspirational quality of big breasts seems to be passing.

The outcome of these shifts is that women are thinking very hard about what they put into their bodies, and many are not prepared to accept functional trade-offs for aesthetics.

 

Conclusions

So, here we are having come full circle. There is something of a shift back towards a balanced approach to the use of breast implants. It is no longer so black & white: the prepectoral/subglandular/subfascial placement of implants is very much on the cards, but there is also a place for dual-plane approaches in carefully selected patients.

For me, having decided not to offer implant-based primary breast augmentation, this is relevant to my revision work. I spend a good part of my life “fixing” the damage done by breast implants, and in particular, fixing the damage done by dual-plane breast implant placement. A standard approach for me is (when women choose to continue with an implant) to perform a “plane-change” –shifting the implant from dual-plane to pre-pectoral – often in conjunction with fat transfer or a mastopexy.

This plane change involves removal of the old devices, total capsulectomy, careful repair of the damaged Pec major muscle and re-creation of the infra-mammary crease (what some surgeons like to call an “internal-bra”– and no, I promise you that no matter what you’ve seen on Instagram, the internal bra is not a trademark of any one surgeon, no matter how hard they try to market it that way).

I guess the important part of all of this is what I then see after I’ve done this repair work. There are a couple of things that really jump out.

1.  There is a substantial functional improvement that comes from removing the implant under the muscle and reattaching the Pec major.

2. There is an improvement for many ladies in their pain and sense of discomfort after their implants are removed. Perhaps even more interesting is the fact that for ladies who choose to keep their implants, there is less pain once the capsules are excised and the muscle is repaired and the implants are replaced in a controlled pocket on top of the Pec major.

Obviously, correcting for things like capsular contracture, malposition, rupture and time or pregnancy related changes in the breast all have a positive impact.

But the fact that there would appear to be quite a large number of ladies simply accepting a reduction in their quality of life as a consequence of having a cosmetic dual-plane breast augmentation is both deeply troubling, and fascinating in equal measure.