Very Little Tissue and Considering a Breast Augmentation: Under or Over the Muscle?

A great question came in from a thin patient: "I have very little breast tissue and I want a breast augmentation. Should I go under the muscle or over?"

This is one of the classic decision points in augmentation, and for thin patients specifically, it's genuinely a pick-your-poison situation. Let me walk through the traditional teaching, why it's changing, and how to actually think about the trade-off.

For decades, the standard way to make this decision has been a simple pinch test:

• The surgeon pinches the tissue in the upper portion of the chest (the upper pole, where the implant will show most)
• If there's more than a certain amount of tissue → recommend under the muscle
• If there's less than a certain amount → recommend over the muscle (or at least offer it as an option)

The logic is about coverage and camouflage.

If you have very little tissue over the implant:

• The edge of the implant becomes more visible — you can see or feel where it starts
• Rippling becomes more visible — the folds in the implant transmit through thin tissue
• Both of these are bothersome for patients aesthetically

Going under the muscle adds a layer of muscle coverage over the upper part of the implant, which helps hide the edge and rippling in thin patients. That's why the traditional teaching pushes thin patients toward submuscular placement.

Here's the important update: a lot of us aren't following these older recommendations as strictly as we used to. Two things have changed.

All of the major implant brands now make more cohesive implants — the modern "gummy bear" generation. These:

• Hold their shape better
• Ripple significantly less than the older, softer implants the pinch-test rule was built around
• Make the "thin tissue = must go under the muscle to hide rippling" logic less compelling than it used to be

So one of the main reasons for the old recommendation — rippling visibility — has been partially solved by better implant technology. (Same theme as why modern technique has changed capsular contracture rates — the field evolves and old rules of thumb get outdated.)

Here's the part that the traditional teaching underweights, and it's especially important for thin patients:

So if you go under the muscle as a thin patient:

• You hide the implant edge a bit, BUT
• You see the muscle movement more prominently
• Every time you flex or move your arms, the thin tissue makes the animation deformity more visible

This is the exact same problem that drove the field to move mastectomy reconstruction patients to prepectoral (over-the-muscle) placement. Reconstruction patients have very little tissue, and they were very bothered by the muscle movement — so we moved them over the muscle.

The same logic applies to thin augmentation patients. A thin patient under the muscle may trade "visible implant edge" for "visible muscle movement" — and many patients find the muscle movement more bothersome.

So here's the honest framing for a thin patient:

	Under the Muscle	Over the Muscle
Implant edge visibility	Better hidden (upper pole)	More visible in thin patients
Rippling visibility	Better hidden	More visible (but modern implants ripple less)
Muscle movement / animation	More visible in thin patients	None
Recovery	More tender	Easier

It really comes down to: would you rather risk seeing the implant a bit more, or seeing the muscle move? There's no universally right answer — it depends on which bothers you more.

Here's the option that often resolves the dilemma, and it's worth knowing about:

Fat grafting over the implant:

• Thickens the tissue layer over the implant
• Does a nice job of masking rippling
• Helps camouflage the implant edge
• Gives you the benefits of over-the-muscle (no animation deformity, easier recovery) while solving the thin-tissue downside

So for a thin patient who wants to avoid animation deformity, the combination of over-the-muscle placement + fat grafting can be an excellent solution — you get the muscle-movement-free result with enough tissue camouflage to hide the implant. I've written more about hiding implant edges in thin patients if you want the deeper dive.

If you're thin and deciding on placement, here's how I'd think it through:

1. What would bother me more — seeing the implant edge/rippling, or seeing muscle movement?
2. How active am I? (Athletes and people who use their chest heavily are more bothered by animation deformity)
3. Am I open to fat grafting to thicken the tissue if I go over the muscle?
4. How much does recovery time matter to me? (Over the muscle is easier)

1. "What does my pinch test show, and what do you recommend based on it?"
2. "Given modern cohesive implants, how much rippling risk do I actually have over the muscle?"
3. "If I go under the muscle, how visible will the animation deformity be on my thin frame?"
4. "Can we use fat grafting to let me go over the muscle and still hide the implant?"
5. "What's the recovery difference between the two for me?"

For context on the broader trend: many surgeons (myself included) have been moving toward over-the-muscle and subfascial placements in general, because:

• Modern implants ripple less
• Patients dislike animation deformity
• Fat grafting can solve the thin-tissue coverage problem
• Recovery is easier

So the old "thin patient = automatically under the muscle" rule is softening across the field. That doesn't mean under the muscle is wrong for thin patients — it's still a great option for many — it just means it's no longer the automatic answer it once was.

For a thin patient considering breast augmentation, the under-vs-over decision is a genuine pick-your-poison trade-off:

• Under the muscle = better hides the implant edge and rippling, BUT more visible muscle movement (animation deformity) on a thin frame
• Over the muscle = no animation deformity and easier recovery, BUT more visible implant edge/rippling — though modern cohesive implants ripple much less than the implants the old rule was built around

The traditional pinch test still has value, but a lot of us aren't following it as strictly anymore because better implants and fat grafting have changed the math.

The key question is: which bothers you more — seeing the implant, or seeing the muscle move? And if you lean over-the-muscle but worry about your thin tissue, fat grafting can give you the best of both worlds.

Like everything in plastic surgery, there's no single correct answer — just options with different pros and cons. The right one depends on your anatomy, your priorities, and what you're willing to trade. Talk it through honestly with your surgeon.