Dr. Michael K. Newman, MD

Breast Augmentation: Under vs Over the Muscle

One of the most important decisions in breast augmentation surgery — and one that is often misunderstood. Here is how to think about implant placement based on your anatomy and goals.

2Primary placement options
60–70%Of augmentations use submuscular placement
1 yrFor final, settled appearance
AnatomyThe only real determinant

The Two Placements Explained

Breast implant placement refers to where the implant sits relative to the pectoralis major muscle — the large chest muscle that runs from your sternum to your upper arm. There are two primary options, each with meaningful differences in how they feel, look, and behave over time.

Submuscular (Under the Muscle)

The implant is placed beneath the pectoralis major muscle. More precisely, in the most common variation of this technique (called dual-plane placement), the upper portion of the implant sits under the muscle while the lower pole sits beneath the breast gland. This is the most widely used placement in modern breast augmentation.

Subglandular (Over the Muscle)

The implant is placed above the pectoralis major muscle, behind the breast gland. There is no muscle covering the implant. This placement is faster surgically, involves less initial discomfort, and allows the muscle to move freely without affecting the implant. It is the right choice for specific patients and the wrong choice for others.

Subfascial (A Variation on Subglandular)

A third option involves placing the implant beneath the pectoralis fascia — the fibrous tissue that envelops the muscle — but above the muscle itself. This provides a thin extra layer of tissue coverage compared to pure subglandular placement. It is not widely adopted and the evidence for meaningful clinical benefit over standard subglandular placement is limited. Dr. Newman evaluates this option on a case-by-case basis when relevant.

How Anatomy Drives the Decision

The single most important factor in placement selection is the amount of natural breast tissue you have, specifically the thickness of the tissue over the upper pole of the breast. This determines whether you have sufficient native tissue to create a natural-looking result over an implant without muscle coverage.

The Pinch Test

During consultation, Dr. Newman performs a pinch test on the upper pole: pinching the tissue at the top of the breast between thumb and forefinger. If this measurement is less than 2 centimeters, there is insufficient tissue to adequately cover an implant in the subglandular position. In this scenario, the edges of the implant would be visible or palpable, particularly in the upper inner portion of the breast, and the result would look artificial. Submuscular placement uses the pectoralis muscle as an additional layer of coverage.

If the pinch test shows 2 centimeters or more, subglandular placement may be appropriate depending on other factors including the patient's aesthetic goals and lifestyle.

When Submuscular Placement Is Recommended

Submuscular placement is typically the right choice when:

When Subglandular Placement Is Recommended

Subglandular placement is typically the right choice when:

A Common Misconception: Many patients ask for "over the muscle" because they have heard it looks more natural or because they want to avoid muscle pain. The reality is that for patients with thin tissue, subglandular placement produces a less natural result — the implant edges become visible and the surface has an artificial appearance. For the right patient with adequate tissue, subglandular can look completely natural. The question is always whether your anatomy supports it, not which option sounds better in the abstract.

The Dual-Plane Technique

The most widely used variation of submuscular placement in modern breast augmentation is the dual-plane technique, developed by Dr. John Tebbetts. Rather than placing the implant entirely behind the muscle (which creates an unnaturally high, tight appearance), the dual-plane technique releases part of the lower pectoralis muscle so that the implant occupies a pocket that is partially submuscular (upper) and partially subglandular (lower).

The result is a more natural lower pole shape with better projection at the breast crease, while still benefiting from the muscle coverage in the upper pole where rippling and visibility are most common. The dual-plane technique has become the default for most submuscular placements and is the approach Dr. Newman uses for the majority of his augmentation patients who are candidates for submuscular placement.

Animation Deformity: The Key Trade-Off for Active Patients

When the pectoralis major muscle contracts — during push-ups, chest press exercises, gymnastics, swimming, or even certain yoga poses — it pulls on the tissue above and below it. With a submuscular implant, this contraction temporarily moves or distorts the shape of the implant. This is called animation deformity or dynamic deformity.

Animation deformity is visible only during muscle contraction and does not affect the resting appearance or long-term outcome. For most patients, it is a minor inconvenience. For competitive athletes, dancers, or patients in professions where their chest is visible during physical performance, it may be a more significant consideration.

The degree of animation deformity varies by patient and is influenced by implant size (larger implants show more movement), implant profile, and the individual's muscle anatomy. A thorough consultation will include a realistic discussion of what animation deformity might look like for your specific anatomy and activity level.

Comparing Outcomes: A Direct Summary

FactorSubmuscular (Under)Subglandular (Over)
Best for thin tissueYes — muscle adds coverageNo — edges may show
Best for active athletesDepends on sportYes — no animation
Upper pole appearanceNatural slopeFuller, rounder upper pole
Recovery comfortMore initial tightnessLess initial discomfort
Rippling visibility riskLower (muscle coverage)Higher (in thin patients)
Animation deformityPresent during contractionNone
Capsular contracture riskSlightly lowerSlightly higher
MammographyMore tissue visibleSlightly less tissue visible
Surgical timeLongerShorter
Sagging correctionLimited without liftCan fill lower breast envelope

Capsular Contracture and Placement

Capsular contracture — the hardening and tightening of scar tissue around the implant — is one of the most common complications in breast augmentation. Research suggests a slightly lower rate of capsular contracture with submuscular placement, likely because the muscle's movement creates a massage effect that may help prevent the capsule from hardening. The difference is not dramatic, but it is an additional point in favor of submuscular placement when anatomy supports either option.

Implant Type and Placement Interaction

The decision between submuscular and subglandular placement also interacts with implant type selection. Highly cohesive gel implants (gummy bear implants) have a firmer consistency that reduces the visible rippling that can occur with saline or standard silicone implants in the subglandular position. This means that a patient who might show rippling in subglandular placement with a standard silicone implant might be a better candidate for subglandular placement with a highly cohesive gel — an option worth discussing in consultation.

What Happens at a Consultation

The placement conversation happens as part of a broader evaluation of your goals, anatomy, and implant selection. Dr. Newman's consultations cover:

Placement is not a patient preference decision made in isolation — it is a surgical recommendation based on physical findings, with the patient's goals and preferences incorporated into the recommendation.

Schedule a Consultation

Implant placement is determined by your anatomy — and the right recommendation requires a physical examination. Dr. Newman's consultations include 3D imaging and a specific, explained recommendation for your unique anatomy and goals.

Request a Consultation

Frequently Asked Questions

Is under the muscle or over the muscle better for breast augmentation?
Neither placement is universally better. The right choice depends on your anatomy: how much natural breast tissue you have, your chest wall structure, your lifestyle, and your aesthetic goals. Patients with thin tissue coverage typically benefit from submuscular placement for a more natural appearance. Patients with adequate tissue coverage and active lifestyles may prefer subglandular placement to avoid animation deformity. A thorough physical examination is required to determine which approach is appropriate for your specific body.
Does under the muscle placement hurt more?
Submuscular placement does involve more initial discomfort than subglandular placement because the pectoralis major muscle must be elevated and stretched around the implant. Most patients describe a tight, pressure-like sensation for the first week. With modern pain management protocols, this is well-controlled and typically resolves within 10 to 14 days. Subglandular patients typically have less initial soreness but similar recovery timelines overall.
Will breast implants interfere with mammograms?
Breast implants require modified mammogram technique (Eklund views) regardless of placement. Submuscular implants are often considered more mammography-friendly because the pectoralis muscle partially shields the implant, allowing more breast tissue to be visualized with displacement views. You should always inform your mammography technologist that you have implants so they use the proper technique.
What is animation deformity?
Animation deformity occurs with submuscular implant placement when the pectoralis major muscle contracts during activity, causing the implant to temporarily move or distort its shape. This is most visible during push-ups, chest press exercises, or any motion that engages the pectoralis. It is more visible in patients with larger implants and less tissue coverage. The degree of animation varies by patient and typically does not affect the resting appearance or the long-term outcome of the augmentation.
Can the placement be changed if I am not happy with the results?
Yes, placement can be changed during a revision procedure. Patients who experience significant animation deformity with submuscular implants can have their implants converted to subglandular placement if their tissue coverage supports it. Similarly, patients with subglandular implants who develop rippling or visibility issues can be converted to submuscular placement. Revision surgery is more complex than primary augmentation and typically carries higher surgical complexity and cost.
Does implant placement affect how long implants last?
Placement itself does not determine implant longevity. Implants are not lifetime devices and may need replacement or removal over a patient's lifetime. The FDA recommends MRI screening every two to three years for silicone gel implants to check for silent rupture. Factors that affect longevity include implant type, surgical technique, and the patient's tissue response — not whether the placement is submuscular or subglandular.

Related Reading

Patients exploring breast augmentation often research related wellness and health topics alongside their surgical planning. For patients managing dental health during the perioperative period, The Dental Article provides guidance on oral health considerations. Patients preparing for surgery also frequently consult resources on recovery nutrition — Nature's Zest Nutrition covers a range of wellness and gut health topics relevant to surgical recovery.