Hip Dips & the Gluteal Frame: Fat Grafting and Custom Hip Implants

Two people can carry the same weight on the same frame and have completely different silhouettes. The difference is rarely size — it is the shape of the gluteal frame: where the waist narrows, where the hip carries volume, and whether the outer hip dips inward or curves outward. A Brazilian Butt Lift (BBL) is often described as "making the buttock bigger." In practice, the result patients respond to is usually a matter of contour: removing fat that flattens the frame, and adding fat where it builds the curve — including the hip dips.

This article focuses on the part of gluteal contouring that gets the least clear explanation online: hip dips and the lateral gluteal frame. It draws on Dr. Robert J. Troell's 2026 peer-reviewed study of 112 women who underwent VASER ultrasound-assisted liposuction with stem cell–enriched fat grafting to the buttocks and hip dips (Medical Research Archives, 14:4, DOI 10.18103/mra.v14i4.7467), and on his published work on aesthetic hip implants — a structural option for hip dips that fat alone cannot correct (Aesthetic Surgery Journal, 2022, DOI 10.1093/asj/sjac064). The figures above are averages from that 112-patient series and describe one surgeon's protocol; they are not a promise of any individual result.

"Hip dips" — the inward depressions along the outer hip, just below the hip bone — are a normal feature of human anatomy, not a sign of being overweight or out of shape. They sit at the point where the outer edge of the pelvis meets the soft tissue of the upper thigh, over a depression near the greater trochanter (the bony prominence at the top of the thigh bone). Many people have them at every weight they have ever been, because their origin is partly skeletal: the width of the pelvis, the position of the hip bone, and the way muscle and fat drape over that structure.

That skeletal contribution is the key to understanding which hip dips respond to which treatment. Clinically, it is useful to separate two patterns:

• Soft-tissue-dominant hip dips. The depression is mostly a relative lack of fat and soft tissue over the outer hip, framed by fuller areas above and below. These tend to fill predictably with fat grafting.
• Structurally-dominant hip dips. The depression is driven more by the underlying bony anatomy than by a soft-tissue deficit. These can be softened with fat, but a deep, bony hip dip may not fully correct with fat alone — which is where a custom implant enters the conversation (covered below).

The distinction is made at consultation, using standing photographs in multiple views, palpation of the area, and a discussion of goals. There is no single answer that fits everyone — the honest version of this conversation includes telling some patients that fat grafting will improve a hip dip rather than erase it.

The most common misunderstanding about gluteal contouring is that it is purely additive. It is not. The curved, "heart-shaped" silhouette many patients describe is created as much by where fat is removed as by where it is added. Removing fat from the lower back and flanks narrows the waist and exposes the upper curve of the buttock; the outer hip and mid-buttock are then built up; and the result reads as an A-frame.

In the 2026 study, this was done in one 360-degree session: fat removed from the lower back, flanks, and frequently the inner and outer thighs to frame the buttock, then re-injected into the buttock and hip dips to build the curve (DOI 10.18103/mra.v14i4.7467). The lower-back and flank reduction is not optional polish — in the surgeon's description, framing those areas is what allows the buttock to read as lifted and projected. The female aesthetic the technique targets is often described as an inverted heart shape, with a small triangle of space defined between the inner thighs and the lower curve of the buttocks.

This is also why hip dips and buttock projection are planned together rather than separately. Filling a hip dip without addressing the waist and flanks can widen the silhouette instead of curving it; narrowing the waist without addressing the outer hip can leave the dip looking deeper. The frame is designed as one shape.

The honest answer is that not all of it stays — and a good technique is built around that fact. Grafted fat that fails to establish a blood supply in the first days is reabsorbed by the body. The technique's job is to maximize the share that survives. Two numbers describe how this protocol approaches it:

• Processing yield. Centrifugation-filtration concentrates the harvested fat down to roughly 60% of its raw volume by removing fluid, oil, and damaged cells. What is injected is compacted, purified fat — so less volume is needed for the same result, and the injected fat is of higher quality.
• Retention. In the published evidence cited in the 2026 study, ultrasound measurement documented 75–85% volume retention at seven months after injection (DOI 10.18103/mra.v14i4.7467). Long-term data from Coleman shows that once grafted fat stabilizes — typically by 2–3 months — the surviving volume remains stable for years.

The PRP and adipose-derived stem cell enrichment is aimed squarely at this survival window: both promote the new blood-vessel growth (neovascularization) that determines which fat cells live past the first 1–2 days. It is also why the surgeon does not overfill — pushing more fat into the subcutaneous space than it can support raises the pressure on the grafted cells and lowers survival, the opposite of the goal. The durability of a well-executed graft is real: the 2026 paper documents a patient followed for eight years with a maintained result.

Hip and gluteal fat grafting depends on two things the patient brings to the table: enough donor fat to harvest, and a realistic understanding of what reshaping the frame can and cannot do. A very lean patient may not have the donor volume for a large change; a patient well above their ideal body weight is usually advised to optimize weight first, both for safety and because the result is more stable at a steady weight.

In the 2026 protocol, candidacy and preparation included:

• Weight optimization. Patients were encouraged to be at or near their ideal body weight; those above it were counseled on a weight-loss trial before contouring.
• Medication review. Drugs that interfere with the liver enzyme that clears the local anesthetic (cytochrome P-450 inhibitors — certain antidepressants, blood-pressure medications, antifungals, and others) lower the safe anesthetic dose and are reviewed in advance.
• Hormone and GLP-1 timing. Oral estradiol was stopped at least two weeks before surgery to lower clot risk; GLP-1 weight-loss medications were stopped two weeks before as well.
• Smoking and vaping cessation. Stopping at least 2–3 weeks before and continuing after surgery to lower infection risk and protect fat survival.

Patients who request general anesthesia, who want a silastic gluteal or hip implant, or whose goals exceed what the subcutaneous space can safely hold in one session may be referred, staged, or counseled toward a different plan. Patient selection is itself part of the safety of the procedure — the favorable outcomes in any published series reflect, in part, who was chosen to operate on.

Hip and gluteal contouring sits at the intersection of two things that are hard to find in one surgeon: a safety-first liposuction-and-fat-grafting protocol, and genuine experience with the structural options — custom hip implants — for the hip dips that fat cannot fully correct. Dr. Robert J. Troell is board-certified in cosmetic surgery and in facial plastic & reconstructive surgery, with more than 30 years of surgical experience, and has published peer-reviewed work across this exact territory: the 2026 gluteal and hip fat-grafting series (DOI 10.18103/mra.v14i4.7467), the 2022 aesthetic hip-implant paper in the Aesthetic Surgery Journal (DOI 10.1093/asj/sjac064), and a body of liposuction and fat-grafting research spanning two decades.

That published record is not a marketing detail — it is the difference between a surgeon who follows the contouring literature and one who contributes to it. When you are choosing where to have a procedure as technique-dependent as this one, the substance of the consultation matters more than the size of the promise.