Banana Roll Liposuction: Why the Fat Under the Buttock Is Holding It Up, Why Taking It Can Make the Crease Longer, and When the Fold Is Skin Rather Than Fat

The banana roll gets its name from its shape. Stand with your back to a mirror, look over your shoulder, and the crease beneath each buttock is a curved line running from the inner thigh toward the outer thigh. In a lot of bodies there is a second curve just below it: a soft crescent of fat on the back of the upper thigh that follows the crease and bulges slightly beneath it. That crescent is the banana roll. Surgeons call it the infragluteal fat pad or the subgluteal roll. Patients call it the fold that shows in a swimsuit, the line that doubles when they sit on the edge of a bed, and the thing no amount of squatting has changed.

It is a small area. A typical banana roll holds somewhere between a few tablespoons and a small cup of fat per side, and it is often added onto a larger liposuction of the thighs or flanks almost as an afterthought. It is also one of the sites where liposuction is most likely to make the problem worse. The roll sits directly on the gluteal crease, which is one of the lines on the body where the skin is tied down to deeper structures. The fat in and just below that crease helps hold the lower buttock up. Take too much of it, or take it from the wrong layer, and the crease gets longer, the buttock drops, and a second fold forms below the first. That version, the iatrogenic banana roll, is the one plastic surgeons most often see in revision clinics. It is harder to fix than the one the patient came in with.

This piece covers what the banana roll is and the three different problems that look like one, why the fold under the buttock is an anatomical structure and not just a shadow, how a conservative operation is planned and where it stops, what goes wrong, and what the alternatives (a lift, a graft, a cold applicator) can and cannot do.

What a banana roll is, and the three problems that look like one

The short answer: a banana roll is a crescent of subcutaneous fat on the back of the upper thigh directly below the gluteal crease, and the same silhouette can come from three different problems (a true fat deposit, a buttock that has descended onto the thigh, or a previous liposuction that removed the support beneath the crease), and only the first of those is a liposuction problem.

You find the landmarks by touch. The gluteal crease, which anatomists call the infragluteal fold, is the line where the lower edge of the buttock meets the thigh. In a young, firm body it is short: it starts on the inner thigh, curves outward, and fades out about two-thirds of the way across. It does not reach the outer thigh. Beneath it, the skin of the posterior thigh runs down toward the knee. The banana roll is a band of fat in that upper posterior thigh, roughly parallel to the crease, often thickest toward the middle and tapering at both ends. It is superficial and deep fat together, and it tends to run in families and to be more prominent in women, following the same gluteofemoral fat-storage pattern that the piece on saddlebag liposuction describes for the outer thigh.

The same outline has three causes, and telling them apart is most of the consultation:

• The true banana roll. A short, firm crease, a buttock that sits where it should, and a separate pad of fat below the crease that you can pinch between two fingers as a distinct roll. The skin snaps back when pulled. This patient is a candidate for conservative liposuction, and a small one.
• The ptotic buttock. The lower pole of the buttock has descended with age, pregnancy, or weight loss and now rests on the upper thigh, so the "roll" is buttock tissue folding over the crease rather than thigh fat below it. The crease is long, often running out onto the outer thigh, and pinching the roll pulls up buttock with it. Liposuction here removes the only padding under a fold that is already falling, and the buttock drops further. The operation, if there is one, is a lift.
• The iatrogenic banana roll. The patient had liposuction of the outer thigh, the lower buttock, or the back of the thigh, and afterward a fold appeared or deepened below the buttock that was not there before. The support beneath the crease was removed, the crease was disrupted, and the buttock has slid onto the thigh. This is a revision problem, and more liposuction is the wrong answer.

There is also a fourth outline that is not a roll at all. In lipedema, the fat of the hips and thighs builds up symmetrically from the waist to the ankle, it is tender, it bruises easily, and it does not respond to weight loss. The posterior thigh can show a crescent below the buttock as part of that column. As the piece on lipedema and lymph-sparing liposuction explains, this is a different disease with a different operation, and treating it as a cosmetic banana roll misses the diagnosis.

A related point: cellulite is common on the back of the upper thigh, and the dimpling tends to concentrate along the crease. It comes from the fibrous septa that tether the skin, not from the amount of fat, and the piece on cellulite treatment evidence makes the point that removing fat can make those dimples easier to see.

Why the crease is a structure, not a shadow

The short answer: the gluteal crease is created by fibrous connections that run from the skin through the subcutaneous fat to the deep fascia and pelvis, which makes it one of the five zones of adherence on the lower body, and the fat around it helps the lower buttock sit on the thigh the way a cushion sits on a shelf, so removing it is a structural change, not just a volume change.

The anatomy was set out in two papers that every body-contouring surgeon knows. In 1987, Barry Markman and Fritz Barton described the subcutaneous fat of the trunk and legs in Plastic and Reconstructive Surgery as two layers separated by a superficial fascia. The superficial layer is dense, made of small lobules held in tight fibrous compartments. The deep layer is loose, with large lobules and little structure. Localized deposits mostly form in the deep layer, and that is the layer liposuction is designed to thin. In 2001, Rod Rohrich, Robert Smith, Daniel Marcantonio, and Jeffrey Kenkel mapped the "zones of adherence" of the lower body, also in Plastic and Reconstructive Surgery. These are five regions where the superficial fascia is densely attached to the underlying structures and the skin does not glide: the lateral gluteal depression, the gluteal crease, the distal posterior thigh, the mid-medial thigh, and the inferolateral iliotibial tract. Suctioning fat in a zone of adherence does not let the skin re-drape. It dents.

Two of those five zones matter here. The banana roll sits directly below the gluteal crease, which is a zone of adherence, and the lower part of the back of the thigh, toward the knee, is another. That leaves a narrow strip of the upper posterior thigh where the fat can safely be thinned, with a line at the top that must not be crossed.

The crease itself is held by fibrous tissue that runs from the skin of the fold down to the fascia over the hamstring origin and the ischial tuberosity, the bone you sit on. Anatomical dissections describe it as a condensation of fascia, sometimes called a ligament, that behaves like a hammock. The lower buttock fat sits in the hammock and the hammock is anchored to the pelvis. The fat just below the crease and on the medial thigh adds support from underneath. When that fat is removed aggressively, or the fibrous attachments are cut by a cannula passed back and forth through the crease, the hammock loses tension. The buttock drops a few millimeters to a centimeter, the crease lengthens outward and downward, and the skin of the lower buttock now folds over the thigh. That new fold is the iatrogenic banana roll, and it is built from buttock, not from thigh fat.

This is why surgeons who operate on the buttock talk about the crease as something to preserve. In a fat-grafting buttock augmentation, where fat is taken from the flanks and back and injected into the buttock, the banana roll is sometimes suctioned as part of the reshaping. The better practitioners are clear that this is done lightly and below the crease, not in it. The safety debate around that operation (the 2017 task-force estimate of roughly one death in 3,000 cases from fat embolism, and the shift to injecting only above the muscle) is covered in the piece on Brazilian butt lift safety protocols. But a buttock that was made fuller while its crease was weakened will hang lower within a few years, because a heavier buttock is sitting in a looser hammock.

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The fat beneath the buttock is not the problem sitting under the buttock. It is part of what holds the buttock up, and the surgeon who treats it as surplus is removing the shelf and calling it a contour.

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The operation: small volumes, a small cannula, and a line at the top that stays uncrossed

The short answer: conservative banana roll liposuction removes tens of milliliters per side, rarely more than about 150, from the deep layer of the upper posterior thigh, uses cannulas of three millimeters or smaller, works parallel to the crease rather than across it, stays below it, and is finished by pinch and by looking at the patient standing rather than by the volume in the canister.

Planning is done with the patient standing, because lying down moves the buttock off the thigh and makes the roll disappear. The surgeon marks the crease, marks the roll beneath it, and marks the lower edge of the area to be treated, well above the lower posterior thigh. A photograph from behind with the patient relaxed, and a second one with the gluteal muscles squeezed, shows whether the roll lifts with the buttock (suggesting ptosis) or stays where it is (suggesting fat). A good surgeon also looks at the patient bent slightly forward and seated on the edge of a chair, because the roll and the crease change position when the hip flexes, and the result has to hold up in both.

The operation is short, typically done under local tumescent anesthesia or as part of a larger procedure under general anesthesia. Ports are placed within the crease itself or at its outer end, where the scar will be hidden, and sometimes on the inner thigh. The cannula runs in the deep layer, parallel to the crease, fanning across the roll from its ends rather than punching up through the crease. Superficial suction, the technique of working just beneath the skin to encourage it to tighten, is the source of most rippling on the back of the thigh and has no place here; its trade-offs are discussed in the piece on liposuction versus liposculpture. Energy-assisted devices (ultrasound, laser, radiofrequency) are sometimes offered with claims of better skin retraction, and the evidence for that claim, which is modest, is weighed in the piece on VASER versus traditional liposuction.

The endpoint is thickness, not volume. The surgeon pinches the treated area against the neighboring thigh and the other side until it is even, and stops while a layer of fat, roughly a centimeter, remains under the skin. Typical volumes are small: many surgeons describe 50 to 150 milliliters per side as the usual range for an isolated roll. A plan to take several hundred milliliters from a banana roll is either treating a different problem or planning to take too much. The piece on high-definition liposuction makes the broader point that the most skilled liposuction is judged by what is left behind, and this is the site where that applies most literally.

Two structures deserve mention. The sciatic nerve runs deep beneath the gluteal muscles and hamstrings, well below the fat layer, and a cannula in the correct plane does not reach it. The posterior femoral cutaneous nerve, which supplies the skin on the back of the thigh, runs more superficially and can be stretched or bruised, so numbness over the back of the thigh after the operation is common and usually recovers over weeks to months on the pattern described in the piece on numbness after plastic surgery.

Recovery is mostly uneventful and mostly about sitting. The treated area is bruised and swollen for two to three weeks, and because patients sit on it, the first week is uncomfortable in a way that abdominal liposuction is not. A compression garment that extends down the thigh is worn for several weeks, on the evidence weighed in the piece on compression garments. The final contour takes three to six months to appear, as the piece on the swelling timeline describes, and a crease that looks sharp at two weeks can soften or lengthen as swelling settles and the tissues remodel. The honest evaluation happens at six months, standing, from behind.

What goes wrong: the long crease, the double fold, the dent, and the pair that do not match

The short answer: the characteristic complication of banana roll liposuction is overcorrection, which weakens the support beneath the buttock, lengthens the crease, drops the lower buttock onto the thigh, and creates a new or deeper fold; the other complications are contour irregularities, asymmetry, skin that does not retract, and prolonged numbness, while seroma and infection are uncommon at this site.

The long crease is the signature failure. Before the operation, the crease ends about two-thirds of the way across. Afterward, it runs out onto the outer thigh, and sometimes it curves downward at the end. The buttock looks longer and flatter from behind, the "smile" of the lower buttock becomes a frown, and the patient often describes it as looking older. What happened is that the support below the crease was removed and the fibrous attachments were disrupted, so the lower pole of the buttock slid down and out. The same process happens when the saddlebag is suctioned too far up and back, which is why the outer thigh and the banana roll have to be planned together.

The double fold is the next stage. The original crease is still there, but a second fold forms a centimeter or two below it where the descended buttock now rests on the thigh. Patients see it most when standing with their weight on one leg. It is the iatrogenic banana roll, and it looks like the original problem came back, bigger. It did not. It is a different problem, and suctioning it will make it worse again.

The dent is the third. Fat removed unevenly, or too close to the surface, or in the zone of the lower posterior thigh, leaves a groove or a ripple that shows through thin clothing and is visible in a swimsuit. The back of the thigh has thin skin in many patients, and there is little margin for error. Seroma, a collection of fluid under the skin, is covered in the piece on seroma after plastic surgery and is uncommon with small-volume liposuction at this site. Asymmetry is near-universal before the operation (every pair of buttocks is different) and should be photographed and measured beforehand, so that the difference afterward has a baseline to be judged against.

Skin that does not retract is the last. In patients past their forties, after pregnancies, or after major weight loss, the skin of the posterior thigh often lacks the elasticity to shrink over a smaller volume. Removing the roll then leaves a loose, slightly crepey fold in the same place. A pinch-and-snap test at the consultation predicts this better than any device claim, and the honest response to loose skin is that liposuction will deflate the roll without lifting it.

Fixing it: the lift, the graft, and what the cleared device actually does

The short answer: a ptotic buttock or an iatrogenic banana roll is corrected by restoring support (an infragluteal or lower body lift that removes skin and re-anchors the crease, or fat grafting that rebuilds the lost cushion), not by more suction; for a small true roll in good skin, cryolipolysis is FDA-cleared for the fat below the buttocks and removes a modest fraction of it, with a small risk of the opposite effect.

The infragluteal lift, sometimes called a gluteal crease lift, removes a crescent of skin and fat at the crease and re-anchors the lower buttock to the deep fascia, shortening and sharpening the crease. The scar sits in the fold, which is where it is least visible, but it is also where the patient sits, and scars there are under tension every time the hip flexes. They can widen, migrate slightly downward out of the crease over time, and are prone to separation in the first weeks, as the piece on wound dehiscence describes. Surgeons who perform it usually restrict sitting directly on the incision for several weeks. The operation also does nothing for the upper buttock, and in a patient with significant descent, lifting only the crease can make the buttock look shorter and flatter. It suits a limited descent with a well-defined fold.

When descent is broader (after major weight loss, or combined with loose skin on the flanks and outer thighs), the operation is a lower body lift, the circumferential procedure that Ted Lockwood described in 1993 and that the piece on belt lipectomy and the lower body lift covers in detail. The scar runs around the waist rather than in the crease, and it lifts the buttock and outer thighs together by pulling from above. For looseness that is concentrated on the inner thigh, the piece on the medial thigh lift describes the corresponding operation and its scar.

Fat grafting is the other tool, and for an iatrogenic banana roll it is often the first one. Fat taken from another site is injected into the area where too much was removed, rebuilding the cushion beneath the crease and filling the dent. The injections are placed in the subcutaneous layer, and at this site that is both the safe plane and the one that needs rebuilding. Some surgeons combine grafting with release of the scar bands that formed after the first liposuction. A proportion of the grafted fat does not survive, typically somewhere between a third and a half on the numbers discussed in the piece on fat graft survival, so a second session is common. Grafting does not tighten skin, so it works well when the problem is lost volume and poorly when the problem is loose skin. Buttock implants, discussed in the piece on implants versus fat grafting, add volume to the upper buttock and do not correct a fallen crease.

For a small, true banana roll in firm skin, there is one non-surgical option with a specific clearance. Cryolipolysis, the cold-applicator treatment sold as CoolSculpting, was cleared by the Food and Drug Administration for the fat below the buttocks, specifically named as the banana roll, in 2016, adding to its earlier clearances for the flank, abdomen, and thigh. Published series, most sponsored by the manufacturer, report a reduction in the fat layer of roughly a fifth to a quarter per cycle at two to three months, which on a small roll is a few millimeters. Because the treatment works below the crease, does not remove support in the crease itself when applied correctly, and removes fat gradually, it is less likely than aggressive liposuction to lengthen the fold, though a poorly placed applicator can still flatten the lower buttock. The characteristic complication is paradoxical adipose hyperplasia, a firm, enlarged mass of fat in the shape of the applicator that develops months after treatment. It was once described by the manufacturer as roughly one in 20,000 cycles, and a 2018 single-practice series in the Aesthetic Surgery Journal reported it in 0.72 percent of treatments. The treatment for it is liposuction. The broader device menu is weighed in the piece on non-surgical body contouring.

The rest of the non-surgical menu does little here. Injectable deoxycholic acid is approved only for fat beneath the chin. Biostimulatory injections into the buttock, discussed in the piece on the non-surgical BBL, add a small amount of volume and firmness to the buttock and do not remove a fold beneath it. Exercise builds the gluteal and hamstring muscles, which can improve the shape of the buttock above the crease, but it does not reduce a fat deposit below it. Fat that is removed by liposuction does not return to the same site unless weight is regained, as the piece on whether fat comes back after liposuction explains, and weight regained after the operation tends to go elsewhere.

The honest summary

The banana roll is a crescent of fat on the back of the upper thigh just below the buttock crease. It is small, it is common, and it is one of the sites where liposuction most often makes the problem worse. The crease above it is a zone of adherence: fibrous tissue ties the skin to the pelvis, and the fat in and below the crease helps hold the lower buttock up. A true roll, a firm pad of fat below a short crease in skin that snaps back, can be thinned by conservative liposuction: tens of milliliters per side, a small cannula, the deep layer only, strokes parallel to the crease, and a line at the top that the cannula does not cross. A roll made by a descended buttock, or created by an earlier liposuction, is a support problem, and more suction lengthens the crease, drops the buttock, and deepens the second fold. Those patients need a lift (at the crease for limited descent, around the waist for broader descent) or fat grafting to rebuild the cushion. Cryolipolysis is cleared for this exact site and removes a few millimeters, with a small risk of adding a lump. Before booking, ask the surgeon to say which of the three problems you have, where they will stop, and roughly how much they will take out. Then ask to see standing photographs from behind at six months. If the crease in those photographs is longer than it was before, the operation failed, however smooth the thigh beneath it looks.