Buttocks Contouring

Aesthetic surgery of the buttocks encompasses many forms. Patients may seek to enhance buttock shape with buttock implants, autologous fat transfer, autologous tissue flaps, excisional procedures, or liposuction. Patients with traumatic buttock injuries and contour deformities from injections also require reconstruction, often with fat injections, autologous tissue flaps, and alloplastic implants. The dramatic increase in body contouring after massive loss associated with bariatric surgical treatments for obesity has also extended to buttock contouring. Skeletal and weight loss–associated gluteal deformities are often severe in nature and have also increased interest in these procedures.

The function of the buttock musculature in stability and gait is an important consideration and often has an impact on the procedure chosen for correction in reconstructive procedures. Its impact on aesthetic procedures is less clinically relevant. The history, definition, frequency, etiology, pathophysiology, clinical presentation, aesthetics, classification, and surgical treatment options are discussed in this article.

Throughout history, artistic endeavors have documented our preoccupation with the human form as a representation of femininity and fecundity. Careful analysis, mathematical interpretation, and recreation of the human form have remained popular pursuits. Recent studies in evolutionary biology have suggested a strong correlation between the "hour-glass" figure and not only female reproductive potential but also general physical health and psychological health. This correlation is best summarized by an ideal waist-to-hip ratio of 0.7 that transcends cultures, is temporally stable, and is cross-generational. The callipygian form best represents this history.

Buttock contour surgery, in contrast, has a short history compared with the field of plastic surgery or art history. Pressure sores and traumatic deformities of this area have been treated for some time, but buttock contour improvement has become an acceptable and frequent request as demands for body improvement have increased. Patients' desire to look their best and the increased safety of liposuction and other body contouring techniques have dramatically increased the awareness of contour problems of the buttock. Recently, demographic changes in the United States coupled with changing societal fashion preferences, codification of aesthetic norms, as well as procedural improvements have increased interest in buttock contouring surgery by patients and surgeons alike.

The first reported attempts to surgically contour the buttock region in the medical literature were described by Bartels and colleagues in 1969. A mammary implant was placed unilaterally in the subcutaneous plane of the gluteal region to correct a deformity. This was closely followed by bilateral placement for aesthetic correction of platypygia. Problems associated with implant migration, capsular contracture, and migration quickly led to alternative placement in a submuscular plane between the gluteus maximus muscle and the gluteus medius muscle. A small submuscular space and anatomic constraints limited significant augmentation with a round implant. The inherent limitations of this procedure led to the development of intramuscular as well as subfascial planes for gluteal contouring with both silicone gel and silicone elastomer implants with more anatomic shapes.

Contemporaneously, liposuction emerged as the most popular body contouring technique. Liposuction was used to reduce the accumulation of fat in all regions of the body. Specifically, it was successfully applied to the flanks and back and the surrounding aesthetic units of the gluteal region. The success of these interventions in improving buttock contouring quickly led to its adoption as the primary form of contouring this region. Increasing reports of success with autologous fat transfer techniques and the popularity of liposuction led to adoption of aesthetic gluteal contouring with fat injections. The popularity of fat grafting in the buttock region has grown, including such specific methods and names such as "Brazilian butt lift" and others, all designed to enhance the shape of the buttocks using fat grafting techniques.[1]

The dramatic increase in body contouring after massive weight loss associated with bariatric surgical treatments for obesity has extended to buttock contouring. These severe deformities have accelerated the recent development of various autologous tissue flaps and excisional body contouring procedures to treat this patient population. The limitation of implant design availability in the United States and associated complications have limited the widespread adoption of implant augmentation of the gluteal region.

Buttock contour defects are common, and patients often seek some form of correction. The treatment choices must match the patient's concerns while not interfering with the necessary function of this area. Long-term approaches are an important consideration, as are scarring and unreasonable expectations. The patient may be concerned with a cellulite-contour irregularity of the skin and desire correction that may not be obtainable. Superficial corrections should be performed with great care to avoid further contour irregularities and detachment of the skin from underlying structures. The inferior fullness below the infragluteal crease or fold is one problem area. Many patients seek contouring of this area, yet excess removal may result in buttock ptosis, which is difficult to correct.

Patients seeking augmentation or enhancement of the buttock should recognize the consequences of implants that are required to withstand a person's weight and activity requirements. The same concerns apply to corrections of traumatic depressions and treatment by fat injections. Lastly, a round buttock with a convex surface demonstrates a groove and depression if a scar crosses the convexity. Restoring the projection and smooth characteristics of the buttock is difficult when normal curvature is distorted.

Frequency

According to The Aesthetic Society, in 2021 there were an estimated 61,387 buttock augmentation procedures (fat grafts and implants) in the United States, a 37% increase from 2020.[2]

The etiology of buttock contour defects can be genetic, traumatic, or acquired. A disproportionately large buttock significantly affects some young men and women; often, these persons are unable to wear fitted clothes or participate in desired activities. The genetically absent buttock (often as significant a genetic defect as a disproportionately large buttock) is also equally undesirable because it does not adequately fill out clothing. Uncommonly, genetic lipodystrophies also affect the gluteal region.

Traumatic defects of the buttock that produce contour problems obscure the curve of the buttock and often create a notch or groove that is clearly visible in swimwear and knit fabric clothes. The patient seeks correction and states a desire to return to the preinjury form. Automobile and workplace accidents and animal bites are common etiologies of contour defects. Iatrogenic deformities caused by failure to accurately repair all anatomic layers during surgical procedures in the trochanteric and gluteal region are also commonly seen.

A scar or defect that crosses the curvature of the buttock usually leaves a depression and groove that requires some form of correction. Furthermore, contour irregularities and overresection associated with liposuction are common causes of gluteal deformities. The authors still see patients with depressions from steroid injections and undrained, resolving hematomas of the buttock. Gluteal compartment syndrome is also a rare but serious clinical condition associated with traumatic injuries.

Acquired gluteal deformities are often associated with aging, menopause, weight gain, sun damage, skeletal deformities associated with obesity, and massive weight loss associated with bariatric surgical procedures. Aging, sun damage, and massive weight loss usually lead to skin laxity and buttock ptosis. Menopause and skeletal changes associated with obesity usually leads to a diminished gluteal aesthetic that is more refractory to surgical interventions.

The pathophysiology of the traumatic defect is relatively simple. A hematoma that remains unrecognized produces a pressure point from within, which reduces the normal fat levels of the buttock form. When the hematoma is drained or resorbed, a depression remains. Traumatic defects from loss of tissue that is either surgically closed or allowed to secondarily resolve often result in contour irregularities. Steroid injections placed within the fatty portion of the buttock can cause absorption and atrophy of fat cells, which also produce a marked depression and thinning of the skin.

Contour defects of the buttock include the above conditions and genetic increases, decreases, and asymmetries that reflect society's range of shapes.

The patient seeks a plastic surgeon to correct contour deformities of the buttock. The discussion may involve an overly large buttock or a buttock that does not adequately fill out jeans. The range of superficial contour irregularities, from an absent buttock crease or infrabuttock fold to a square buttock, also may include the patient declaring that his or her cellulite creates an uneven and unsmooth buttock. The surgeon should listen intently to the patient's comments and expectations of results.

Often, patients seeking liposculpture of the body ask about the buttock, unaware of the many possibilities of correction available to reshape the buttock. Emphasize and discuss the proportions of the patient, and attempt to maintain the patient within a proportional frame.

The large buttock that severely affects a young woman, preventing her from feeling comfortable in swimwear and knit clothing, and the small buttock that prevents the patient from filling out jeans are examples of culture's negative physiques. The patient may vocalize more on the superficial components of the buttock shape with absent definition and asymmetry. The surgeon must be cautious about specific demands regarding a matched symmetric shape.

Indications for treatment include a prominent, deficient, or misshapen buttock. As expertise in minute corrections has improved, indications have also increased to allow minor asymmetries, absent creases and folds, and square shapes. All of the above situations are appropriate indications for treatment.

Use caution with superficial irregularities that are more confined to the skin and superficial levels. The patient may describe this as cellulite. Many attempts to correct these deformities have failed and may actually worsen the other initial defects. Caution also must be emphasized concerning the fullness just inferior and parallel to the buttock (the so-called banana deformity). Many patients seek liposuction of this area to create a better fold and contour. However, this area often supports the buttock, and removal leads to further ptosis that is difficult to correct. The surgeon must be cautious in accepting these indications for treatment.

Common indications include large and prominent buttocks, deficient and flat buttocks, lack of or an uneven buttock crease and fold, depressions in the buttock, square buttock shapes, and an irregularly shaped buttock. Possible indications include superficial irregularities and asymmetric or uneven minor ptosis of the buttock.

Because buttock contour surgery is an elective procedure, significant medical problems that could increase the surgical risk are relative contraindications.

See the list below:

• No specific laboratory tests are necessary.

See the list below:

• No diagnostic tests specific to contour reconstruction are indicated, as long as preoperative nerve function of the lower extremities and spinal cord is documented.

The claims that a cellulite cream can reduce prominent areas generated excitement, but the claims never materialized as fact. Medical therapy has no place in contour surgery of the buttock.

Contour surgery of the buttock is achieved mainly through a surgical approach. Assessment of the deformity organizes therapies into reduction treatments, contour irregularity treatments, and augmentation treatments.

Augmentation Options

Buttock implants

A silicone gel implant is inserted under each gluteus maximus muscle through a 5- to 8-cm midline incision over the tail bone.[3] The procedure is performed either under general anesthesia or local anesthesia and sedation. The procedure usually takes about 2 hours and is mostly done as an outpatient procedure or overnight stay. The recovery is about 4-6 weeks before resuming normal activities. This is a preferred procedure for those who do not have excess fat stores or whose excess fat is not enough to allow for appropriate buttock enhancement. This procedure causes more pain than do other common cosmetic surgeries. It may take up to 6-8 months before the muscle relaxes and the implant is no longer felt.[4, 5]

Fat injection

Gentle liposuction is used to remove fatty tissue from donor sites such as the abdomen, flanks, and thighs. The removed fat is injected into the desired areas through small incisions with a fine canula. This is less invasive than implant surgery and the recovery is much faster. It allows for resuming activity in 2 days and full activity in 2 weeks. However, partial resorption of the fat may occur, and multiple sessions may be required to obtain the desired shape. The incisions are small and scarring is minimal. This technique uses the patient's own body fat; therefore, no rejection or foreign body reaction occurs. The liposuction to harvest the fat adds the additional benefit of body contouring in areas of excessive fat.

Much is written about the quality of fat harvest leading to reduced blood and fluid within the fat harvested material. However, there is a balance between centrifuging the collection to remove such fluids and potentially damaging the fat grafts. Some of the milieu around the fat cells has growth factors and nutrients that may help increase the yield of fat grafting. Patient positioning to obtain appropriate fat grafts and placement should always be considered before surgery to safely facilitate the procedure.

It has been observed that fat grafting to the buttock area can lead to fatal complications. The depth, placement, and positioning of the cannula; the volume of fat grafted; and patient selection may play a role in severe complications, such as fat emboli. There has been a significant increase in mortality throughout plastic surgery associated with fat grafting to the buttock region, and task forces have been developed to study the issue and provide guidelines that will allow potentially deadly complications to hopefully be avoided. Consent should be obtained that addresses the patient's goals along with the risks and concerns attendant with fat grafting.[6]

Although the mortality rate from the Brazilian butt lift was previously reported to be one in 3000, subsequent research indicated the rate to be one in 15,000. A study by Pazmiño and Garcia of such fatalities in south Florida, where the death rate from these fat grafts had been particularly high, indicated that such mortality most often occurred in patients who underwent surgery at high-volume budget clinics and who apparently experienced short operative times (typically about 90 minutes).[7, 8]

Rearrangement of local tissue during body contouring procedure

Using local subcutaneous flaps during a lower body lift can be a valid option for buttock augmentation in patients after massive weight loss.[9, 10] For patients with underprojected buttocks and some degree of ptosis, implants or fat injection alone may not be sufficient for restoring the contour. Autologous dermal flaps allow a buttock lift along with augmentation.

Reduction Treatments

Reduction treatments are the most common. They include suction lipectomy through conventional means, suction lipectomy with ultrasound assistance, and superficial liposculpture.

Suction lipectomy with tumescent anesthesia is the most common method of contour buttock improvement. A small, 2-4 mm cannula is commonly used, with the incision hidden in the buttock crease or the upper-outer buttock area. The buttock can be sculpted nicely with this modality.

Ultrasonic-assisted liposuction may be used when a large volume of lipodystrophy is found in the buttock. The ultrasonic machine assists with liquifying the fat and facilitates removal by conventional techniques. In the past, a somewhat larger incision was often required; however, because cooling is now integrated within the cannula and skin protectors are no longer required, this is no longer an issue. The tissues should be cooled, and skin care precautions should be used.

Superficial liposuction is another method of reshaping the buttock. The cannula is 2 mm and may be a different configuration of open ports to ensure a smoother result. This method can alter a square buttock into a desirable round shape. It may be combined with other methods to produce the overall result the patient seeks. Indeed, that lateral buttock area may be reshaped into a more athletic form by liposuction of the "sensuous triangle" described by Schlesinger.[11, 12]

A study by Avendano-Valenzuela et al indicated that improved aesthetic contouring of the gluteal region is achieved by tailoring techniques for liposuction and lipoinjection according to individual anatomical zones.[13] The reduced need for more aggressive surgical procedures decreases the risk of complications, recovery time and postoperative scarring.

Contour irregularities may be treated by the above methods, by scar revisions, and by augmentation of contour depressions using fat grafting or other autologous materials.

Studies have shown cosmetic improvement with a combination of selective liposuction and lipoinjection.[14]

Approach patient expectations with a reasonable preoperative plan. Mark the patient, highlighting contour irregularities and areas to be treated; discuss scar placement with the patient. Confirm operative positioning to ensure proper technique and exposure. Be aware of intravenous fluid intake, and prepare the tumescence fluid to prevent Xylocaine or epinephrine toxicity or overdoses. Discuss fluid requirements in advance.

Position the patient to best expose the area for surgery. This may involve a prone position, which requires appropriate padding and support for the hips and chest areas. A lateral position also may be used; give the same considerations to the axillae and legs. Many surgeons prepare their patients while the patients are awake and standing and then permit them to lie, already prepared, on a sterile operating table; this allows movements and different positioning. Be aware that some patients find this method uncomfortable and demeaning.

Once the patient is sterilized, prepared, and draped, make incisions on the preoperative marks and use a tumescence infusion for liposuction correction. Use caution to infuse marked areas and avoid nerves and deeper structures. For lipoplasty treatments, use different cannulas to achieve the optimal result for the patient and his or her specific needs. Use some type of dressing, usually a compression garment, at the completion of contour improvement.

Prepare and position patients seeking augmentation or scar revision as appropriate. Determine the pocket for augmentation preoperatively, and surgically create it with great care to avoid nerve and vascular structures and disruption of gluteal musculature. Close the incision and tape it well so the pocket remains as dissected.

Plan scar revisions similarly, with additional assistance from autologous fat injections or alloplastic materials to correct depressions. Subcuticular closures are usually used, and dressing completes the procedure.

Examine the patient postoperatively for general operative recovery and specific incision healing. Examine all areas. Advise the patient to avoid exercise and increased activity for approximately 3 weeks. Provide customary incision and operative site care.

The patient must understand that while immediate results are observed, the final results are usually achieved from 6 months to 1 year after the procedure. Massage and, occasionally, ultrasound treatment may help smooth areas of operative unevenness or swelling. Patients who have undergone liposuction should wear a compression garment until most of the swelling has subsided.

Many complications are possible, including unmet expectations, unevenness or irregularities (contour problems), anesthesia reactions, toxicity from Xylocaine or epinephrine, and remaining local areas of numbness.[15]

Unmet expectations

The patient's expectations may differ from the results unless a good informed consent process that includes realistic possibilities was used. This is included as a complication because patients often desire impossible results. This may be avoided by rejecting patients with unreasonable and persistent expectations. Fat grafting is often met with some disappointment, as some of the fat grafts do not survive, yet the patient continues to age and some of the normal volume changes over time. It should be discussed that this type of procedure may have to be repeated over time to maintain a desired appearance.

Contour problems

Contour problems are not uncommon with lipoplasty. They may be prevented somewhat by using small cannulas and a cross pattern to avoid disproportionate fat removal. In addition, keep the customary cannula away from the superficial area. Specific cannulas are available for superficial lipoplasty. Burns and hypertrophic scarring are more common with ultrasonic-assisted lipoplasty if the skin is not kept cool and protected. Infuse tumescence fluid into areas of ultrasonic usage; also, use moist towels and a skin protector or use constant infiltration of the cannula with cooling fluid through an integrated sheath.

Anesthetic and other general complications

Anesthetic and general complications can occur. They often involve fluid overload, lack of adequate replacement, and general anesthetic complications. Ensure good communication between the anesthesia team and the surgeon regarding the patient's requirements. Prone positioning is difficult for the anesthesia team.

Lidocaine toxicity occurs if excessive doses are administered via tumescence fluids. The usual adult maximum dose is 300 mg; distribute this through the combination of tumescence fluids. Typically, 4 mg/kg is the maximum level, but with combined epinephrine, this may actually approach 7 mg/kg. Much higher levels can be used safely, but guidelines are not readily available. The overall dose is important. It is also accepted that some degree of partitioning of the injected tumescence exists, and a portion is removed by suction lipectomy. As much as 35 mg/kg (tumescence) can be used.

Symptoms of lidocaine toxicity appear as CNS toxicity (eg, anxiety, apprehension, restlessness, nervousness, disorientation, confusion, dizziness, blurred vision, tremors, nausea and/or vomiting, shivering, seizures). Manifestations of drowsiness, unconsciousness, respiratory depression, and respiratory arrest are also possible. During anesthesia, maintaining blood pressure may be difficult and increased bleeding may occur.

Toxicity from epinephrine may cause symptoms. Limit the administration over the period of tumescence, and discuss patient stability with the anesthesia team.

Persistent numbness

Local areas of numbness may persist for a long time. The best plan is to discuss this possibility before the surgery. Usually, such areas eventually improve and sensation returns. During this period, it is important for the patient to gently massage and desensitize the area to prevent a neuroma or pain development. A full recovery may require 2 years or longer.

Complications specific to surgery type

With buttock implantation, complications include infection, wound dehiscence and implant exposure, reoperation, rupture of the implant, seroma, capsular contracture, asymmetry, implant shift, overcorrection, sciatic nerve injury, and paresthesia. Rates vary in different reported series.[16]

With fat injection, the most commonly reported complications are fat resorption, asymmetry, irregularity, paresthesias, seroma, abscess, and cellulitis.

A literature review by Oranges et al reported overall complication rates for gluteal augmentation techniques to be as follows: gluteal augmentation with implants (30.5%), local flaps (22%), and autologous fat grafting (10.5%).[17]

A retrospective study by Senderoff found revision buttock implantation surgery (43 patients) to have an overall complication rate of 17.8%.[18]

The outcome of buttock contour surgery depends on the deformity (see image below). Excellent results are obtained by liposculpture (routine or ultrasonic-assisted). Depressed scars and defects are more difficult to correct because of the curved buttock shape and the scar-contracting elements across the curvature. Implantation of materials to fill defects may not last but should improve the defect.

The initial outcome is an improvement but is not the final result. Liposuction usually requires at least 6 months and often 1 year before final results are achieved. Caution the patient about early expectations. Approximately 1 month after surgery, marked improvement is noticeable. The initial postoperative weight gain from fluid retention is gone, and the results are approaching a realized form.

Perform massage and compression of the area to facilitate skin shrinkage to the new form over the next few months. This massage is typically done by the patient at home or by a physical therapist or massage therapist. If some form of compression is not performed, the results will not be optimal. Final results may be noted when anesthesia of operated areas subsides, pinching of the area is possible, and the swollen feeling is gone. The prognosis of contour improvements is good if the patient follows all directions and instructions.

The outlook and prognosis of scar revisions are also good. A rule of scar and trauma revisions is that as long as something is changed with the revision, the results should be different. That is, if an aspect of the scar (eg, trauma, infection, suture technique) can be changed with the scar revision, expect some degree of improvement. Massage and the external addition of silicone sheeting or steroid cream may benefit scar revision.

The future of contour surgery continues to be positive. More superficial irregularities will be safely addressed with less surgical risk. The cannulas and instruments will continue to undergo refinement, becoming more affordable and more applicable to a wider selection of patients.

Surgical advances and patient demands will always be accompanied by gimmicks. "Magic" creams will continue to be touted to remove cellulite, along with faster and safer machines promising a "too-good-to-believe" result. Patients must be cautious about such promises. Those who make such promises should be investigated thoroughly regarding board certification in plastic surgery and their good reputation. Good results are achieved with careful planning, good patient selection, and surgical skill.

A note must be added regarding the efficacy of the "roller-suction" machines touted to help with cellulite. All large-scale studies of these massage devices, when controlled for weight gain and loss, have shown absolutely no benefit. Herbal wraps and other purportedly magic potions have a similar poor contribution to improving the contour of this area.

An objective measure of the buttock volume or projection is needed to assess the efficacy of each treatment and the long-term result.

For excellent patient education resources, see eMedicineHealth's patient education article Liposuction.