Introduction

Body contouring’s deeply rooted history involves the evolution of specialized surgical techniques to sculpt and reshape the human physique. The concepts of panniculectomy and dermolipectomy were defined at the tail end of the 19th century as pioneers of this craft began to remove pendulous adipocutaneous tissue, resulting in improved functionality.¹ In the early 20th century, contour surgery began its transformation from a purely functional modality to an esthetic procedure. As such, Thorek described the first umbilicus preserving abdominoplasty in 1924.² The 1960s and 1970s saw major advances in this field as techniques involving aponeurotic plication,³ refinement in scar placement^3–6 and tissue anchoring utilizing the anatomy of the superficial fascial system⁷ were made popular. At the turn of the 21st century, the explosive growth and widespread acceptance of bariatric surgery created a new group of patients, collectively referred to as “massive weight loss patients.” New procedures were necessary to excise the redundant tissue in all areas of the body while achieving an esthetic result. The range of contour deformities seen in these patients experienced a dramatic expansion from “anterior only” to “circumferential,” establishing the circumferential dermatolipectomy as a mainstream operation in plastic surgery today.

Body contour deformities of the lower trunk exist on a spectrum from “anterior only” to “circumferential” deformities. If the lower truncal deformity is limited to moderate lipodystrophy deposits, then liposuction may be the only treatment modality required. Abdominoplasty techniques are useful if anterior skin laxity and/or abdominal wall weakness are encountered. If lateral and posterior lipodystrophy accompany the anterior deformities, then liposuction may be added to abdominoplasty in order to achieve the best possible contour. If circumferential skin and subcutaneous laxity is additionally present, then belt lipectomy procedures are usually required to adequately address the deformities.

Belt lipectomy procedures treat deformities of the lower trunk, from the ribcage to the pelvic rim, and improve the contour of the lower back and the anterior, medial and lateral thighs. It does not, however, address upper back rolls/lateral back rolls, breast, or arm contour. The belt lipectomy procedure, therefore, will not address the upper trunk, which anatomically originates at the inferior border of the neck and extends to include the inframammary fold. To correct deformities of this anatomic unit, the authors suggest using an “upper body lift” procedure.

Relevant Anatomy

It is critical to understand the anatomy, in particular the blood supply, of the abdomen and all its variations when considering a circumferential dermatolipectomy of the lower trunk. This chapter will stop short of a detailed description of the vascular supply as this is covered elsewhere in this textbook. Preservation of the vascular supply as well as the peripheral innervation to the abdomen is a critical consideration in thwarting major complications of these procedures. The superficial fascial system, called Scarpa’s fascia in the abdomen, is a connective tissue network that exists between the subdermal plane and the deep fascia and it separates subcutaneous fat into superficial and deep layers. In thin patients, the two layers are of relatively similar thickness. Both layers demonstrate vertical or oblique fibrous septae; however, the vertically oriented compartments of the superficial layer thicken with increasing body weight and grow proportionally with the body mass index (BMI). Therefore, the superficial layer is often thicker with respect to the deep layer in patients with increased BMI. In well-defined areas of the trunk the superficial fascial system is tightly tethered to the underlying musculoskeletal surface, resulting in restriction of either descent or elevation, which typically occurs with age, fluctuations in weight, or surgical manipulation. These areas are referred to as “zones of adherence,” which behave like “hooks” that grasp the fat/skin envelope as it succumbs to gravitational forces, most noticeably following skin deflation from massive weight loss. It is important to know the anatomy of these zones and how they influence tissue draping. The zones of adherence are located in the inframammary, inguinal, suprapubic, and gluteal regions. The zones of adherence overlying the spine and sternum as well as the area located between the hip and lateral thigh fat deposits are strong and consistently present. On the other hand, the zone of adherence overlying the midline linea alba of the abdomen is relatively weak and occasionally nonexistent. Another strong zone of adherence is in the inguinal region, which plays an integral role in the final scar position following a belt lipectomy. A weaker zone of adherence exists in the horizontal suprapubic area, creating a suprapubic crease, which varies between individuals. Along with the inguinal zones of adherence, the suprapubic zone is responsible for the panniculus overhanging the mons pubis. The zone of adherence between the hip and the lateral thigh fat deposits mentioned above is an important anatomic structure because it prevents superior and inferior movement of lateral thigh tissue, especially during surgical manipulation. Destruction of this zone is often necessary if substantial elevation and redraping of the lateral thigh soft tissue envelope is desired, such as with the lower body lift type II as described by Lockwood.

Disease Process

In general, there are three groups of patients for which a belt lipectomy is beneficial.⁸ The majority are massive weight loss patients,⁸ who are not a homogeneous group. Although the pathophysiologic processes are similar and the indications and principles in operative design are comparable, their individual BMI at presentation, fat deposition pattern, and quality of their skin–fat envelope can result in a wide divergence in the nature of their physical deformity. Massive weight loss patients must therefore be well informed regarding the expected body contour outcome to avoid disappointment. Bariatric surgeons tend to emphasize overall weight reduction and often neglect to inform patients that many of the changes in their body habitus are not reversible with weight loss and that normalcy from an esthetic standpoint is often unattainable. The redundant skin with irreversible laxity is almost always circumferential in these patients, resulting in a truncal pattern of an inverted cone.

The second group of patients that may benefit from body lift/belt lipectomy are the 9–13 kg (20–30 pounds) overweight patients (BMI of 26–28). These patients have never lost significant weight despite reasonable exercise and nutritional support, which very often results in circumferential lipodystrophy and an overall lack of definition of the lower trunk. A third group is comprised of normal weight patients who desire more dramatic improvements in lower truncal contour than a conventional abdominoplasty can achieve. These normal BMI patients often seek drastic improvement in the contour of their anterior and lateral thighs, buttocks and lower back. Some of these patients can be treated with an abdominoplasty combined with liposuction of specific areas; however, if significant lifting and contour manipulation is required, a circumferential excisional procedure becomes necessary. A subset of this group is made up of older patients whose skin laxity requires the pull created by the circumferential excision. Liposuction alone will not sufficiently address the deformity as irreversible skin laxity precludes the contraction necessary to achieve the desired contour.

Diagnosis and Presentation

The discussions to follow will focus on the massive weight loss patient, with occasional reference to the other groups when appropriate. As discussed previously, massive weight loss patients vary in their BMI level, fat deposition pattern and quality of skin–fat envelope, which influences their presentation. Even though massive weight loss patients, through lifestyle changes or bariatric surgery, will tend to eventually attain a stable BMI, they will still present to the plastic surgeon at different levels. It is important for the plastic surgeon to elucidate a timeline of weight stabilization, as some patients will have a false plateau after which they will resume weight loss. Therefore, it is wise to consult with the bariatric surgeon before considering body-contouring procedures. If the patient loses weight through bariatric surgery, the type of procedure chosen for the patient will likely affect their final BMI. Lap-Band® procedures tend to induce the least amount of weight loss, followed by gastric sleeve resection and gastric bypass, while duodenal switch patients tend to have the most dramatic fall in BMI.

The unique fat deposition pattern also plays an important role in determining the specific contour deformity in massive weight loss patients. A patient’s fat deposition as well as fat loss pattern is genetically regulated and is therefore quite individualistic. For example, men tend to deposit fat intraperitoneally and in the flank region (“love handles”), presenting with mostly central, or “apple shaped,” obesity. Women, on the other hand, tend to store fat in a “pear shaped pattern” in the extraperitoneal space, the lower abdomen, hips, and thighs. These patterns are just two of many potential fat deposition presentations. Weight loss varies similarly, with some patients losing fat in equal proportions throughout their body while others experience more of an asymmetric pattern with relatively more or less lost in different areas. While fat deposition undoubtedly plays a major role in determining overall body contour, it is important to recognize that the underlying musculoskeletal foundation also contributes to the overall appearance of the individual and therefore must be considered when establishing expectations of the final cosmetic result.

The characteristic of the skin–fat envelope is a third factor that affects the presentation of massive weight loss patients. The envelope is of major interest to the plastic surgeon and its intrinsic qualities are critical as it influences overall cosmetic outcome. The thickness of the post-weight loss subcutaneous fat tissue is important, as thin layers generally allow for greater pliability and movement of overlying skin, which is important in predicting the final cosmetic result. The authors introduced the concept of “translation of pull” as an excellent predictor of the final results. Prior to surgery, the lateral abdominal tissues are pinched in order to simulate the effect of the lateral abdominal resection on the distal thigh contour (see Fig. 32.1). Thicker nonpliable skin–fat envelopes, which are typical of patients with higher presenting BMIs, have little translation of pull in these areas, indicating that the potential overall improvement in body contour is limited. As a general guideline, the greater the drop in BMI for an individual patient, the greater the “translation of pull.”

FIG. 32.1 The “translation of pull” is shown by the red arrow, which demonstrates the extent of improvement away from the area of resection (simulated by the pinching of tissues).

Nearly all massive weight loss patients present with a “hanging panniculus,” the size and shape of which varies with the patient’s intrinsic fat deposition pattern. Additionally, almost every massive weight loss patient will present with “ptotic mons pubis,” most commonly exhibiting vertical excess and varying degrees of horizontal excess. The hanging skin/fat envelope often blunts the waistline as it drapes from the ribs to below the pelvic brim. Despite weight loss, there are often residual fat deposits in the hip and lower back region that add to this blunting. The anterior and lateral thighs are greatly affected by the weight gain/weight loss process and are therefore typically ptotic. The effect on the thighs is less dramatic in the “20–30 pound overweight group” and the “normal weight group,” but nevertheless it remains an area of concern for these patients.

Similar to the thighs, the buttock in the massive weight loss patient is usually ptotic as a result of the weight loss process. The projection of the buttocks is generally correlated with the patient’s BMI, with patients above a BMI of 35 presenting with overly projected buttocks and patients with BMI under 26 with flat appearing and underprojected shape. Many massive weight loss patients also display poor demarcation between the lower back and buttocks.

Back rolls can be located in the lower, mid or upper back and are particularly displeasing to many patients. High back rolls, which are usually contiguous with breast rolls, are not affected by the belt lipectomy and require an upper body lift. Low back rolls are generally improved with the belt lipectomy. Few patients present with mid back, or “no man’s land,” rolls, which are difficult to treat with either an upper body lift or a belt lipectomy.

The psychiatric presentation of the patient requires special consideration. Although the plastic surgeon may be successful in reshaping the patient’s abnormal contour, psychological issues may persist. An obesity-associated depression may persist as well as estrangement from family and friends who might feel as if they have lost a fellow “sufferer.”

Preoperative Preparation