Trunk Deformity Reconstruction

Acute Reconstructive Management of the Trunk Soft Tissue Layers

In the acute setting, superficial skin loss may be treated in a relatively conservative fashion with standard dressings or with the application of dermo-protective matrices such as Biobrane or Suprathel. A recent Cochrane review aiming to assess the effects of burn wound dressings on partial-thickness burns suggested that dressing selection should be based on their effects on healing but that other parameters such as ease of application and removal, dressing change requirements, cost, and patient comfort should also be considered. Their conclusion was that, following analysis of a total of 30 randomized controlled trials (RCTs), traditional dressings containing silver sulfadiazine (SSD) were consistently associated with poorer healing outcomes than were biosynthetic (skin substitute) dressings, silver-containing dressings, and silicon-coated dressings.

Dermo-protective skin substitutes are characteristically used to aid reepithelialization in the acute management of partial-thickness burns until full healing occurs. Biobrane is a bi-layered semi-permeable biosynthetic wound dressing with an outer silicone layer, a nylon-net in the middle layer, and an inner porcine collagen type I layer. Suprathel is a synthetic wound dressing consisting of a copolymer-foil of D,L-laktidtrimethylencarbonate and e-caprolakton.

A study comparing both dressings showed satisfying comparable clinical results in the use of both types of prosthetic material.

In the acute setting, extensive burns and injudicious fluid resuscitation may lead to ACS, defined by the presence of organ dysfunction because of increased abdominal pressure or IAH.

Patients with severe burns are at risk for developing ACS due to the large volume of resuscitation fluid that is infused, abdominal wall compliance, and capillary leakage due to increased permeability. This subsequently reduces blood flow to the abdominal viscera and may lead to bowel ischemia, multiorgan failure, and death if not properly addressed.

When decompressive laparotomy is necessary, the complications due to an open abdomen add to those due to the extent of the burn.

Decompressive laparotomy may help in the survival of burn patients, but the mortality can still be up to 50% and introduce a serious physiological and reconstructive challenge.

Recently updated consensus definitions and clinical practice guidelines from the World Society of the Abdominal Compartment Syndrome state that decompressive laparotomy is the standard surgical method to treat severe IAH/ACS despite considerable potential mortality even after decompression. Taking into consideration that the longer the abdomen remains open, the greater the potential complications, this forum of experts established several recommendations significant for the reconstructive strategies of the open abdomen following decompressive laparotomy for IAH:

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  Prevent visceral adhesions, loss of soft tissue coverage, lateralization of the abdominal musculature and its fascia, malnutrition, and enteric fistulae.

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  Aim to achieve same-hospital-stay closure of the open abdomen.

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  Consider the use of negative pressure wound therapy (NPWT) for temporary abdominal closure after decompressive laparotomy.

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  Consider component separation to facilitate early fascial closure of the open abdomen.

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  Bioprosthetic meshes should not be routinely used in the early closure of the open abdomen compared to alternative strategies.

Several temporizing options using external devices have been suggested to aid the closure of the abdomen following decompressive laparotomy.

The use of techniques that apply to the closure of large hernia defects can be used to close large decompressive laparotomy defects as well. The technique of component separation is not contraindicated in the burn patient, even in large burns with a deep pattern of injury.

In this series, fascial access was obtained by raising burned skin flaps at the level of the costal margin from the anterior superior iliac spine inferiorly to the ribs superiorly. These skin flaps were then excised to facilitate grafting of the abdominal wall. The fascial release that facilitated abdominal closure was made, in standard fashion, lateral to the rectus sheath through the aponeurosis of the external oblique muscle.

The acute reconstruction of trunk soft tissue loss related to the direct effects of the burn injury follows the steps applied to other parts of the body. Following stabilization, resuscitation, and débridement, acute soft tissue cover methods are decided based on the depth and extent of the burn, the availability of suitable donor sites, and the microbiology and nutritional status of the patient.

Extensive burns may destroy the skin layers and their blood supply to the extreme of making impossible self-healing and regeneration following a conservative approach. There are occasions in which the paucity of autologous skin or concerns regarding the infection control status of the recipient site recommends the use of temporizing techniques such as xenografts or allografts ( Fig. 52.1 ) until definitive skin cover is achieved. Characteristically split-thickness autografting has been the standard method to address soft tissue loss during this period. A recent expert panel white paper on the surgical management of the burn wound and use of skin substitutes clearly establishes the differences between skin substitute—a commercial biomaterial, engineered tissue, or combination of materials and cells or tissues that can be substituted for skin autograft or allograft in a clinical procedure—from a skin replacement, which is a tissue or graft that permanently replaces lost skin with healthy skin.

Skin grafts are usually meshed to a desired level of expansion; split-thickness grafts are frequently used if the wound bed exhibits appropriate vascularity and the donor skin is available in appropriate quantities. As every burns surgeon is aware, expansion of the SSG is associated with small areas of the wound healing by secondary intention and a poorer scar outcome.

In cases of extreme paucity of donor sites, the use of micrografting (Meek) techniques with or without dermal regeneration templates may represent a suitable form of reconstruction in the acute period ( Figs. 52.2 and 52.3 ).

Tissue engineering options have expanded the possibilities of reconstruction for the burned trunk. The ideal tissue engineering device needs to be rapidly available, autologous, site-matched, possess reliable wound adherence and express minimal donor site morbidity, be clinically manageable, improve the quality of scar, and be affordable.

Some of the techniques currently available involve the use of dermal scaffolds such as Integra (Integra Life Sciences Corporation, Plainsboro, NJ), Matriderm (MedSkin Solutions, Dr. Suwelack, Germany), or Pelnac (Gunze Ltd., Japan) and the use of confluent and nonconfluent keratinocyte culture techniques such as Recell (Avita Medical, UK).

A deeper pattern of injury may require the use of more complex steps of the reconstructive ladder. The chest and abdomen, due to their anatomic proximity, are injured together frequently in flame, scald, or electrical injuries. In these situations, in which deep visceral structures may become exposed, the use of large flaps such as the omentum, latissimus dorsi, rectus abdominis, or deltopectoral may be indicated.

Late Reconstructive Management of the Trunk Soft Tissue Layers

The late reconstruction of the soft tissue layers addresses the impact of abnormal scarring on the cosmetic and functional integrity of the trunk. Reconstruction due to scars in the boundaries of the trunk that alter the functionality of the neck, axillae, and groin area and reconstruction of specific body parts such as the breast will be addressed later in the chapter.

The reconstruction of the soft tissue layers of the trunk is simultaneous with recognized protocols of scar management such as massaging, moisturizing, and sun-protecting the scar; application of compression garments; and physical therapy. These are beyond the scope of this chapter and will not be addressed here.

The wise use of recognized surgical techniques in the acute phase of scar maturation diminishes the complexity of reconstructive needs. These include the use of darts in escharotomies when crossing joints, placing the seams of the skin grafts following skin tension lines, using sheet grafts when possible, placing grafts transversely over joints, applying early pressure therapy, and implementing an early ambulation and exercise regimen.

The skin layers of the trunk may be affected by abnormal pigmentation, hypervascularity, hypertrophic and keloid scars, texture abnormalities in both the reconstructed and the donor site ( Figs. 52.4 to 52.6 ), by the presence of contractures that can be well defined or diffuse, and by the presence of unstable tissue ( Figs. 52.7 and 52.8 ) with a tendency to breaking down. The approach to the management of these abnormalities is to always prioritize function over cosmesis, have a realistic approach to reconstruction, and appropriately time any surgical procedure to avoid interfering with the maturation of scars.

Selective scar resection and direct closure of the subsequent defect may be used in the trunk providing that sufficient skin laxity and tension-free closure exists.

The skin of the abdomen, with its natural laxity and the possibility of redundant tissue, allows the use of recognized techniques of reconstruction such as abdominoplasty and liposuction to become valid options of soft tissue cover after scar excision.

The use of full-thickness grafts or dermal regeneration templates constitutes the next stage in the resurfacing and reconstruction of elective scar revision surgery. They provide the patient with a reconstruction of improved pliability that has been proved to withstand even the natural skin tension resulting from a pregnancy.

In cases of cosmetically disfiguring scars that exhibit lack of pliability, the use of tissue expansion techniques either on their own or combined with flap techniques in the trunk offers the possibility of providing reconstruction with autologous skin following a two-stage procedure. The first stage introduces the expanders in a pocket near the scar. Once appropriate expansion has been achieved, including overexpansion, the scar is excised and the subsequent defect covered with a flap of expanded skin usually using a technique of advancement, transposition, or rotation. It has been postulated that the insertion of the largest possible expander, a rectangular shape, and the method of advancement provides the largest amount of expanded tissue available. Traditional tissue expanders are connected to a tubing system and a port that is placed usually over a bony prominence distant to the implant itself. Recently the use of osmotic tissue expanders has introduced a new option for reconstruction and resurfacing of defects after scar excision by avoiding the need for repeated injections. This is especially useful when dealing with pediatric patients.

The insertion of osmotic tissue expanders requires careful dissection of an appropriately sized pocket to place the prosthesis. This is an important issue in the learning curve of the early user of this technique because the osmotic tissue expander tends to grow relatively quickly during the first 2 weeks of insertion.

Insertion of the expander too close to the scar to be reconstructed will increase the potential for implant extrusion. A sequence for the insertion of osmotic tissue expanders can be seen in Figs. 52.9 to 52.14 . Following insertion, our protocol is to review the patient weekly for the first month post insertion to review the wound and assess for breakdown or dehiscence. We then follow the patient monthly until the second stage of reconstruction. This stage includes expander removal, scar excision, and reconstruction of the defect usually by advancement ( Figs. 52.15 to 52.18 ).