Single-stage Matriderm® and skin grafting as an alternative reconstruction in high-voltage injuries

Artificial Dermis and Human Recombinant Epidermal Growth Factor Application for the Management of Critical Size Calvarial Defect

Restoration of the 3-dimensional structure of the facial and calvarial skeleton after trauma or ablative oncologic surgeries serves as a framework for soft tissue reconstruction. In the present study, the authors aimed to evaluate the osteogenic effect of artificial dermis and epidermal growth factor treatment in critical-sized calvarial defects, which cannot be healed spontaneously. 8 mm calvarial defects were created in 28 male rats and filled with the artificial dermis, the artificial dermis and growth factor, growth factor or left untreated. Atomic absorption spectrometry was used to determine the amount of calcium, scanning electron microscopy was used to show the bone tissue in 3 dimensions, and immunohistochemistry was used to assess the bone formation and cell density. Histologic evaluation at 6 weeks showed incomplete bone regeneration in all groups. No statistical differences were found between the groups with regard to their scores for the following: inflammation, new bone formation, osteocyte density, resorption of bone at the edges of the defect, or fibrous tissue formation in the defect area. In conclusion, the predictability of bone formation in critical-size defects is not clear. Contrary to popular belief, the combined use of epidermal growth factor with artificial dermis or alone did not enhance the potential for osseous healing.

Use of a collagen-elastin matrix with split-thickness skin graft for defect coverage in complex wounds

OBJECTIVE

Severe soft tissue damage with destruction of the dermis requires plastic reconstructive treatment. For multimorbid patients or patients unable to undergo major reconstructive surgery, use of dermal substitutes, such as a collagen-elastin matrix (CEM) with a split-thickness skin graft (STSG), instead of local or free flap surgery, may be a valid and easy treatment option. We aimed to investigate and compare the outcomes and rate of successful defect reconstruction using CEM plus STSG, using either a one-step approach (simultaneous CEM and STSG) or a two-step approach (CEM and negative wound pressure therapy (NPWT), with secondary STSG transplantation).

METHOD

A single-centre, retrospective follow-up study of patients who had received CEM was conducted. Wounds had been treated with an STSG transplantation covering a CEM (MatriDerm, MedSkin Solutions Dr. Suwelack AG, Germany). Previous attempts at wound closure with conventional methods had failed in the selected patient population, which would usually have resulted in flap surgery.

RESULTS

Overall, 46 patients were included (mean age 60.9±20.0 years), with a total of 49 wound sites. We analysed 38 patients with wounds that did not require flap coverage; 18 patients received the one-step approach and 20 patients received the two-step approach. The mean follow-up in these patients was 22±11.5 months, and one patient was lost to follow-up. Overall, 29 (78.4%) wounds remained closed. Wounds which did not successfully heal were related to comorbidities, such as diabetes, alcohol misuse and smoking. Using the one-step approach, long-term defect coverage was achieved in 13 (76.5%) wounds and 16 (80.0%) wounds were closed using the two-step approach. However, there was no statistically significant differences between the one- or two-step approaches regarding the rate of development of a wound healing disorder.

CONCLUSION

Wound closure was achieved in 38 complex wounds using CEM plus STSG, while 11 wounds needed secondary flap coverage. In the flap-free wounds, there were no statistically significant differences between the one-step versus two-step approach. Using a simple defect reconstruction algorithm, we successfully used CEM plus STSG to treat complex wounds.

Utilization of Perifascial Loose Areolar Tissue Grafting as an Autologous Dermal Substitute in Extremity Burns

BACKGROUND

Perifascial areolar tissue (PAT) is an areolar layer over the muscle fascia. PAT has been shown to be resistant to ischemia and prone to survival even in ischemic conditions. PAT grafts provide a vascular tissue layer on necrotic bone and tendons where skin grafting is not possible. The effect of PAT grafting on burn reconstruction has not yet been reported. Thus, in this study, we aimed to present our experience and discuss the role of PAT grafting in extremity burn reconstruction.

METHODS

Between January 2019 and December 2020, 16 PAT grafting procedures were performed in 11 patients. All patients had second- or third-degree burns in the upper and lower extremities, with exposed bone or tendon. PAT grafts were harvested from the abdominal region and were used for the upper extremity in 7 patients and the lower extremity in 4 patients. Immediate skin grafting was performed during the same session.

RESULTS

The patients' mean age was 50.7 years; defect size, 3.3 × 3 cm²; and follow-up time, 11.8 months. The survival rates of the PAT and skin grafts were 93.8% and 68.6%, respectively. Partial skin graft losses were encountered in 4 patients, and total skin graft loss was seen in 1 patient.

CONCLUSION

PAT grafting is an alternative method to the use of dermal substitutes and flap surgery in small-to-medium-sized defects with exposed bone and tendon in burn patients.

Efficacy and Complications Associated with Acellular Dermal Substitute Use in the Treatment of Acute Burns: A Systematic Review and Meta-Analysis

Over several decades, skin substitutes have become an essential tool in acute burn surgery, particularly in major burns, where scarce donor tissues can limit the availability of autografts. This systematic review aimed to assess the efficacy, complication rates, and long-term outcomes of acellular dermal substitutes in acute burns and compare these to conventional skin grafting methods of coverage. A search of PubMed, Web of Science, and CENTRAL for appropriate randomized controlled trials (RCTs), non-randomized trials, and observational studies was conducted. Following screening, nine RCTs and seven observational studies fulfilled our inclusion and exclusion criteria. Our primary outcomes, which were graft take and incidence of infection, found no significant difference between the substitute and control procedures in a meta-analysis (p = 0.37 and p = 0.87, respectively). For our secondary outcomes, the studies were analyzed via narrative synthesis, which reported variable rates of graft loss and duration of acute hospital stay, from which definitive conclusions could not be drawn due to the heterogeneity in reporting. Despite a high risk of bias in the included studies, the evidence reviewed suggests that the treatment of an acute burn with a substitute may improve scar quality when compared to conventional grafting. This review therefore suggests that acellular dermal substitutes offer a viable method for staging the closure of deep partial- and full-thickness acute burns, although more robust RCTs with less heterogeneity are needed to support these conclusions.

Dermal Regenerative Templates in Orthopaedic Surgery

Management of soft-tissue injuries is a critical principle in the treatment of orthopaedic trauma. Understanding the options for soft-tissue reconstruction is vital for successful patient outcomes. Application of dermal regenerative templates (DRTs) in traumatic wounds has created a new rung in the reconstructive ladder bridging the gap between skin graft and flap coverage. There are multiple DRT products with specific clinical indications and mechanisms of action. This review outlines the up-to-date specifications and uses of DRT in commonly seen orthopaedic injuries.

Long-term results of split-thickness skin grafting with and without additional dermal matrix in severe traumatic soft tissue defects of the lower limb

PURPOSE

Aim of this study was to compare the use of split-thickness skin graft (STSG) with and without additional MatriDerm^® application in a predominantly one-step procedure for the treatment of severe traumatic soft tissue defects of the lower limb.

METHODS

This retrospective study included patients treated in a European level I trauma center between June 2013 and July 2018 in terms of a severe traumatic soft tissue defect of the lower extremity using STSG alone or in combination with the acellular dermal substitute MatriDerm^®. The healing of the soft tissue defect was measured by assessment of the take rate. Outcome quality of the scar tissue was assessed using the Vancouver Scar Scale.

RESULTS

A total of 147 cases were included in this study. The overall healing rate (number of patients with take rate ≥ 75%) was 88/147 (60%) and did not demonstrate significant differences between the treatment groups (p = 0.15). Despite the difference in wound complexity between the treatment groups, there was no difference regarding the scar tissue quality 12 months postoperatively. In about 25% of all cases, a post-operative event was mentioned that had to be revised surgically.

CONCLUSION

Surgical treatment with STSG and additional MatriDerm^® application can be recommended as satisfactory alternative for dermis replacement in patients with severe skin defects, independent of age. The additional MatriDerm^® use allows for bridging of exposed ligaments, tendons, vessels or bones without relevant differences in cosmetical outcome.

Use of Dermal Regenerative Templates for Burns

Autologous skin grafting has permitted survival and restoration of function in burn injuries of ever larger total body surface area (TBSA) sizes. However, the goal of replacing "like with like" skin structures is often impossible because full-thickness donor harvesting requires primary closure at the donor site for it to heal. Split-thickness skin grafting (STSG), on the other hand, only harvests part of the dermis at the donor site, allowing it to re-epithelialize on its own. The development of the first dermal regenerative template (DRT) in the late 1970s represented a major advance in tissue engineering that addresses the issue of insufficient dermal replacement when STSGs are applied to the full-thickness defect. This review aims to provide an overview of currently available DRTs in burn management from a clinician's perspective. It focuses on the main strengths and pitfalls of each product and provides clinical pearls based on clinical experience and evidence.

Long-term experience with a collagen-elastin scaffold in combination with split-thickness skin grafts for the treatment of full-thickness soft tissue defects: improvements in outcome-a retrospective cohort study and case report

Purpose

The management of severe soft tissue injuries to the extremities with full-thickness wounds poses a challenge to the patient and surgeon. Dermal substitutes are used increasingly in these defects. The aim of this study was to investigate the impact of the type of injury on the success rate of Matriderm® (MD)-augmented split-thickness skin grafting, as well as the role of negative pressure wound therapy (NPWT) in preconditioning of the wounds, with a special focus on the reduction of the bioburden.

Methods

In this study, 45 wounds (44 affecting lower extremities (97.7%)), resulting from different types of injuries: soft tissue (ST), soft tissue complications from closed fracture (F), and open fracture (OF) in 43 patients (age 55.0 ± 18.2 years, 46.7% female), were treated with the simultaneous application of MD and split-thickness skin grafting. The study was designed as a retrospective cohort study from March 2013 to March 2020. Patients were stratified into three groups: ST, F, and OF. Outcome variables were defined as the recurrence of treated wound defects, which required revision surgery, and the reduction of bioburden in terms of reduction of number of different bacterial strains. For statistical analysis, Student’s t-test, analysis of variance (ANOVA), Mann–Whitney U test, and Pearson’s chi-squared test were used.

Results

There was no significant difference in the rate of recurrence in the different groups (F: 0%; OF: 11.1%; ST: 9.5%). The duration of VAC therapy significantly differed between the groups (F: 10.8 days; OF: 22.7 days; ST: 12.6 days (p < 0.05)). A clinically significant reduction of bioburden was achieved with NPWT (bacterial shift (mean (SD), F: − 2.25 (1.89); OF: − 1.9 (1.37); ST: − 2.6 (2.2)).

Conclusion

MD-augmented split-thickness skin grafting is an appropriate treatment option for full-thickness wounds with take rates of about 90%. The complexity of an injury significantly impacts the duration of the soft tissue treatment but does not have an influence on the take rate. NPWT leads to a relevant reduction of bioburden and is therefore an important part in the preconditioning of full-thickness wounds.

Implementation and Validation of Free Flaps in Acute and Reconstructive Burn Care

Microsurgical free flap reconstruction in acute burn care offers the option of reconstructing even challenging defects in a single stage procedure. Due to altered rheological and hemodynamic conditions in severely burned patients, it bears the risk of a higher complication rate compared to microsurgical reconstruction in other patients. To avoid failure, appropriate indications for free flap reconstruction should be reviewed thoroughly. Several aspects concerning timing of the procedure, individual flap choice, selection and preparation of the recipient vessels, and perioperative measures must be considered. Respecting these specific conditions, a low complication rate, comparable to those seen in microsurgical reconstruction of other traumatic limb defects, can be observed. Hence, the free flap procedure in acute burn care is a relatively safe and reliable tool in the armamentarium of acute burn surgery. In reconstructive burn care, microsurgical tissue transfer is routinely used to treat scar contractures. Due to the more robust perioperative condition of patients, even lower rates of complication are seen in microsurgical reconstruction.

Role, Management, and Outcome of Free Flap Reconstruction for Acute Full-Thickness Burns in Hands

INTRODUCTION

Severe thermal trauma to the hand can result in major impairment and reduced function due to defective healing or even extremity loss. Full-thickness injuries frequently incur exposure of tendons or bone and require an early and stable coverage with soft tissue transplants to allow for rapid induction of exercise and to preserve structures and hand function. Free tissue transfer to the hand after thermal trauma is a rare indication, and safety, management, and outcome of free flap surgery for severe acute burn injuries to the hand remains underreported.

METHODS

Patients with primary reconstructions of full-thickness burn injuries to the hand undergoing microsurgical free tissue transfer surgery were retrospectively assessed in a period from 2013 to 2016. Salvage strategy of the extremity, postoperative complications, length of hospital stay, and primary reconstructive result were quantified and analyzed. Functional outcome measures (range of motion and grip strength) were assessed during clinical follow-up examinations.

RESULTS

During the investigated period, 13 patients were identified undergoing reconstruction of 14 hands via free flap transplantation after severe burn injury in the acute phase. Nine anteriolateral thigh flaps (64%), 3 latissimus dorsi flaps (18%), 1 serratus anterior flap, and 1 tensor fasciae lata flap (7%) were performed. In all cases, salvage of the affected extremity was achieved, although 1 flap (7%) was lost during the early postoperative period requiring secondary reconstruction via pedicled groin flap. Further complications were venous thrombosis (n = 2; 14%) and hematoma (n = 2; 14%). Mean length of hospital stay was 51 days. Functional outcome during follow-up examination after an average of 9.3 months was inhomogeneous depending on the pattern of injury and ranged from complete recovery to nearly entire loss of hand function.

CONCLUSIONS

Free flap transfer can be a mandatory and valuable tool to cover full-thickness burn injuries of the hand early in the clinical course of thermal trauma and may provide extremity salvage by favorable means of reconstruction to achieve acceptable functional outcomes, in the most severe cases. Although microsurgical failure rates in burn patients are slightly higher than in free flap transfer to the upper extremity in general, it can be performed with reasonable risk-to-benefit ratio.

Tissue Engineering of Axially Vascularized Soft-Tissue Flaps with a Poly-(ɛ-Caprolactone) Nanofiber-Hydrogel Composite

Objective: To develop a novel approach for tissue engineering of soft-tissue flaps suitable for free microsurgical transfer, using an injectable nanofiber hydrogel composite (NHC) vascularized by an arteriovenous (AV) loop. Approach: A rat AV loop model was used for tissue engineering of vascularized soft-tissue flaps. NHC or collagen-elastin (CE) scaffolds were implanted into isolation chambers together with an AV loop and explanted after 15 days. Saphenous veins were implanted into the scaffolds as controls. Neoangiogenesis, ultrastructure, and protein expression of SYNJ2BP, EPHA2, and FOXC1 were analyzed by immunohistochemistry and compared between the groups. Rheological properties were compared between the two scaffolds and native human adipose tissue. Results: A functional neovascularization was evident in NHC flaps with its amount being comparable with CE flaps. Scanning electron microscopy revealed a strong mononuclear cell infiltration along the nanofibers in NHC flaps and a trend toward higher fiber alignment compared with CE flaps. SYNJ2BP and EPHA2 expression in endothelial cells (ECs) was lower in NHC flaps compared with CE flaps, whereas FOXC1 expression was increased in NHC flaps. Compared with the stiffer CE flaps, the NHC flaps showed similar rheological properties to native human adipose tissue. Innovation: This is the first study to demonstrate the feasibility of tissue engineering of soft-tissue flaps with similar rheological properties as human fat, suitable for microsurgical transfer using an injectable nanofiber hydrogel composite. Conclusions: The injectable NHC scaffold is suitable for tissue engineering of axially vascularized soft-tissue flaps with a solid neovascularization, strong cellular infiltration, and biomechanical properties similar to human fat. Our data indicate that SYNJ2BP, EPHA2, and FOXC1 are involved in AV loop-associated angiogenesis and that the scaffold material has an impact on protein expression in ECs.

Benefits of cryopreserved human amniotic membranes in association with conventional treatments in the management of full-thickness burns

The use of split-thickness skin autografts (STSA) with dermal substitutes is the gold standard treatment for third-degree burn patients. In this article, we tested whether cryopreserved amniotic membranes could be beneficial to the current treatments for full-thickness burns. Swines were subjected to standardised full-thickness burn injuries, and then were randomly assigned to treatments: (a) STSA alone; (b) STSA associated with the dermal substitute, Matriderm; (c) STSA plus human amniotic membrane (HAM); and (d) STSA associated with Matriderm plus HAM. Clinical and histological assessments were performed over time. We also reported the clinical use of HAM in one patient. The addition of HAM to classic treatments reduced scar contraction. In the presence of HAM, skin wound healing displayed high elasticity and histological examination showed a dense network of long elastic fibres. The presence of HAM increased dermal neovascularization, but no effect was observed on the recruitment of inflammatory cells to the wound. Moreover, the use of HAM with classical treatments in one human patient revealed a clear benefit in terms of elasticity. These results give initial evidence to consider the clinical application of HAM to avoid post-burn contractures and therefore facilitate functional recovery after deep burn injury.

Improved Dermal Regeneration Using a Combination of Dermal Substitutes and Dermal Fibroblast Optimization: A Hypothesis

In human adults, the repair of cutaneous wounds usually leads to scar formation rather than regeneration. Dermal substitutes have been used as a regenerative template for reducing scar formation and improving the extent of dermal regeneration. However, achievement of complete regeneration is still a long way off. Dermal substitutes are characterized by unusual regenerative activity, appearing to function by acting as temporary configurational guides for cell infiltration and synthesis of new stroma. Fibroblasts are important cells with many vital functions in wound-healing processes. They are heterogeneous with distinct characteristics according to their source location, such as subcutaneous tissue, superficial-layer dermis, and deep-layer dermis. Many studies have shown that superficial dermal fibroblasts possess the potential to form dermis-like tissue. Fibroblasts in deep-layer dermis and subcutaneous tissue may play a critical role in the formation of hypertrophic scars. Fibroblast phenotype affects the newly formed dermal architecture and influences the dermal regeneration effect induced by dermal substitutes. It is hypothesized that better regeneration of the dermis can be achieved using dermal substitutes along with dermal fibroblast optimization.

Treatment of third-degree burn wounds in animal specimens: acellular dermis or partial-thickness skin graft

Several dermal products have been introduced to substitute dermal tissues. In this study we review the effects of these products on repairing third-degree burn wounds and managing complications in animal specimens. Using an interventional approach, rats were randomly assigned to four groups (G1 to G4). Two wounds were created on the back of each rat. An open wound was left on the back of rats in G1; in G2, wounds were covered with a thick rat derived-ADM product and overlying thin skin graft; on G3 rats, similar third degree ulcers were made with one ulcer covered with harvested thin skin graft. In G4, ulcers were covered with a thin rat derived-ADM product and thin graft. Factors such as take rate, histopathological score, wound contracture and graft contracture were compared on the 7th, 15th, 21st and 30th day. Mean graft take rate on the 30th day in the thick ADM, thin ADM and graft group showed a significant difference (p=0.015). Histopathological score on the 30th day in the thin ADM, thick ADM and graft group showed no considerable difference. Mean graft take rate was significantly better in the thin ADM and graft group than in the thick ADM group. Wound contracture was significantly more severe in the thick ADM and control group than in the thin ADM and graft group.

About ATMPs, SOPs and GMP: The Hurdles to Produce Novel Skin Grafts for Clinical Use

BACKGROUND

The treatment of severe full-thickness skin defects represents a significant and common clinical problem worldwide. A bio-engineered autologous skin substitute would significantly reduce the problems observed with today's gold standard.

METHODS

Within 15 years of research, the Tissue Biology Research Unit of the University Children's Hospital Zurich has developed autologous tissue-engineered skin grafts based on collagen type I hydrogels. Those products are considered as advanced therapy medicinal products (ATMPs) and are routinely produced for clinical trials in a clean room facility following the guidelines for good manufacturing practice (GMP). This article focuses on hurdles observed for the translation of ATMPs from research into the GMP environment and clinical application.

RESULTS AND CONCLUSION

Personalized medicine in the field of rare diseases has great potential. However, ATMPs are mainly developed and promoted by academia, hospitals, and small companies, which face many obstacles such as high financial burdens.

Retrospektive Analyse von56 Weichteildefekten nach einzeitiger Rekonstruktion unter Verwendung von Dermisersatzpräparaten

HINTERGRUND

Der Verschluss von Wunden mit ausgeprägtem Weichteilschaden stellt eine chirurgische Herausforderung dar und erfordert häufig umfangreiche plastische Operationen sowie freie Lappenplastiken. Die Kombination von Dermisersatzpräparaten und Spalthauttransplantationen ist eine innovative Methode die zur Versorgung von komplexen Verletzungen der Extremitäten angewandt werden kann. Wir haben diese Technik in das Standard-Handwerkszeug bei komplexen Verletzungen der Extremitäten aufgenommen. Die klinischen Ergebnisse von 56 behandelten Patienten werden vorgestellt.

PATIENTEN UND METHODEN

In 44 Fällen (78,6 %) wurde die beschriebene Methode an Defekten der unteren Extremitäten verwendet, einschließlich sieben Personen (12,5 %), die sich einer Stumpfdeckung nach Amputation unterzogen. Zwölf Defekte (21,4 %) befanden sich an den oberen Extremitäten. In zwei Fällen (3,6 %) wurde die Matriderm(®) -Matrix verwendet, um Nerven von unmittelbar angrenzenden chirurgischen Implantaten zu schützen.

ERGEBNISSE

Bei 41 Patienten (73,2 %) kam es zur Einheilung des Transplantats ohne Komplikationen. Fünfzehn Patienten (26,8 %) zeigten eine gestörte Wundheilung nach Defektverschluss, die unter konservativer Therapie zur Ausheilung gebracht werden konnte. Ein Patient (1,8 %) zeigte ein Transplantatversagen, was eine Revisionsoperation erforderlich machte. Umfangreiche plastische Rekonstruktionen mussten bei keinem Patienten angewandt werden.

SCHLUSSFOLGERUNGEN

Bei Fällen, in denen ausgedehnte plastische Operationen nicht möglich oder nicht erwünscht sind, ist die Verwendung von Dermisersatzpräparaten in Kombination mit Spalthauttransplantationen eine vielversprechende Alternative zum Wundverschluss bei ausgedehnten Weichteilschäden.

Double-layered collagen graft to the radial forearm free flap donor sites without skin graft

Background

Radial forearm free flap is the most reliable flap for intraoral soft tissue reconstruction after cancer ablation surgery. However, unesthetic scar of the donor site and the need for a second donor site for skin graft are major disadvantages of the forearm flap. The purpose of this study was to report the clinical results of double-layered collagen graft to the donor site of the forearm free flap without skin graft.

Methods

Twenty-two consecutive patients who underwent oral cancer ablation and forearm reconstruction between April 2010 and November 2013 were included in this study. Male to female ratio was 12:10, and average age was 61.0 years old (27–84). Double-layered collagen was grafted to the donor site of the forearm free flap and healed for secondary intention. Upper silicone had been trimmed at the periphery during secondary intention, and dry dressing was used. Postoperative scar healing and esthetic results and function were evaluated.

Results

An average follow-up period was 34.9 months. The scar area was decreased to 63.9 % in average. The complete healing was obtained between 1.5 and 3 months according to the defect size. There was no functional defect or impairment 3 months after operation. All patients were satisfied with the esthetic results. Three patients died of recurred cancer.

Conclusions

Double-layered collagen graft was successfully performed in this study. Without the thigh skin graft, patients had experienced less painful postoperative healing periods and discomfort.

Scarring, stem cells, scaffolds and skin repair

The treatment of full thickness skin loss, which can be extensive in the case of large burns, continues to represent a challenging clinical entity. This is due to an on-going inability to produce a suitable tissue engineered substrate that can satisfactorily replicate the epidermal and dermal in vivo niches to fulfil both aesthetic and functional demands. The current gold standard treatment of autologous skin grafting is inadequate because of poor textural durability, scarring and associated contracture, and because of a paucity of donor sites in larger burns. Tissue engineering has seen exponential growth in recent years with a number of 'off-the-shelf' dermal and epidermal substitutes now available. Each has its own limitations. In this review, we examine normal wound repair in relation to stem/progenitor cells that are intimately involved in this process within the dermal niche. Endothelial precursors, in particular, are examined closely and their phenotype, morphology and enrichment from multiple sources are described in an attempt to provide some clarity regarding the controversy surrounding their classification and role in vasculogenesis. We also review the role of the next generation of cellularized scaffolds and smart biomaterials that attempt to improve the revascularisation of artificial grafts, the rate of wound healing and the final cosmetic and functional outcome.

Management of neck contractures by single-stage dermal substitutes and skin grafting in extensive burn patients

Purpose

Severe neck contracture is a problem that must be resolved by priority. We consider the best contracture treatment to be the full-thickness skin graft. However, clinicians often encounter patients, especially extensive burn patients, who have insufficient donor sites for the full-thickness skin graft. We treated extensive burn patients with neck scar contractures with a split-thickness skin graft (STSG) combined with dermal substitutes. The purpose of this study was to evaluate clinical outcomes of neck contracture treatment in extensive burn patients performing STSG with dermal substitutes as adjuvant treatment.

Methods

We analyzed the retrospective clinical and photographic records of 28 patients with severe neck contracture who were admitted to Hallym University Hangang Sacred Heart Hospital, Seoul, Korea, from January 2012 to December 2012. We performed STSG in combination with dermal substitutes to minimize the degree of contracture.

Results

The overall take rate of skin to dermal substitutes was 95.9%, and no grafts failed to affect recontracture except in one patient with a partial loss of artificial dermis who underwent a follow-up skin graft without any problems. Excellent/good outcomes were shown in 27 out of 28 patients.

Conclusion

In extensive burn patients, skin grafting in combination with dermal substitutes can be an alternative to STSG alone for contracture release.

Artificial dermis (Matriderm®) followed by skin graft as an option in dermatofibrosarcoma protuberans with complete circumferential and peripheral deep margin assessment

Dermatofibrosarcoma protuberans (DFSP) is a locally invasive neoplasia with a pattern of infiltrative growth that leads to extended resections. To avoid unnecessary resections and spare tissues, its treatment requires an adequate assessment of the margins. We present a case where artificial dermis (Matriderm®) was used followed by skin graft for reconstruction. We present a 50-year-old woman with a DFSP in the occipital region. She was referred to us after a first surgery with positive margins. A wide local excision with a 2-cm margin was performed and periosteal tissue was also removed, which led to exposure of the skull. Matriderm was placed on the bone surface and dressings were changed every other day. Meanwhile, margins were evaluated by the complete circumferential and peripheral deep margin assessment (CCPDMA) and were positive for DFSP in the superior margin. After 4 weeks the area was completely covered by granulation tissue and a new resection followed by reconstruction with a skin graft was performed. With regard to the difficulties in the margin assessment in DFSP, we present artificial dermis (Matriderm) as an option for reconstructive surgery in these patients, especially when a skin graft cannot be performed as a first option.

The effect of collagen-chitosan porous scaffold thickness on dermal regeneration in a one-stage grafting procedure

Dermal substitutes are used as dermal regeneration templates to reduce scar formation and improve wound healing. Unlike autografts, dermal substitutes lack normal vascular networks. The increased distance required for diffusion of oxygen and nutrients to the autograft following interpositioning of the substitute dramatically affects graft survival. To evaluate the effect of collagen-chitosan scaffold thickness on dermal regeneration, single-layer collagen-chitosan porous scaffolds of 0.5-, 1- and 2-mm thicknesses were fabricated and used to treat full-thickness wounds in a one-stage grafting procedure in a rat model. Skin-graft viability, wound contraction, histological changes, and wound tensile strength were evaluated. The results indicated that the distance for the diffusion of oxygen and nutrients to the autograft in the 2-mm-thick scaffold provided less support for graft take, which resulted in graft necrosis, extensive inflammatory reaction, marked foreign-body reaction (FBR), rapid scaffold degradation, and abnormal collagen deposition and remodeling. In contrast, the thinner scaffolds, especially of that 0.5-mm thickness, promoted earlier angiogenesis, ensuring skin-graft viability with a mild FBR, and ordered fibroblast infiltration and better collagen remodeling. It can be concluded that collagen-chitosan porous scaffolds with a thickness of <1mm are more suitable for dermal regeneration and can be used as dermal templates for treatment of dermal defects using a one-stage grafting procedure.

Matriderm® 1 mm versus Integra® Single Layer 1.3 mm for one-step closure of full thickness skin defects: a comparative experimental study in rats

PURPOSE

Dermal templates, such as Matriderm® and Integra®, are widely used in plastic and reconstructive surgery, often as two-step procedures. A recent development is the application of thin dermal templates covered with split thickness skin grafts in one-step procedures. In this experimental study, we compare the two thin matrices Matriderm® 1 mm and Integra® Single Layer in a one-step procedure with particular focus on neodermis formation.

METHODS

Matriderm® 1 mm and Integra® Dermal Regeneration Template-Single Layer (1.3 mm) were compared in a rat model. In three groups of five animals each, a full thickness wound was covered with (a) Matriderm® 1 mm and neonatal rat epidermis, (b) Integra® Single Layer and neonatal rat epidermis, or, (c) neonatal rat epidermis only (control). Histological sections 2 weeks post transplantation were analyzed with regard to take of template and epidermis, neodermal thickness, collagen deposition, vascularization, and inflammatory response.

RESULTS

Take of both templates was complete in all animals. The Matriderm®-based neodermis was thinner but showed a higher cell density than the Integra®-based neodermis. The other parameters were similar in both matrices.

CONCLUSION

The two templates demonstrate a comparable biological behavior early after transplantation. The only difference was found regarding neodermal thickness, probably resulting from faster degradation of Matriderm®. These preliminary data suggest that both dermal templates appear similarly suitable for transplantation in a one-step procedure.