Skin grafting

Bringing innovative wound care polymer materials to the market: Challenges, developments, and new trends

The development of innovative products for treating acute and chronic wounds has become a significant topic in healthcare, resulting in numerous products and innovations over time. The growing number of patients with comorbidities and chronic diseases, which may significantly alter, delay, or inhibit normal wound healing, has introduced considerable new challenges into the wound management scenario. Researchers in academia have quickly identified promising solutions, and many advanced wound healing materials have recently been designed; however, their successful translation to the market remains highly complex and unlikely without the contribution of industry experts. This review article condenses the main aspects of wound healing applications that will serve as a practical guide for researchers working in academia and industry devoted to designing, evaluating, validating, and translating polymer wound care materials to the market. The article highlights the current challenges in wound management, describes the state-of-the-art products already on the market and trending polymer materials, describes the regulation pathways for approval, discusses current wound healing models, and offers a perspective on new technologies that could soon reach consumers. We envision that this comprehensive review will significantly contribute to highlighting the importance of networking and exchanges between academia and healthcare companies. Only through the joint of these two actors, where innovation, manufacturing, regulatory insights, and financial resources act in harmony, can wound care products be developed efficiently to reach patients quickly and affordably.

To Mesh or Not to Mesh: What Is the Ideal Meshing Ratio for Split Thickness Skin Grafting of the Lower Extremity?

Split-thickness skin grafts can provide effective autologous wound closure in patients with dysvascular comorbidities. Meshing the graft allows for reduced donor site morbidity and expanded coverage. This study directly compares outcomes across varying meshing ratios used to treat chronic lower extremity wounds. Patients who received split-thickness skin grafts to their lower extremity for chronic ulcers from December 2014 to December 2019 at a single center were retrospectively reviewed. Patients were stratified by meshing ratios: nonmeshed (including pie crusting), 1.5:1, and 3:1. The primary outcome was clinical "healing" as determined by surgeon discretion at 30 days, 60 days, and the latest follow-up. Secondary outcomes included postoperative complications, graft loss, ulcer recurrence, progression to amputation, and mortality. A total of 321 patients were identified. Wound sizes and location differed significantly, with 3:1 meshing applied to the largest wounds (187.8 ± 157.6 cm2; 1.5:1 meshed, 110.4 ± 103.9 cm2; nonmeshed 38.7 ± 55.5 cm2; p < .0001) mostly of the lower leg (n = 18, 75%; 1.5:1 meshed, n = 23, 43.4%; nonmeshed n = 62, 25.7%; p < .0001). Meshed grafts displayed a significantly higher proportion of healing at 30 and 60 days, but no differences persisted by the final follow-up (16.5 ± 20.5 months). Longitudinally, nonmeshed STSG was associated with most graft loss (46, 19.1%; p = .011) and ulcer recurrence (44, 18.3%; p = .011). Of the 3 meshing ratios, 3:1 exhibited the lowest rates of complications. Our results suggest that 3:1 meshing is a safe option for coverage of large lower extremity wounds to minimize donor site morbidity.

Donor Age and Time in Culture Affect Dermal Fibroblast Contraction in an In Vitro Hydrogel Model

Current cellular hydrogel-based skin grafts composed of human dermal fibroblasts and a hydrogel scaffold tend to minimize contraction of full-thickness skin wounds and support skin regeneration. However, there has been no comparison between the sources of the dermal fibroblast used. Products using human adult or neonatal foreskin dermal fibroblasts are often expanded in vitro and used after multiple passages without a clear understanding of the effects of this initial production step on the quality and reproducibility of the cellular behavior. Based on the known effects of 2D tissue culture expansion on cellular proliferation and gene expression, we hypothesized that differences in donor age and time in culture may influence cellular properties and contractile behavior in a fibroblast-populated collagen matrix. Using porcine skin as a model based on its similarity to human skin in structure and wound healing properties, we isolated porcine dermal fibroblasts of three different donor ages for use in a 2D proliferation assay and in a 3D cell-populated collagen matrix contractility assay. In 2D cell culture, doubling time remained relatively consistent between all age groups from passage 1 to 6. In the contractility assays, fetal and neonatal groups contracted faster and generated more contractile force than the adult group at passage 1 in vitro. However, after five passages in culture, there was no difference in contractility between ages. These results show how cellular responses in a hydrogel scaffold differ based on donor age and time in culture in vitro, and suggest that consistency in the cellular component of bioengineered skin products could be beneficial in the biomanufacturing of consistent, reliable skin grafts and graft in vivo models. Future research and therapies using bioengineered skin grafts should consider how results may vary based on donor age and time in culture before seeding. Impact statement Little is known about the impact of donor cell age and time in culture on the contraction of cellular, hydrogel-based skin grafts. These results show how cellular phenotypes of porcine fibroblasts differ based on donor age and time in culture. This information is beneficial when addressing important inconsistencies in biomanufacturing of bioengineered skin grafts and in vitro models. These findings are relevant to research and therapies using bioengineered skin graft models and the results can be used to increase reproducibility and consistency during the production of bioengineered skin constructs. The information from this study can be extrapolated to future in vivo studies using human dermal fibroblasts in an in vivo model to help determine the best donor age and time in culture for optimal wound healing outcomes or more reproducible in vitro testing constructs.

Recent Progress on Heparin–Protamine Particles for Biomedical Application

Biomolecules are attractive building blocks with self-assembly ability, structural diversity, and excellent functionality for creating artificial materials. Heparin and protamine, a clinically relevant pair of biomolecules used in cardiac and vascular surgery, have been shown to coassemble into particulate polyelectrolyte complexes in vitro. The resulting heparin–protamine particles exhibit adhesive properties that enable advantageous interactions with proteins, cells, and various other substances and have been employed as functional materials for biomedical applications. In this review article, we summarize recent progress in research on the use of heparin–protamine particles as drug carriers, cell adhesives, and cell labels. Studies have demonstrated that heparin–protamine particles are potentially versatile in biomedical fields from drug delivery and regenerative medicine to plastic surgery.

Epidemiology and Outcome Analysis of 470 Patients with Hand Burns: A Five-Year Retrospective Study in a Major Burn Center in Southwest China

Background

This retrospective study aimed to investigate the epidemiology of burns to the hand, including the causes, demographic data, management, and outcome in a single center in Southwest China between 2012 and 2017.

Material/Methods

A retrospective study included 470 patients with hand burns who were treated at a single hospital in Southwest China between 2012 and 2017. Demographic, injury-related, and clinical data were obtained from the clinical electronic data collection system.

Results

In 470 patients, men were more commonly admitted to hospital with hand burns (73.62%). Children under 10 years (29.57%) were the main patient group. Hospital admissions occurred in the coldest months, from December to March (55.11%). In 60.21% of cases, hand burns occurred outside the workplace. Fire (40.42%), electricity (30.85%), and hot liquids (20.21%) were the main causes of hand burns. Data from 428 patients showed that burns with a larger total body surface area and deeper burns were associated with surgery and amputation. Burn depth was a risk factor for skin grafting, and lack of burn cooling before hospital admission increased the risk of amputation. Data from 117 patients with localized burns showed that full-thickness burns and lack of cooling before admission were associated with an increased hospital stay.

Conclusions

The findings suggest that in Southwest China, prevention programs for children aged 0–9 years, injuries occurring in winter and non-workplace sites, and fire burns were imperative.

Enhancing Skin Grafts with Primed Gingival Mesenchymal Stromal Cells

Injuries of the largest anatomical organ, the skin, resulting from trauma, burns, or inflammatory disorders can lead to devastating health effects. Modern approaches to re-establishing critical barrier functions have evolved from simple biomaterial dressings to sophisticated skin grafts. A report by Magne et al. (2019) describes the exciting use of IL-1β-pretreated gingival mesenchymal stem cells to enhance skin graft functions.

Cell-free fat extract promotes tissue regeneration in a tissue expansion model

Background

Tissue expansion techniques play an important role in plastic surgery. How to improve the quality of the expanded skin and shorten the expansion period are still worth investigating. Our previous studies found that a cell-free fat extract (CEFFE) possessed pro-angiogenic and pro-proliferative activities. However, the role of CEFFE on tissue expansion has remained unclear. The purpose of this study was to evaluate the effect of CEFFE on tissue expansion.

Methods

A rat tissue expansion model was used. Animals were treated with CEFFE by subcutaneous injection. After 4 weeks of tissue expansion, the skin necrosis and retraction rates were evaluated, the thicknesses of the epidermis and dermis were determined by histological analyses, blood vessel density was measured by anti-CD31 staining, cell proliferation was assessed by proliferating cell nuclear antigen staining, and the expression of specific proteins was evaluated by western blot analyses. In addition, the effects of CEFFE on the proliferation and cell cycle of cultured HaCaT cells were evaluated in vitro.

Results

CEFFE treatment significantly decreased the necrosis rate and retraction of the expanded skin. The thickness of the epidermal and dermal layers was higher in CEFFE-treated compared to untreated skin. The density of blood vessels and cell proliferation in the epidermis of the expanded skin was improved by CEFFE treatment. In addition, CEFFE treatment significantly increased the expression of the vascular endothelial growth factor receptor, epidermal growth factor receptor, collagen type 1, and collagen type 3. CEFFE also increased the proliferation of HaCaT cells in culture.

Conclusions

CEFFE improves the quality of the expanded skin by promoting angiogenesis and cell proliferation. It could be potentially used clinically for augmenting tissue expansion.

Cold atmospheric plasma modulates endothelial nitric oxide synthase signalling and enhances burn wound neovascularisation

Treatment with cold atmospheric plasma (CAP) has been reported to promote wound healing in animals. However, how this process is mediated remains unclear. In this study we examined the mechanisms which underlie the improved wound healing effects of CAP and the roles of associated reactive oxygen and nitrogen species (RONS), which are generated by plasma. By using in vitro models which mimicked various steps of angiogenesis, we demonstrated that CAP triggered the production of nitric oxide (NO), and enhanced cell migration and the assembly of endothelial cells into vessel-like structures. These are both hallmarks of the proliferative phase of wound healing. Using a mouse model of a third-degree burn wound, we went on to show that CAP treatment was associated with enhanced angiogenesis, characterised by accelerated in vivo wound healing and increased cellular proliferation. Here, CAP significantly increased the in vivo production of endothelial NO synthase (eNOS), an enzyme that catalyses NO synthesis in endothelial cells, and significantly increased the expression of pro-angiogenic PDGFRβ and CD31 markers in mouse wounds. Mechanistically, we showed that CAP induced eNOS phosphorylation and activation, thereby increasing the levels of endogenous NO in endothelial cells. Increased NO generation facilitated by CAP further stimulated important pro-angiogenic VEGFA/VEGFR2 signalling in vitro. This proof-of-concept study may guide future efforts aimed at addressing the use of physical plasma and its therapeutic applications in a variety of pathological scenarios. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Adipose-derived stem cells improve full-thickness skin grafts in a rat model

To investigate the effects of heterologous adipose-derived stem cells (ADSCs) on autologous full-thickness skin grafts, we designed a first-intention healing model using Wistar rats. We harvested and sutured two full-thickness skin grafts in the dorsal recipient beds of 15 rats, randomized into three groups. In the treatment group, 1 × 10⁶ ADSCs resuspended in saline solution (200 μL) were administered subcutaneously to the skin graft. The control group received only saline solution subcutaneously, whereas the negative control group did not receive any treatment. Compressive dressings were maintained until postoperative day 5. The grafts were assessed by two observers, who checked for the presence of epidermolysis on day 14. Planimetry showed the relative areas of normal skin, redness, ulceration, and contraction. Graft samples were obtained on day 14 and stained with hematoxylin and eosin and Masson's trichrome. Epidermal analysis evaluated thickening, keratosis, acanthosis, hydropic degeneration, and inflammatory infiltrate. Dermal evaluation investigated the absence of hair follicles, granulation tissue formation, presence of inflammatory infiltrate, and collagen deposition. Immunohistochemistry was performed for dermal anti-VEGF and epidermal anti-Ki-67 staining. The ADSC group presented better macroscopic aspects, lower incidence of epidermolysis, and less loss of hair follicles. In addition, the ADSC group presented the lowest frequency of histopathological changes in the dermis and epidermis, as well as the largest subcutaneous and granulation tissue VEGF averages and the weakest Ki-67 staining of the epidermal basal layer. Subcutaneous administration of ADSCs may improve the integration of skin grafts, reducing the deleterious effects of ischemia and reperfusion injury.

Split-thickness skin grafting: early outcomes of a clinical trial using different graft thickness

OBJECTIVE

In clinical practice, split-thickness skin graft (STSG) transplantation remains the gold standard for covering large skin defects. Currently, there is no consensus on the optimal thickness of skin grafts. The purpose of our study was to compare the early healing processes of recipient and donor wounds after STSG transplantation using grafts of different thickness.

METHOD

This prospective, randomised clinical trial included 84 patients that underwent STSG transplantation surgery for post-burn, post-traumatic or postoperative skin defects. Patients were randomised to receive a skin graft of either 0.2mm, 0.3mm or 0.4mm thickness. After skin transplantation, the wound healing parameters of both the recipient and donor wounds were evaluated after three days, one week, two weeks and one month.

RESULTS

The greatest mean epithelialisation scores and highest rate of complete wound epithelialisation were identified in the recipient and donor wounds of the 0.2mm transplant group, at all time points. When the recipient wound pain scores were evaluated, the greatest visual analogue scale (VAS) values were found in the 0.2mm transplant group. The opposite result was found for the donor wound, where the highest VAS scores were identified in the 0.4mm transplant group. There were no significant differences, at any follow-up period, when wound secretion, erythema, swelling, localised warmth and fluctuation were compared.

CONCLUSION

The early healing of recipient wounds after STSG transplantation with grafts of various thickness differed considerably, especially regarding wound epithelialisation and pain.

Skin grafting for the treatment of chronic leg ulcers - a systematic review in evidence-based medicine

Skin grafting is one of the most common surgical procedures in the area of non-healing wounds by which skin or a skin substitute is placed over a wound to replace and regenerate the damaged skin. Chronic leg ulcers are an important problem and a major source of expense for Western countries and for which many different forms of treatment have been used. Skin grafting is a method of treatment that decreases the area of chronic leg ulcers or heals them completely, thus improving a patient's quality of life. Skin grafting is an old technique, rediscovered during the first and second world wars as the main treatment for wound closure. Nowadays, skin grafting has a pivotal role in the context of modern wound healing and tissue regeneration. The aim of this review was to track and to analyse the specific outcomes this technique achieved, especially in the last decade, in relation to venous, arterial, diabetic, rheumatoid and traumatic leg ulcers. Our main findings indicate that autologous split-thickness skin grafting still remains the gold standard in terms of safety and efficacy for chronic leg ulcers; skin grafting procedures have greater success rates in chronic venous leg ulcers compared to other types of chronic leg ulcers; skin tissue engineering, also supported by genetic manipulation, is quickly expanding and, in the near future, may provide even better outcomes in the area of treatments for long-lasting chronic wounds.

Eyelid Reconstruction with Full Thickness Skin Grafts After Carcinoma Excision

BACKGROUND

Various techniques have been proposed for reconstruction of the eyelid anterior lamella after carcinoma excision: among these are the transposition of skin flaps, and full-thickness skin grafts or combination of these two.

AIM

To present our experience in eyelid reconstruction with full-thickness skin grafts and to assess the aesthetic and functional outcomes.

PATIENTS AND METHODS

The present retrospective study included 39 patients (20 males, 19 females, mean age 71 yrs) with surgically excised eyelid carcinoma, followed by reconstruction using full-thickness skin grafts. The patients were treated between 2005 and 2014. Parameters recorded were patient demographics, histological classification of malignancy, tumor localization and size, postoperative defect size. In cases of large full-thickness lower lid defect Hughes tarsoconjunctival flap was used for reconstruction of posterior lamella. Full-thickness skin grafts donor sites included upper eyelid, preauricular area and inner brachial area. We appraised the grafts viability one week after surgery and the aesthetic results - 6 months after surgery by the graft colour and lid position.

RESULTS

In 95% of the cases the skin grafts were viable. The full-thickness skin graft (FTSG) failed in two patients because of subcutaneous haematoma. There were a few early postoperative complications including graft hypertrophy, graft contraction, and partial graft failure, which were managed without additional surgery. All 39 patients had normal postoperative lid function. All 39 had either good (14) or excellent (25) cosmetic results.

CONCLUSIONS

Our findings suggest that full-thickness skin graft is a good choice in periocular reconstructive surgery after carcinoma excision. The surgical technique is easy to perform producing proper functional and aesthetic results.

Grafix®, a Cryopreserved Placental Membrane, for the Treatment of Chronic/Stalled Wounds

Objective: To discuss the use of Grafix®, a commercially available, cryopreserved placental membrane, for the treatment of chronic/stalled wounds of different etiologies. Approach: To describe the unique composition of Grafix, to provide an overview of the existing clinical evidence supporting the benefits of Grafix for wound treatment, and to share the experience of the South Shore Hospital Center for Wound Healing (Weymouth, MA) with Grafix for the treatment of nonhealing wounds. Results: Clinical evidence supports the safety and efficacy of Grafix for the treatment of chronic/stalled wounds, including those that have failed other advanced treatment modalities. Innovation: Grafix is a cryopreserved placental membrane manufactured utilizing a novel technology that enables the preservation of all placental membrane components in their native state. Placental membranes have a unique composition of extracellular matrix, growth factors, and cells (including mesenchymal stem cells), which makes this tissue unique among other advanced biological wound treatment modalities. Conclusion: Clinical evidences support the benefits of Grafix for head-to-toe wound treatment.

Full thickness skin grafts in periocular reconstructions: long-term outcomes

PURPOSE

To evaluate the outcomes of eyelid reconstruction in patients who underwent full thickness skin grafts.

METHODS

A retrospective, noncomparative intervention study of patients who underwent periocular reconstruction with full thickness skin grafts between 2005 and 2011.

RESULTS

One hundred consecutive Caucasian patients were included in the study, 54 women and 46 men. Mean follow up was 32 months. Indications for full thickness skin grafts were excision of eyelid tumors (98%) and cicatricial ectropion (2%). Site of lid defects were lower lid (60%), medial canthus (32%), upper lid (6%), and lateral canthus (2%). The skin graft donor sites were supraclavicular (44%), upper eyelid (24%), inner brachial (18%), and postauricular (14%).Early postoperative complications included lower eyelid graft contracture (1%) and partial failure (1%). Late sequelae included lower eyelid graft contracture (4%) and hypertrophic scarring (23%). Of the 23 patients with hypertrophic scar, 21 achieved good outcomes following massage with silicone gel and steroid ointment and 2 had persistent moderate lumpiness. No statistically significant association was found between graft hypertrophy and donor site or graft size. As high as 95% of all patients achieved good final eyelid position. Good color match was seen in 94% and graft hypopigmentation in 6%. An association between hypopigmentation and supraclavicular and inner brachial donor site was found to be statistically significant.

CONCLUSIONS

Most patients (94%) achieved good eyelid position and color match. Majority (91%) of the early postoperative cicatricial sequelae can be reversed by massage, steroid ointment, and silicone gel application. Full thickness skin grafts have excellent graft survival rates and have minimal donor site morbidity.

Mohs micrographic surgery of the eyelid: an overview of anatomy, pathophysiology, and reconstruction options

BACKGROUND

Mohs micrographic surgery (MMS) is the ideal treatment for skin cancer removal. The advantages of MMS in the eyelid area include its high cure rate, tissue-sparing effects, and overall cost effectiveness.

OBJECTIVE

To review eyelid anatomy, detail ocular tumors that are amenable to MMS, and examine the surgical repair options commonly used in this area.

MATERIALS AND METHODS

A review of the literature on MMS of the eyelid was performed with specific reference to ocular anatomy, eyelid malignancy types, and surgical reconstruction.

CONCLUSION

Eyelid function is critical for the maintenance of ocular health and vision. MMS is an ideal skin cancer treatment for the delicate structure of the eyelid, where maximal tissue preservation is critical. There are a plethora of reconstruction options to consider after MMS has been performed in this area. The choice of repair and surgical outcome depend, in part, on the surgeon's knowledge of eyelid anatomy and his or her ability to assess the repair requirements of the post-MMS defect. Dermatologic surgeons can effectively work with other specialists to help ensure that their patients receive a cure with restored ocular function and optimal cosmesis.

Strategies for tissue and organ decellularization

Decellularized tissues have been successfully used in a variety of tissue engineering/regenerative medicine applications, and more recently decellularized organs have been utilized in the first stages of organ engineering. The protocols used to decellularize simple tissues versus intact organs differ greatly. Herein, the most commonly used decellularization methods for both surgical mesh materials and whole organs are described, with consideration given to how these different processes affect the extracellular matrix and the host response to the scaffold.

Marjolin's ulcer of the leg secondary to nonhealing chronic venous stasis ulcer

We report on a 79-year-old man with a chronic venous stasis ulceration of >20 years' duration in the left medial leg presenting to our clinic after admission for bleeding and suspected infection of his ulceration. This lesion had been biopsied in 1999 and was found to be a benign, chronic venous insufficiency ulceration. Plain film radiographs as well as a bone scan did not identify osteomyelitis. Because of the hypertrophic, nodular appearance of this ulceration, it was the clinicians' discretion to perform a repeat biopsy of the lesion. Biopsy revealed invasive, well-differentiated squamous cell carcinoma. A computed tomography scan subsequently identified a suspicious inguinal lymph node, and an ultrasound-guided needle aspiration revealed metastatic squamous cell carcinoma of the biopsied lymph node. Above-knee amputation was indicated at this time and was performed in conjunction with local superficial inguinal lymph node resection, after which the patient was discharged from our service.

Skin graft

Skin graft is one of the most indispensable techniques in plastic surgery and dermatology. Skin grafts are used in a variety of clinical situations, such as traumatic wounds, defects after oncologic resection, burn reconstruction, scar contracture release, congenital skin deficiencies, hair restoration, vitiligo, and nipple-areola reconstruction. Skin grafts are generally avoided in the management of more complex wounds. Conditions with deep spaces and exposed bones normally require the use of skin flaps or muscle flaps. In the present review, we describe how to perform skin grafting successfully, and some variation of skin grafting.

Wound-healing factors secreted by epidermal keratinocytes and dermal fibroblasts in skin substitutes

Full-skin substitutes, epidermal substitutes, and dermal substitutes are currently being used to heal deep burns and chronic ulcers. In this study, we investigated which wound-healing mediators are released from these constructs and whether keratinocyte-fibroblast interactions are involved. Autologous skin substitutes were constructed from human keratinocytes, fibroblasts, and acellular donor dermis. Full-thickness skin was used to represent an autograft. Secretion of wound-healing mediators was investigated by means of protein array, enzyme-linked immunosorbent assay, neutralizing antibodies, and conditioned culture supernatants. Full-skin substitutes and autografts produce high amounts of inflammatory/angiogenic mediators (IL-6, CCL2, CXCL1, CXCL8, and sST2). Epidermal and dermal substitutes produced less of these proteins. Epidermal-derived proinflammatory cytokines interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha) were found to mediate synergistically the secretion of these wound-healing mediators (with the exception of sST2) from fibroblasts in dermal substitutes. The secretion of proinflammatory cytokines (IL-1alpha, TNF-alpha), chemokine/mitogen (CCL5) and angiogenic factor (vascular endothelial growth factor) by epidermal substitutes and tissue remodeling factors (tissue inhibitor of metalloproteinase-2, hepatocyte growth factor) by dermal substitutes was not influenced by keratinocyte-fibroblast interactions. The full-skin substitute has a greater potential to stimulate wound healing than epidermal or dermal substitutes. Both epidermal-derived IL-1alpha and TNF-alpha are required to trigger the release of dermal-derived inflammatory/angiogenic mediators from skin substitutes.

The Australian Mohs database: short-term recipient-site complications in full-thickness skin grafts

BACKGROUND

There are only a few reports on the outcome with full-thickness skin grafts (FTSG) in defect reconstruction after Mohs micrographic surgery (MMS).

OBJECTIVES

The objective was to evaluate the complications with FTSG in patients treated with MMS for cutaneous tumors.

METHODS

This study is based on a prospective data collection of all patients in Australia treated with MMS and monitored by the Skin and Cancer Foundation, between 1993 and 2002. Primary outcome measures were FTSG recipient-site complications (partial/complete graft failure, graft infection, acute bleeding/hematoma, graft hypertrophy, and graft contracture).

RESULTS

The study group included 2,673 patients (50.2% men) with a mean age of 64+/-14 years. Most tumors were basal call carcinoma (90.9%) and were located on the nose (63.8%), periocular area (14.8%), or auricular area (8.1%). A total of 11.7% of cases had recipient-site complications (graft hypertrophy, 42.3%; partial graft failure, 27.2%; graft contraction, 15.3%). Only 45.2% of complicated cases required treatment.

CONCLUSION

Short-term recipient-site complications occurred in less than 12% of reconstructions with FTSG. Graft hypertrophy and partial graft failure accounted for most cases of complications. The authors have indicated no significant interest with commercial supporters.

Erbium:YAG laser-assisted preparation of a combined dermal/full thickness sandwich skin graft

BACKGROUND

Skin grafting is a common procedure to close defects after tumor resection. However, delicate areas such as the heel or the sole of the foot can be closed with a specially designed graft as described in this article.

OBJECTIVE

To describe a surgical technique by means of erbium:YAG laser-assisted preparation of a combined dermal/full-thickness sandwich skin graft that facilitates the closure of defects, especially at mechanically stressed anatomic sites.

METHODS

Tumor defects on the sole of the foot of 28 patients were closed with a new dermal/full-thickness sandwich skin graft. To obtain this special graft, half of a full-thickness skin graft twice the size of the wound defect was deepithelialized with an erbium:YAG laser. After complete defatting of the transplant, the deepithelialized part was folded beneath the full-thickness part (upside down) resulting in a sandwich graft, enabling contact of the papillary dermis with the wound surface. Graft results were graded as excellent when more than 75%, good if 50-75%, fair if 25-50%, and poor if less than 25% of the transplant healed.

RESULTS

Results were graded as excellent in 32%, good in 54%, fair in 11%, and poor in 3% of the patients. Total graft loss was experienced in 1 of 28 patients. Complications such as bulky margins or infection were encountered in 14% of the patients.

CONCLUSION

The laser-assisted preparation of the combined dermal/full-thickness sandwich skin graft is a new technique that facilitates the closure of defects in delicate anatomic locations with high mechanical stress like the plantar sole.

Use of a bioengineered skin equivalent for the management of difficult skin defects after pediatric multivisceral transplantation

BACKGROUND

Primary wound closure is not always possible after pediatric multi-visceral transplantation because of oversized donor organs and/or intestinal or graft edema. We report our experience evaluating the safety and efficacy of Graftskin (Apligraf, Organogenesis, Canton, Mass), a bioengineered bi-layered human skin equivalent, for the management of difficult skin abdominal defects after multivisceral transplantation in a pediatric population.

METHODS

A retrospective chart review was performed of pediatric multivisceral transplantation patients who were treated with Graftskin. Adverse events, course of wound reepithelialization, and time for complete closure were recorded.

RESULTS

Four patients, 7 to 29 months old, were treated with Graftskin. One patient died because of unrelated reasons. Stimulation of the granulation, reepithelialization, and rapid reduction of the wound surface and depth occurred in the other 3 patients. Complete reepithelialization occurred within 5 months. No adverse events were noted.

CONCLUSION

Graftskin was a successful treatment for difficult abdominal skin defects after liver and multivisceral transplantation in children.

Incidence of host site complications in periocular full thickness skin grafts

AIM

To evaluate the complications of periocular full thickness skin grafts (FTSG) in patients treated with Mohs' micrographic surgery (MMS) for periocular malignancy.

METHOD

This prospective, multicentre case series included all patients in Australia treated with MMS for periocular malignancy followed by reconstruction with FTSG, who were monitored by the Skin and Cancer Foundation, between 1993 and 1999. The parameters recorded were patient demographics, reason for referral, histological classification of malignancy and evidence of perineural invasion, duration of tumour, site, recurrences prior to MMS, preoperative tumour size, and postoperative defect size. FTSG donor sites included upper lid, preauricular, retroauricular, inner brachial, and supraclavicular. The primary outcome measures were FTSG host site complications (partial/complete graft failure, graft infection, acute bleeding/haematoma, graft hypertrophy, and graft contracture).

RESULTS

397 patients (229 males, 168 females), mean age 60 (SD 15) years (range 20-91 years). 92.7% were diagnosed with basal call carcinoma, 2.0% with Bowen's disease, and 3.3% with squamous cell carcinoma. Medial canthus was involved in 66.5% of patients, lower eyelid in 28.0%, and upper eyelid in 5.5%. Postoperative complications were recorded in 62 patients (15.6% of all patients), and consisted of graft hypertrophy (45.1% of complications), graft contraction (29.1%), and partial graft failure (12.9%). The only statistically significant association found was a higher rate of graft hypertrophy in medial canthal reconstruction (p = 0.007).

CONCLUSION

Host site complications of periocular FTSG are not common. Graft hypertrophy accounted for most complications and was more common in the medial canthal area. No other variables such as patient demographics, tumour characteristics, or donor site factors were associated with a higher risk of complications.

Organotypic cultures of autologous hair follicle keratinocytes for the treatment of recurrent leg ulcers

Our purpose was to evaluate, in an open study, the efficacy of epidermal equivalents (EEs), a tissue-engineered epidermis prepared from autologous hair follicle keratinocytes, for the treatment of recurrent leg ulcers (n = 50). To generate EEs, keratinocytes expanded from the outer root sheaths of plucked anagen hair follicles were seeded on cell culture inserts at air-liquid interface. The total culture time was 5 to 6 weeks. Three days after the procedure, 95% of EEs adhered to the wound bed. After 8 weeks, 70% of the total wound surface was re-epithelialized and 32% of the ulcers were healed. After applying the EEs, a major relief of wound pain was noticed by the patients. EEs were applied in ambulatory patients without surgical facilities. Because 92% of the cases included in this study presented a recurrence of their ulcers after a split-thickness skin graft, we consider these ulcers as difficult to treat and propose the EEs as an alternative effective treatment of recurrent leg ulcers.