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

Bioengineered Skin for Diabetic Foot Ulcers: A Scoping Review

Diabetic foot ulcers (DFUs) pose a significant threat to individuals with diabetes mellitus (DM), such as lower limb amputation and severe morbidity. Bioengineered skin substitutes (BSS) are alternatives to traditional interventions for treating DFUs, but their efficacy compared to standard wound care (SWC) or other treatment types, such as allografts, remains unknown. A scoping review of human studies was conducted to identify current approaches in the treatment of DFUs using BSS as compared with other treatment options. Systematic searches in PubMed, Cochrane Library, and Web of Science were conducted to identify comparative studies that enrolled 10 or more patients and evaluated wound healing outcomes (closure, time-to-healing, and area reduction). Database searches isolated articles published from 1 December 2012 to 1 December 2022 and were conducted in accordance with PRISMA-ScR guidelines. The literature search yielded 1312 articles, 24 of which were included for the qualitative analysis. Findings in these studies demonstrated that BSS outperformed SWC in all measured outcomes, suggesting that BSS may be a superior treatment for DFUs. Of the 24 articles, 8 articles compared human amniotic membrane allografts (hAMA) to BSS. Conflicting evidence was observed when comparing BSS and hAMA treatments, highlighting the need for future research.

Perioperative Antibiotikaprophylaxe in der Dermatochirurgie - Positionspapier der Arbeitsgruppe Antibiotic Stewardship der Deutschen Gesellschaft für Dermatochirurgie (DGDC), Teil 2: Spezielle Indikationen und Situationen

Neben der Vermeidung postoperativer Wundinfektionen nach dermatochirurgischen Eingriffen hat die perioperative Antibiotikaprophylaxe (PAP) das Ziel, das Auftreten weiterer postoperativer Infektionskomplikationen, insbesondere der bakteriellen Endokarditis oder hämatogener Gelenkprotheseninfektionen, zu verhindern. In der vorliegenden Arbeit werden spezielle Situationen dargestellt, in denen eine PAP notwendig werden kann. So benötigen Patienten nach Herzklappenersatz jeglicher Art, einschließlich Transkatheter‐Klappenersatz oder bei Verwendung von Prothesenmaterial zur Herzklappenkorrektur, oder Patienten nach einer durchgemachten bakteriellen Endokarditis bei zweizeitigen dermatochirurgischen Eingriffen, Eingriffen an der Schleimhaut oder ulzerierten Tumoren eine PAP.

Auch die Anwendung einer PAP in speziellen Situationen wie bei sekundärer Wundheilung, septischen dermatochirurgischen Eingriffen oder Ulcus cruris‐Chirurgie werden in dieser Arbeit anhand der aktuellen wissenschaftlichen Literatur ausführlich dargestellt und diskutiert. Die vorliegende Arbeit ist der 2. Teil des Positionspapiers der Arbeitsgruppe Antibiotic Stewardship der Deutschen Gesellschaft für Dermatochirurgie und formuliert evidenzbasierte Empfehlungen für die Verabreichung einer PAP bei dermatochirurgischen Eingriffen bei speziellen Indikationen und Situationen. Dies ist von besonderer Wichtigkeit, da bei dermatochirurgischen Eingriffen, wie im ersten Teil dargelegt, im Regelfall auf eine PAP verzichtet werden kann und sollte.

Perioperative antibiotic prophylaxis in skin surgery - Position paper of the Antibiotic Stewardship working group of the German Society for Dermatologic Surgery (DGDC), Part 2: Special indications and situations

In addition to prevention of surgical site infections after skin surgery, perioperative antibiotic prophylaxis (PAP) aims to prevent the occurrence of other postoperative infectious complications, especially bacterial endocarditis and hematogenous joint prosthesis infections. This article discusses specific indications for the use of PAP. For example, patients who have undergone any type of heart valve replacement, including transcatheter valve replacement or use of prosthetic material to correct the heart valve, or patients who have experienced bacterial endocarditis, require PAP during skin surgery on mucosal membranes or ulcerated tumors. The use of PAP in special situations such as secondary wound healing, septic dermatosurgery or ulcer surgery is also presented and discussed in detail in this paper based on the current scientific literature. This paper represents the second part of the position paper of the Antibiotic Stewardship Working Group of the German Society for Dermatologic Surgery (DGDC) and summarizes evidence-based recommendations for the administration of PAP during skin surgery for special indications and situations. This is particularly important because, as detailed in Part 1 of this position paper, PAP can and usually should be avoided in skin surgery.

No More Venous Ulcers-What More Can We Do?

Venous leg ulcers (VLUs) are the most severe complication caused by the progression of chronic venous insufficiency. They account for approximately 70-90% of all chronic leg ulcers (CLUs). A total of 1% of the Western population will suffer at some time in their lives from a VLU. Furthermore, most CLUs are VLUs, defined as chronic leg wounds that show no tendency to heal after three months of appropriate treatment or are still not fully healed at 12 months. The essential feature of VLUs is their recurrence. VLUs also significantly impact quality of life and could cause social isolation and depression. They also have a significant avoidable economic burden. It is estimated that the treatment of venous ulceration accounts for around 3% of the total expenditure on healthcare. A VLU-free world is a highly desirable aim but could be challenging to achieve with the current knowledge of the pathophysiology and diagnostic and therapeutical protocols. To decrease the incidence of VLUs, the long-term goal must be to identify high-risk patients at an early stage of chronic venous disease and initiate appropriate preventive measures. This review discusses the epidemiology, socioeconomic burden, pathophysiology, diagnosis, modes of conservative and invasive treatment, and prevention of VLUs.

Natural Polymer-Based Thin Film Strategies for Skin Regeneration in Lieu of Regenerative Dentistry

Wound healing (WH) is a complex and dynamic process that comprises of a series of molecular and cellular events that occur after tissue injury. The injuries of the maxillofacial and oral region caused by trauma or surgery result in undesirable WH such as delayed wound closure and formation of scar tissue. Skin tissue engineering (TE)/regeneration is an emerging approach toward faster, superior, and more effective resolution of clinically significant wounds effectively. A multitude of TE principles approaches are being put to action for the fabrication of hydrogels, electrospun sheets, 3D scaffolds, and thin films that can be used as wound dressings materials, sutures, or skin substitutes. Thin films are advantageous over other materials owing to their flexibility, ability to provide a barrier against external contamination, easy gaseous exchange, and easy monitoring of wounds. This review focuses on wound-dressing films and their significance and discusses various fabrication techniques. In addition, we explore various natural biopolymers that can be used for fabrication of skin TE materials. Impact Statement In this review article, critical evaluations of natural polymers used in skin regeneration were discussed. Further, the fabrication technology of the 2D and 3D material in wound healing were discussed.

Glycolipid Biosurfactants in Skincare Applications: Challenges and Recommendations for Future Exploitation

The 21st century has seen a substantial increase in the industrial applications of glycolipid biosurfactant technology. The market value of the glycolipid class of molecules, sophorolipids, was estimated to be USD 409.84 million in 2021, with that of rhamnolipid molecules projected to reach USD 2.7 billion by 2026. In the skincare industry, sophorolipid and rhamnolipid biosurfactants have demonstrated the potential to offer a natural, sustainable, and skin-compatible alternative to synthetically derived surfactant compounds. However, there are still many barriers to the wide-scale market adoption of glycolipid technology. These barriers include low product yield (particularly for rhamnolipids) and potential pathogenicity of some native glycolipid-producing microorganisms. Additionally, the use of impure preparations and/or poorly characterised congeners as well as low-throughput methodologies in the safety and bioactivity assessment of sophorolipids and rhamnolipids challenges their increased utilisation in both academic research and skincare applications. This review considers the current trend towards the utilisation of sophorolipid and rhamnolipid biosurfactants as substitutes to synthetically derived surfactant molecules in skincare applications, the challenges associated with their application, and relevant solutions proposed by the biotechnology industry. In addition, we recommend experimental techniques/methodologies, which, if employed, could contribute significantly to increasing the acceptance of glycolipid biosurfactants for use in skincare applications while maintaining consistency in biosurfactant research outputs.

Defensins of Lucilia sericata Larvae and Their Influence on Wound Repair Processes in Practical Assessment-A Study of Three Cases

Bacteria inhabiting chronic wounds form a biofilm that prolongs and slows down the healing process. Increasingly common antibiotic resistance requires clinicians to search for effective and alternative treatment methods. Defensins are the most common antimicrobial peptides capable of eradicating pathogens. Their discovery in maggot secretions allowed for a broader understanding of the healing mechanisms, and approving the use of Lucilia sericata fly larvae in the treatment of infected wounds resulted in an effective and safe procedure. The aim of the study was to present the possibility of biofilm elimination in a chronic wound by means of medical maggots (Lucilia sericata) with the example of three selected clinical cases. The observation included three women who met the inclusion criterion of having venous insufficiency ulcers with inhibited regeneration processes. Medical maggots were applied in a biobag for three days, and observation was conducted for 21 consecutive days. In 2 cases, a significant elimination of necrotic tissue from the wound bed with local granulation tissue was observed 72 h after application of a larvae colony on the wounds. In 1 case, the application of the larvae accelerated the repair process by reducing the wound area by approximately 40% at the time of observation. The formation of biofilm in a chronic wound is one of the main causes of disturbances in its effective healing. Combining procedures (scraping, antiseptic compresses, MDT, NPWT) related to wound debridement increases the effectiveness of biofilm elimination. The use of medical maggots is a safe and effective method of choice, and it enhances the processes of debridement. However, confirmed indisputable data on their effectiveness and frequency of use in the process of stimulating healing processes are still not available in the literature.

Fractional Epidermal Skin Grafts in Hard-to-Heal Wounds: Case Series

Cellutome^™ is a minimally invasive, automated system for harvesting fractional epidermal micrografts. This therapy is indicated for granulating, small size, poor exuding acute wounds. We enrolled 15 patients with 9 venous leg ulcers and 6 atypical ulcers. The micrografts were applied with a nonadherent dressing and covered with a polyurethane foam and multilayer bandage. We scheduled 3 weekly visits for the change of the secondary dressings and multilayer bandage and clinical assessment (Wound Bed Score [WBS], pain assessment, and healing rate). The lesions were measured with the Silhouette Star^™ system, a software that allows measurement of perimeter and area from a digital image. The only symptom during the procedure was a sensation of warmth. The donor area healed in 2 weeks in all patients (n = 15). We reported an area reduction of 24.30% in typical ulcers and 38.82% in atypical ulcers after 3 weeks. The average WBS improved in all ulcers from 13.06 to 14.93. The average healing rate was 0.19 mm/day both in typical and atypical ulcers. Consequently, in our small case series fractionated epidermal graft treatment significantly promoted the healing rate in all chronic ulcers regardless of etiology. Future studies with larger case series will be needed.

Biomarkers of Skin Graft Healing in Venous Leg Ulcers

There is a need for biomarkers that predict the success of transplantation of venous leg ulcers (with autologous split-thickness skin grafts). The primary objective of this exploratory study was to investigate the association between split-thickness skin graft healing in venous leg ulcers and candidate wound fluid biomarkers representing inflammatory cell and endogenous proteinase activities, and bioactivity. A secondary objective was to compare biomarker levels of the 17 venous leg ulcers with sterile split-thickness skin graft donor-site wounds in another 10 patients with venous leg ulcers. Wound fluids were collected for 24 h using a validated method. The concentration of pre-operative matrix metalloproteinase-9 in wound fluid was higher in venous leg ulcers showing good healing (n = 10) than in venous leg ulcers showing poor healing (n = 7) 12 weeks after transplantation with meshed split-thickness skin grafts. The diagnostic value of matrix metalloproteinase-9 was good according to receiver-operating characteristic curve analysis. Matrix metalloproteinase activity in wound fluids from split-thickness skin graft donor-site wounds increased as a function of time and healing, but was still lower than matrix metalloproteinase activity in venous leg ulcer wound fluids, which showed increased levels of most biomarkers except for matrix metalloproteinase-9 and matrix metalloproteinase-2. In conclusion, wound fluid matrix metalloproteinase-9 concentration is a potential predictive biomarker of split-thickness skin graft healing in venous leg ulcers.

[Venous ulcus cruris-Surgical treatment]

Venous ulcus cruris is usually a chronic disease and an extreme burden for patients and their families. An analysis based on a random statutory health insurance sample of the AOK Hessen/KV Hessen estimated the number of affected people to be 400,000 in Germany. A venous ulcus cruris is always caused by an underlying chronic venous insufficiency (CVI). A spontaneous healing of this chronic disease without treatment is not to be expected. The conservative treatment includes an adequate compression treatment and exudate management. Surgical treatment is based on three pillars: an open surgical or endovenous approach to resolve the pathological venous reflux, uIcer surgery and in rare cases the various procedures of fascia surgery as well as defect coverage by a combination of negative pressure wound therapy and skin transplantation.

Frostbite injury: an unknown risk when using nitrous oxide as a party drug

In recent years nitrous oxide has become a popular party drug. Large cylinders filled with nitrous oxide are used to fill balloons for recreational use. We present two patients with severe third-degree cold burns on their thighs after clamping a large cylinder between their legs while filling balloons. During filling, large amounts of nitrous oxide are inhaled, which causes the pain to be numbed. As nitrous oxide is discharged from the cylinder, the cylinder becomes ice cold. Due to direct contact with the icecold cylinder and numbness, third-degree frostbite wounds occur. In both cases presented, the burn wounds had to be debrided and treated with split-thickness skin transplants. Awareness is needed as at first presentation as the burns look superficial, but can rapidly develop into third-degree burn wounds. Close follow-up and aggressive treatment is necessary to prevent infections and to regain a good functional outcome of the affected limb.

Chronic wounds: Treatment consensus

The Wound Healing Foundation (WHF) recognised a need for an unbiased consensus on the best treatment of chronic wounds. A panel of 13 experts were invited to a virtual meeting which took place on 27 March 2021. The proceedings were organised in the sub-sections diagnosis, debridement, infection control, dressings, grafting, pain management, oxygen treatment, outcomes and future needs. Eighty percent or better concurrence among the panellists was considered a consensus. A large number of critical questions were discussed and agreed upon. Important takeaways included that wound care needs to be simplified to a point that it can be delivered by the patient or the patient's family. Another one was that telemonitoring, which has proved very useful during the COVID-19 pandemic, can help reduce the frequency of interventions by a visiting nurse or a wound care center. Defining patient expectations is critical to designing a successful treatment. Patient outcomes might include wound specific outcomes such as time to heal, wound size reduction, as well as improvement in quality of life. For those patients with expectations of healing, an aggressive approach to achieve that goal is recommended. When healing is not an expectation, such as in patients receiving palliative wound care, outcomes might include pain reduction, exudate management, odour management and/or other quality of life benefits to wound care.

An Anhydrous Sodium Chloride Skin Preservation Model for Studies on Keratinocytes Grafting into the Wounds

Background. Human skin is needed for covering large body areas lost by trauma. The shortcomings of contemporary methods of skin storage are limited preservation time and high immunogenicity if allogeneic. Methods. We investigated whether long-lasting skin preservation in anhydrous sodium chloride (NaCl) may be the source of keratinocytes (KCs) for transplantation. Dehydrated skin fragments were preserved for a time frame from 1 week to 12 months. Then, skin fragments were rehydrated, and KCs were isolated. The viability of KCs was assessed in viability/cytotoxicity test. NaCl-preserved KCs were cultured for 7 days and transplanted to the dorsum of SCID mice. Results. The morphology of NaCl-preserved KCs was unaltered. KCs from all epidermal layers could be identified. All grafts were accepted by the recipients. Transplanted KCs: synthesized keratins 10 and 16 expressed antigens specific for stem cells and transient-amplifying cells, and remained HLA-I-positive. Moreover, they expressed the proliferative marker PCNA. Cells isolated from transplants remained viable and produced enzymes. Conclusions. Transplantation of KCs obtained from human skin and stored in anhydrous NaCl may be considered for the closure of extensive skin wounds. The originality of this method consists of an effective storage procedure and easy preparation of keratinocytes for transplantation.

Risk Factors for Loss to Follow-Up in the Lower Extremity Limb Salvage Population

BACKGROUND

Limb salvage for chronic lower extremity wounds requires long-term care best delivered by specialized multidisciplinary centers. This optimizes function, reduces amputation rates, and improves mortality. These centers may be limited to urban/academic settings, making access and appropriate follow-up challenging. Therefore, the authors hypothesize that both system- and patient-related factors put this population at exceedingly high risk for loss to follow-up.

METHODS

Records were reviewed retrospectively for 200 new patients seen at the Georgetown Center for Wound Healing in 2013. The primary outcome was loss to follow-up, defined as three consecutive missed appointments despite explicit documentation indicating the need for return visits. Demographic, clinical, and geographic data were compared. Multivariate logistic regression analysis for loss to follow-up status controlled for variables found significant in the bivariate analysis. Spatial dependency was evaluated using variograms.

RESULTS

Over a 6.5-year-period, 49.5 percent of patients followed were lost to follow-up. Male sex and increased driving distance to the limb salvage center were risk factors for loss to follow-up. Wound-specific characteristics including ankle and knee/thigh location were also associated with higher rates of loss to follow-up. There was no spatial dependency or discrete clustering of at-risk patients.

CONCLUSIONS

This study is the first of its kind to investigate the demographic and clinical characteristics that predispose chronic lower extremity wound patients to loss to follow-up. These findings inform stakeholders of the high rates of loss to follow-up and support decentralized specialty care, in the form of telemedicine, satellite facilities, and/or dedicated case managers. Future work will focus on targeting vulnerable populations through focused interventions to reduce patient and system burden.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Review of the Latest Methods of Epidermolysis Bullosa and Other Chronic Wounds Treatment Including BIOOPA Dressing

Epidermolysis bullosa (EB) is a hereditary genetic skin disorder, classified as a type of genodermatosis, which causes severe, chronic skin blisters associated with painful and potentially life-threatening complications. Currently, there is no effective therapy or cure for EB. However, over the past decade, there have been several important advances in treatment methods, which are now approaching clinical application, including gene therapy, protein replacement therapy, cell therapy (allogeneic fibroblasts, mesenchymal stromal cells), bone marrow stem cell transplant, culture/vaccination of revertant mosaic keratinocytes, gene editing/engineering, and the clinical application of inducible pluripotent stem cells. Tissue engineering scientists are developing materials that mimic the structure and natural healing process to promote skin reconstruction in the event of an incurable injury. Although a cure for EB remains elusive, recent data from animal models and preliminary human clinical trials have raised the expectations of patients, clinicians, and researchers, where modifying the disease and improving patients’ quality of life are now considered attainable goals. In addition, the lessons learned from the treatment of EB may improve the treatment of other genetic diseases.

Effectiveness of different types of skin grafting for treating venous leg ulcers: A protocol for systematic review and network meta-analysis

BACKGROUND

Venous leg ulcers (VLUs) are the most common ulcer on the lower extremity, with 4% of patients over the age of 65 suffering from VLUs worldwide. As a recurrent, chronic, disabling disease, VLUs are associated with prolonged disability, substantial socioeconomic impact, and significant psychosocial morbidity. At present, Skin grating is one of the most effective treatments for non-healing ulcers. However, there are still no new studies based on the latest research and new research methods to evaluate and compare the effect of different types of skin grafts for treating venous leg ulcers. Therefore, a Bayesian network meta-analysis (NMA) will be conducted to systematically assess skin grafting efficacy for VLUs.

METHODS

We will include randomized controlled trials (RCTs) involving patients with VLUs treated by skin grafts. Electronic databases and clinical trials registries will be searched from their inception until June 2021, without language or publication restrictions on status. The search strategy mainly includes Medical Subject Headings (MeSH) and free-text terms. Two review authors will independently perform data extraction and assessment of study quality. And We will use Bayesian NMA to evaluate all available evidence in STATA 14.0 and WinBUGS software.

RESULTS

This protocol will use Bayesian NMA to assess the effectiveness of different types of skin grafting for treating venous leg ulcers.

CONCLUSION

This study aims to synthesize the available evidence from RCTs in a network meta-analysis to summarize the best research available and provide consistency among treatment protocols given to patients, resulting in improved efficacy and the quality of care and reduced cost.

Incorporating a structural extracellular matrix gradient into a porcine urinary bladder matrix-based hydrogel dermal scaffold

The increasing prevalence of chronic, nonhealing wounds necessitates the investigation of full-thickness skin substitutes conducive to host integration and wound closure. Extracellular matrix (ECM)-based hydrogel scaffolds mimic the physiological matrix environment of dermal cells, thereby conferring favorable cellular adhesion, infiltration, and proliferation. However, low-concentration ECM hydrogels rapidly lose mechanical strength as they degrade, leaving them susceptible to shrinkage from fibroblast-mediated contraction. Conversely, high-concentration ECM hydrogels are typically too dense to permit nutrient diffusion and cellular migration. This study investigates the design and fabrication of a graded-concentration hydrogel composed of porcine urinary bladder matrix (UBM) as a dermal scaffold for potential use in chronic wound treatment. Our method of UBM isolation and decellularization effectively removed native DNA while preserving matrix proteins. Hydrogels composed of a range of decellularized UBM (dUBM) concentrations were characterized and used to design a three-tiered gradient hydrogel that promoted cellular activity and maintained structural integrity. The gradient dUBM hydrogel showed stability of cross-sectional area during collagenase degradation, despite considerable loss of mass. The gradient dUBM hydrogel also resisted fibroblast-mediated contraction while supporting high surface cell viability, demonstrating the mechanical support provided by denser layers of dUBM. Overall, incorporation of an ECM concentration gradient into a porcine UBM-based hydrogel scaffold capitalizes on the unique advantages of both high and low-concentration ECM hydrogels, and mitigates the structural weaknesses that have limited the efficacy of hydrogel dermal scaffolds for chronic wounds. Our gradient design shows promise for future development of stable, pro-regenerative wound scaffolds with customized architectures using 3D printing.

Study protocol for a multicentre, randomised controlled trial to compare the use of the decellularised dermis allograft in addition to standard care versus standard care alone for the treatment of venous leg ulceration: DAVE trial

INTRODUCTION

Venous leg ulceration (VLU), the most common type of chronic ulcer, can be difficult to heal and is a major cause of morbidity and reduced quality of life. Although compression bandaging is the principal treatment, it is time-consuming and bandage application requires specific training. There is evidence that intervention on superficial venous incompetence can help ulcer healing and recurrence, but this is not accessible to all patients. Hence, new treatments are required to address these chronic wounds. One possible adjuvant treatment for VLU is human decellularised dermis (DCD), a type of skin graft derived from skin from deceased tissue donors. Although DCD has the potential to promote ulcer healing, there is a paucity of data for its use in patients with VLU.

METHODS AND ANALYSIS

This is a multicentre, parallel group, pragmatic randomised controlled trial. One hundred and ninety-six patients with VLU will be randomly assigned to receive either the DCD allograft in addition to standard care or standard care alone. The primary outcome is the proportion of participants with a healed index ulcer at 12 weeks post-randomisation in each treatment arm. Secondary outcomes include the time to index ulcer healing and the proportion of participants with a healed index ulcer at 12 months. Changes in quality of life scores and cost-effectiveness will also be assessed. All analyses will be carried out on an intention-to-treat (ITT) basis. A mixed-effects, logistic regression on the outcome of the proportion of those with the index ulcer healed at 12 weeks will be performed. Secondary outcomes will be assessed using various statistical models appropriate to the distribution and nature of these outcomes.

ETHICS AND DISSEMINATION

Ethical approval was granted by the Bloomsbury Research Ethics Committee (19/LO/1271). Findings will be published in a peer-reviewed journal and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

ISRCTN21541209.

Tibial cortex transverse transport facilitating healing in patients with recalcitrant non-diabetic leg ulcers

OBJECTIVE

The treatment of recalcitrant not-diabetic leg ulcers remains challenging. Distraction osteogenesis is accompanying by angiogenesis and neovascularization in the surrounding tissues. We previously applied tibial cortex transverse transport (TTT) to patients with recalcitrant diabetic foot ulcers and found neovascularization and increased perfusion in the foot and consequently enhanced healing and limb salvage and reduced recurrence. However, the effects of TTT on recalcitrant non-diabetic leg ulcer remains largely unknown.

METHODS

Consecutive patients (n ​= ​85) with recalcitrant non-diabetic leg ulcers (University of Texas Grade 2-B to 3-D, ie, wound penetrating to the tendon, capsule, bone, or joint with infection and/or ischemia) were recruited and divided into TTT (n ​= ​42) and control (n ​= ​43) groups based on the treatment they received. There were 36 (85.7%) arterial ulcers, 4 (9.5%) venous ulcers and 2 (4.8%) mixed ulcers in the TTT group and 32 (74.4%) arterial ulcers, 7 (16.7%) venous ulcers and 4 (9.3%) mixed ulcers in the control group (p ​> ​0.05). The two groups were matched on demographic and clinical characteristics. Patients in the TTT group underwent tibial corticotomy followed by 4 weeks of distraction medially then laterally, while those in the control group received conventional surgeries (debridements, revascularization, reconstruction with flaps, or skin grafts or equivalents). Ulcer healing and healing time, limb salvage, recurrence, and patient death were evaluated at a 1-year follow-up. Changes in leg small vessels were assessed in the TTT group using computed tomography angiography (CTA).

RESULTS

TTT group had higher healing rates at 1-year follow-up than the control group (78.6% [33/42] vs. 58.1% [25/43], OR 2.64 [95% CI 1.10 to 6.85], p ​= ​0.04). The healing time of the TTT group was shorter than the control group (4.5 vs. 6.1 months, mean difference -1.60 [95% CI -2.93 to -0.26], p ​= ​0.02). There were no significant differences in rates of major amputation, reulceration, or mortality between the groups (p ​> ​0.05). TTT group displayed more small vessels 4 weeks postoperatively at the wound area, the foot, and the calf of the ipsilateral side in CTA. All patients in the TTT group achieved good union at the osteotomy site and had no skin or soft tissue necrosis or infection around the incision area.

CONCLUSION

The findings showed that TTT facilitated the healing of recalcitrant non-diabetic leg ulcers and reduced the healing time compared with conventional surgeries. They suggest that TTT is an effective procedure to treat recalcitrant non-diabetic foot ulcers compared with standard surgical therapy. The procedure of TTT is relatively simple. Randomized controlled trials are required to confirm these findings.

THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE

TTT can be used as an effective treatment for recalcitrant non-diabetic leg ulcers in patients. The mechanism may be associated with the neovascularization in the ulcerated foot induced by TTT and consequently increased perfusion. Together with previous findings from recalcitrant diabetic leg ulcers, the findings suggest TTT as an effective procedure to treat recalcitrant chronic leg ulcers.

[Surgical treatment for chronic leg ulcer]

Leg ulcers pose a therapeutic challenge due to a chronic healing process. Conservative wound dressings are initially the treatment of choice, but their effectiveness in therapy-refractory wounds is limited. In these cases, multiple mechanical debridement in combination with split-thickness skin grafts (STSG) are a simple and safe treatment option for ulcer coverage. Additional therapy with negative pressure wound therapy (NPWT) improves the surgical outcome by promoting ulcer granulation, continuous elimination of exsudate and blood as well as increased contact pressure on the skin graft. After transplantation, the split skin graft requires daily wound dressings until it has fully healed after approximately 3 weeks.

A multistage combined approach to promote diabetic wound healing in COVID-19 era

When diabetes mellitus is not properly controlled with drugs and a healthy lifestyle, it exposes patients with advanced peripheral arterial disease or critical limb ischaemia (CLI) to the most serious complications, in particular lower limb ulcers. Surgical or endovascular treatments represent the first line of intervention; in addition, the adequate management of ulcers can guarantee not only a faster wound healing but also the improvement of the patient's prognosis. To speed up this process, negative pressure wound therapy (NPWT), platelet-rich plasma (PRP), and other advanced moist wound dressing have been proposed. During Coronavirus disease 2019 (COVID-19) pandemic, many patients with CLI and diabetes mellitus had difficult access to advanced treatments with a significant reduction in life expectancy. We report the cases of patients with non-healing ulcers and CLI treated with an empiric multistage approach after successful endovascular revascularisation; the postoperative course was eventful in all patients, and foot ulcers are currently in an advanced state of healing. The association between adequate revascularisation, systemic anti-inflammatory, and antibiotic therapy with the multistage advanced medications ensures healing of ulcers, limb salvage, and improvement of patient prognosis.

Combination product of dermal matrix, human mesenchymal stem cells, and timolol promotes diabetic wound healing in mice

Diabetic foot ulcers are a major health care concern with limited effective therapies. Mesenchymal stem cell (MSC)-based therapies are promising treatment options due to their beneficial effects of immunomodulation, angiogenesis, and other paracrine effects. We investigated whether a bioengineered scaffold device containing hypoxia-preconditioned, allogeneic human MSCs combined with the beta-adrenergic antagonist timolol could improve impaired wound healing in diabetic mice. Different iterations were tested to optimize the primary wound outcome, which was percent of wound epithelialization. MSC preconditioned in 1 μM timolol at 1% oxygen (hypoxia) seeded at a density of 2.5 × 10⁵  cells/cm² on Integra Matrix Wound Scaffold (MSC/T/H/S) applied to wounds and combined with daily topical timolol applications at 2.9 mM resulted in optimal wound epithelialization 65.6% (24.9% ± 13.0% with MSC/T/H/S vs 41.2% ± 20.1%, in control). Systemic absorption of timolol was below the HPLC limit of quantification, suggesting that with the 7-day treatment, accumulative steady-state timolol concentration is minimal. In the early inflammation stage of healing, the MSC/T/H/S treatment increased CCL2 expression, lowered the pro-inflammatory cytokines IL-1B and IL6 levels, decreased neutrophils by 44.8%, and shifted the macrophage ratio of M2/M1 to 1.9 in the wound, demonstrating an anti-inflammatory benefit. Importantly, expression of the endothelial marker CD31 was increased by 2.5-fold with this treatment. Overall, the combination device successfully improved wound healing and reduced the wound inflammatory response in the diabetic mouse model, suggesting that it could be translated to a therapy for patients with diabetic chronic wounds.

Comparing hospital stay and patient satisfaction in a resource poor setting using conventional and locally adapted negative pressure wound dressing methods in management of leg ulcers with split skin grafts: a comparative prospective study

Introduction

chronic leg ulcers cause a prolonged hospital stay with devastating effects on the patients. Several modifiable factors are taken care of to reduce the duration of stay. A further measure to hasten wound bed preparation pre-grafting and to hasten graft healing post-grafting is with negative pressure dressing.

Methods

sixty-two patients were placed in two groups of 31 cases each. The wound beds were prepared with negative pressure apparatus locally adapted with suction machine for group A and with conventional gauze dressing using 5% povidone iodine soaks for group B. Grafted wound was also dressed similarly for the respective groups. Grafts were inspected on the 5^th post-operative day and were determined with planimeter grid. Grafts were monitored until completely healed and patients were discharged. Satisfaction and length of stay were determined at discharge.

Results

the mean hospital stay pre-grafting and post-grafting were 12.2 (±8.64) days and 13.6 (±2.03) days respectively for the negative pressure dressing and 28.8 (±30.9) days and 21.8 (±21.97) days respectively for the traditional dressing group. These differences with p values of 0.038 for the pre-grafting stay and 0.006 for the post-grafting stay were statistically significant. The patients managed with negative pressure dressing also recorded greater satisfaction with the process and the outcome.

Conclusion

negative pressure dressing contributes significantly to reducing the length of hospital stay in chronic leg ulcers both in wound bed preparation and in graft healing resulting to better patient satisfaction than in patients treated with conventional gauze dressing and 5% povidone iodine soaks.

PG-TIME: A practical approach to the clinical management of pyoderma gangrenosum

Pyoderma gangrenosum (PG) is a neutrophilic dermatosis which may be rapidly progressive. Standard guidelines for local treatment are lacking. Through our experience, we suggested a local treatment algorithm based on the tissue, infection, moisture balance, and epithelization (TIME) concept. The clinical and histopathological features of 52 patients with PG, the duration, and the evolution of the lesions were retrospectively evaluated. Systemic therapies, local treatments, and standard wound treatments were reported. We observed ulcerative PG in the majority of the patients (82.6%), followed by the pustular form (9.6%), the peristomal type (3.8%), the vegetative form (1.9%), and the bullous type (1.9%). The lower leg was the most commonly area affected (90.4% of cases). Pathergy was reported in 15.3% of cases. The first-line treatment was the use of oral glucocorticosteroids (GCSs). We observed healing after 3 weeks of GCS in 17.3% of cases. In 25% of all cases, we obtained complete healing with long-term low doses (<0.5 mg/kg) of GCS in the range of 2 to 6 months. We used second-line treatments in 57.6% of patients. Local, systemic treatment, and correct wound management can be associated with better clinical results. We suggest a new local therapeutic algorithm in both the inflammatory and noninflammatory healing phases.

Polyplexes System to Enhance the LL-37 Antimicrobial Peptide Expression in Human Skin Cells

Inefficient autologous tissue recovery in diverse skin injuries increases the susceptibility of patients to infections caused by multiresistant microorganisms, resulting in a high mortality rate. Nonviral transfection is an attractive alternative for these patients, where genetically modified cells incorporated into skin substitutes could release additional antimicrobial agents into the native skin. In this work, we have modulated the conditions of using a nonviral system for transfection of primary human keratinocytes and fibroblasts, consisting of a polymer/plasmid DNA (pDNA) complex called polyplex and its effects on the expression of LL-37 antimicrobial peptide. Linear and branched polyethylenimine (PEI) polymers in different weight concentrations were varied for evaluating the formation and colloidal characteristics of the polyplexes. The PEI/pDNA polyplexes with 19 nitrogen/phosphate ratio are nanometric particles (400 and 250 nm with linear and branched PEI, respectively) exhibiting positive surface (+30 ± 2 mV). Both kinds of polyplexes allowed the expression of a reporter gene and increased the human cathelicidin antimicrobial peptide gene expression in transfected keratinocytes and fibroblasts; however, greater cytotoxicity was observed when polyplexes formed with branched PEI were used. Moreover, cell culture supernatants from transfected cells with linear PEI/pDNA polyplexes showed enhanced antimicrobial activity (decrease of bacterial growth in 95.8%) against a Staphylococcus aureus strain in vitro. The study of the PEI/pDNA polyplexes formation allowed us to develop an improved transfection strategy of skin cells, promoting the production of LL-37 antimicrobial peptide. In the future, this strategy could be used for the construction of skin substitutes to prevent, reduce, or eliminate bacterial infections. Impact statement The results of this study contribute to the understanding of the polyplexes system in the genetic modification of skin cells and its effects on the expression of the LL-37 antimicrobial peptide. In the future, three-dimensional skin substitutes built with these cells could be an efficient way to decrease bacterial growth and prevent the infections in skin wounds.

Global guidelines trends and controversies in lower limb venous and lymphatic disease: Narrative literature revision and experts' opinions following the vWINter international meeting in Phlebology, Lymphology & Aesthetics, 23-25 January 2019

Guidelines are fundamental in addressing everyday clinical indications and in reporting the current evidence-based data of related scientific investigations. At the same time, a spatial and temporal issue can limit their value. Indeed, variability in the recommendations can be found both among the same nation different scientific societies and among different nations/continents. On the other side, Garcia already published in 2014 data showing how, after three years in average, one out of five recommendations gets outdated (Martinez Garcia LM, Sanabria AJ, Garcia Alvarez E, et al. The validity of recommendations from clinical guidelines: a survival analysis. CMAJ 2014;186(16):1211–1219). The present document reports a narrative literature revision on the major international recommendations in lower limb venous and lymphatic disease management, focusing on the different countries’ guidelines, trends and controversies from all the continents, while identifying new evidence-based data potentially influencing future guidelines. World renowned experts’ opinions are also provided. The document has been written following the recorded round tables scientific discussions held at the vWINter international meeting (22–26 January 2019; Cortina d’Ampezzo, Italy) and the pre- and post-meeting literature search performed by the leading experts.

Fabrication of centimeter-scale and geometrically arbitrary vascular networks using in vitro self-assembly

One of the largest challenges facing the field of tissue engineering is the incorporation of a functional vasculature, allowing effective nourishment of graft tissue beyond diffusion length scales. Here, we demonstrate a methodology for inducing the robust self-assembly of endothelial cells into stable three-dimensional perfusable networks on millimeter and centimeter length scales. Utilizing broadly accessible cell strains and reagents, we have rigorously tested a state space of cell densities (0.5-2.0 × 10⁶ cell/mL) and collagen gel densities (2-6 mg/mL) that result in robust vascular network formation. Further, over the range of culture conditions with which we observed robust network formation, we advanced image processing algorithms and quantitative metrics to assess network connectivity, coverage, tortuosity, lumenization, and vessel diameter. These data demonstrate that decreasing collagen density produced more connected networks with higher coverage. Finally, we demonstrated that this methodology results in the formation of perfusable networks, is extensible to arbitrary geometries and centimeter scales, and results in networks that remain stable for 21 days without the need for the co-culture of supporting cells. Given the robustness and accessibility, this system is ideal for studies of tissue-scale biology, as well as future studies on the formation and remodeling of larger engineered graft tissues.

Specialized Living Wound Dressing Based on the Self-Assembly Approach of Tissue Engineering

There is a high incidence of failure and recurrence for chronic skin wounds following conventional therapies. To promote healing, the use of skin substitutes containing living cells as wound dressings has been proposed. The aim of this study was to produce a scaffold-free cell-based bilayered tissue-engineered skin substitute (TES) containing living fibroblasts and keratinocytes suitable for use as wound dressing, while considering production time, handling effort during the manufacturing process, and stability of the final product. The self-assembly method, which relies on the ability of mesenchymal cells to secrete and organize connective tissue sheet sustaining keratinocyte growth, was used to produce TESs. Three fibroblast-seeding densities were tested to produce tissue sheets. At day 17, keratinocytes were added onto 1 or 3 (reference method) stacked tissue sheets. Four days later, TESs were subjected either to 4, 10, or 17 days of culture at the air–liquid interface (A/L). All resulting TESs were comparable in terms of their histological aspect, protein expression profile and contractile behavior in vitro. However, signs of extracellular matrix (ECM) digestion that progressed over culture time were noted in TESs produced with only one fibroblast-derived tissue sheet. With lower fibroblast density, the ECM of TESs was almost completely digested after 10 days A/L and lost histological integrity after grafting in athymic mice. Increasing the fibroblast seeding density 5 to 10 times solved this problem. We conclude that the proposed method allows for a 25-day production of a living TES, which retains its histological characteristics in vitro for at least two weeks.

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.

Health-related quality of life and patient burden in patients with split-thickness skin graft donor site wounds

Split-thickness skin grafting is a common procedure to treat different kinds of wounds. This systematic, multicentre, observational, cross-sectional study of adult patients with split-thickness skin graft (STSG) donor site wounds was conducted to evaluate quality of life (QoL) impairments caused by donor site wounds following split-thickness skin grafting. Therefore, 112 patients from 12 wound centres in Germany were examined based on patient and physician questionnaires as well as a physical examination of the donor site wound. Most indications for skin grafting were postsurgical treatment (n = 51; 42.5%) and chronic wounds (n = 47; 39.2%). European QoL visual analoque scale (EQ VAS) averaged 64.7 ± 23.3, European QoL 5 dimensions (EQ-5D) averaged 77.4 ± 30.0. Wound-QoL (range: 0-4) was rated 0.8 ± 0.8 post-surgery and 0.4 ± 0.6 at the time of survey (on average 21 weeks between the time points). Compared to averaged Wound-QoL scores of chronic wounds donor site-related QoL impairments in split-thickness skin-graft patients were less pronounced. There were significant differences in patient burden immediately after surgery compared to the time of the survey, with medium effect sizes. This supports the hypothesis that faster healing of the donor site wound leads to more favourable patient-reported outcomes.

Escleroterapia de safena associada a enxerto de pele no tratamento de úlceras venosas

Contexto

Úlceras são a resultante final de varizes associadas a refluxo de veias safenas.

Objetivo

Demonstrar a possibilidade de associar dois procedimentos, a escleroterapia com espuma de veias safenas e o enxerto de pele parcial, para o tratamento de pacientes com úlceras venosas relacionadas a refluxo de veias safenas.

Métodos

Foram tratados 20 membros em 20 pacientes, todos com ulcerações relacionadas a refluxo de veias safenas. Realizamos o enxerto de pele expandida, seguido da escleroterapia ecoguiada com espuma de polidocanol nas veias associadas às úlceras, através de punção ou dissecção da veia.

Resultados

Em todos os casos, houve melhora dos sintomas relacionados à úlcera e cicatrização da lesão. Em 11 casos, obtivemos a viabilidade do enxerto de pele por completo; em quatro casos, houve cicatrização de cerca de 50% da lesão; e nos cinco casos restantes, houve cicatrização de aproximadamente 75% da lesão. A primeira ultrassonografia de controle revelou esclerose completa dos vasos tratados em 19 dos 20 casos e esclerose parcial sem refluxo detectável em um caso. Na segunda ultrassonografia, realizada após 45 dias, observamos esclerose completa de 15 casos; em cinco casos, houve esclerose parcial, dos quais três sem refluxo detectável e dois com refluxo em segmentos isolados associados a varizes. A complicação mais frequente foi a pigmentação nos trajetos venosos, observada em 13 pacientes. Um caso apresentou trombose assintomática de veias musculares da perna.

Conclusão

Essa associação de procedimentos consiste em uma opção válida com potencial para promover um tratamento mais breve e de menor custo.

Effectiveness of collagen/oxidised regenerated cellulose/silver-containing composite wound dressing for the treatment of medium-depth split-thickness skin graft donor site wounds in multi-morbid patients: a prospective, non-comparative, single-centre study

Split-thickness skin grafting (STSG) is a widely used method in reconstructive surgery, but donor site wounds (DSWs) are often slow healing and painful. This prospective study evaluated the performance of a composite wound dressing containing collagen/oxidised regenerated cellulose in the treatment of medium-depth (0·4 mm) DSWs in 25 multi-morbid patients with chronic leg ulcers requiring STSG. The range of patients' ages was 44-84 years (mean 71·6 years) with DSW sizes ranging between 12 and 162 cm2 (mean 78 cm2 ). Comorbidities included anticoagulation therapy (15 patients), anaemia (11 patients), diabetes (6 patients) and methicillin-resistant Staphylococcus aureus (MRSA) ulcer colonisation (6 patients). The first dressing change was performed after 10 days. Complete reepithelialisation was observed between the 10th and 34th day (mean 17·2, median 14 days). Postoperative medium to strong bleeding occurred in only five patients (four with anticoagulation). Wound pain levels one day after harvesting were only moderate (range 0-1·5, mean 0·5, median 0·5 on a six-item scale). No wound infection was observed during the first dressing. The composite dressing used allowed for the fast healing of medium-depth DSWs with minimal or no postoperative pain and bleeding in older multi-morbid patients under anticoagulation treatment.

Therapy of ulcus cruris of venous and mixed venous arterial origin with autologous, adult, native progenitor cells from subcutaneous adipose tissue: a prospective clinical pilot study

BACKGROUND

The stromal vascular fraction (SVF) of adipose tissue consists of cellular subpopulations with distinct regenerative potential.

OBJECTIVE

To investigate the regenerative capacities of autologous SVF cells in the treatment of chronic leg ulcers of venous (VLU) and arterial-venous (AVLU) origin.

METHODS

Multimorbid ulcer patients received a singular topical treatment with 9-15 × 10⁶ SVF cells, separated from abdominal lipoaspirates by digestion with collagenase and neutral protease and applied immediately after isolation. The primary endpoints were the change in wound size 12 weeks after treatment and evaluation of adverse events. Secondary endpoints included the time to complete wound epithelialization and change in pain levels. Postoperative wound treatment modalities and treatment of comorbidities were not intensified compared with pre-operative management. Follow-up period was at least 6 months.

RESULTS

Sixteen elderly ulcer patients (seven with VLU, nine with AVLU) were treated as described. All VLU patients (median ulcer size: 48.25 cm² ) and four of nine AVLU patients showed complete epithelialization of the ulcers within 71-174 days. In three patients with large ulcerations on both legs, ulcerations on the non-treated, contralateral leg also epithelialized. Patients reported a considerable rapid decrease in pain intensity by 2.5 points on average on a visual scale from 1 to 5 within the first 2 weeks after treatment. The patients were followed up for 9-44 months (median: 30 months). No severe side-effects were observed.

CONCLUSIONS

The use of SVF cells presents an effective, minimally invasive option for the treatment of VLU and AVLU even in multimorbid patients. In patients with larger predominantly ischaemic AVLU and comorbidities, one-time application of the used amounts of SVF cells was not sufficient in the majority of cases.

Treatment of standardised wounds with pure epidermal micrografts generated with an automated device

In this study, we analysed the effects of pure epidermal micrografts generated with an automated device in a standardised human wound model. Epidermal micrografts were harvested using an automated device. Micrografts were then transplanted onto split-skin donor sites. The target area was only partially covered with transplants to create an intra-individual control area. Wounds were evaluated by subjective assessment as well as measurements with combined laser and white light spectroscopy and cutometry. The epidermal graft sites remained completely stable, whereas control sites offered partially unstable and blistering areas. Statistically, no measurable difference in the speed of initial reepithelialisation could be shown. However, there was an increased pliability and softness of the treated areas that correlated with the subjective impression of both investigators and patients. There was a significantly higher relative haemoglobin concentration, measurable in treated and untreated areas at 4 weeks and 6 months. Cutometry showed no differences in skin properties between treated and untreated areas. This study shows an effect of epidermal micrografts in a standardised human wound model and supports the positive impact of keratinocytes on early wound healing as described in literature. Long-term effects of epidermal grafting deserve further studies.

A Text-Mining Framework for Supporting Systematic Reviews

Systematic reviews (SRs) involve the identification, appraisal, and synthesis of all relevant studies for focused questions in a structured reproducible manner. High-quality SRs follow strict procedures and require significant resources and time. We investigated advanced text-mining approaches to reduce the burden associated with abstract screening in SRs and provide high-level information summary. A text-mining SR supporting framework consisting of three self-defined semantics-based ranking metrics was proposed, including keyword relevance, indexed-term relevance and topic relevance. Keyword relevance is based on the user-defined keyword list used in the search strategy. Indexed-term relevance is derived from indexed vocabulary developed by domain experts used for indexing journal articles and books. Topic relevance is defined as the semantic similarity among retrieved abstracts in terms of topics generated by latent Dirichlet allocation, a Bayesian-based model for discovering topics. We tested the proposed framework using three published SRs addressing a variety of topics (Mass Media Interventions, Rectal Cancer and Influenza Vaccine). The results showed that when 91.8%, 85.7%, and 49.3% of the abstract screening labor was saved, the recalls were as high as 100% for the three cases; respectively. Relevant studies identified manually showed strong topic similarity through topic analysis, which supported the inclusion of topic analysis as relevance metric. It was demonstrated that advanced text mining approaches can significantly reduce the abstract screening labor of SRs and provide an informative summary of relevant studies.