Experience with NovoSorb® Biodegradable Temporising Matrix in reconstruction of complex wounds

Strategic Use of Biodegradable Temporizing Matrix (BTM) in Wound Healing: A Case Series in Asian Patients

Skin and soft tissue reconstruction has long been based on the reconstructive ladder. However, a skin substitute has become popular due to its predictable outcomes, without donor-site morbidity. The biodegradable temporizing matrix (BTM; NovoSorb, PolyNovo Ltd., Port Melbourne, Australia) is a synthetic skin substitute that has recently gained its clinical application. Compared with those of other dermal templates, the clinical efficacy and performance of the BTM are not well established, especially among the Asian population. This study aims to share our experience and strategy of using BTM in various wound conditions. The data of patients who underwent skin and soft tissue reconstruction with BTM at a single institution between January 2022 and December 2023 were reviewed. The patient demographics, wound characteristics, surgical details, secondary procedures, and complications were recorded and analyzed. Postoperative 6-month photographs were collected and independently evaluated by two plastic surgeons and two wound care center nurses using the Manchester Scar Scale (MSS). This study included 37 patients, consisting of 22 males and 15 females with a mean age of 51.8 years (range, 18-86 years old). The wound etiologies included trauma (67.6%), necrotizing soft tissue infection (16.2%), burns (10.8%), toe gangrene (2.7%), and scar excision (2.7%). The average wound area covered by BTM was 50.6 ± 47.6 cm2. Among the patients, eight received concomitant flap surgery and BTM implantation, 20 (54.1%) underwent subsequent split-thickness skin grafts (STSG), and 17 had small wounds (mean: 21.6 cm2) healed by secondary intention. Infection was the most common complication, affecting six patients (n = 6 [16.2%]), five of whom were treated conservatively, and only one required debridement. Thirty-three patients (89.2%) had good BTM take, and only four had BTM failure, requiring further reconstruction. At the last follow-up, 35 out of the 37 patients (94.6%) achieved successful wound closure, and the total MSS score was 10.44 ± 2.94, indicating a satisfactory scar condition. The patients who underwent BTM grafting without STSG had better scar scores than those who received STSG (8.71 ± 2.60 vs. 11.18 ± 2.84, p = 0.039). In conclusion, the BTM is effective and feasible in treating various wounds, with relatively low complication rates, and it can thus be considered as an alternative for skin and soft tissue reconstruction. When combined with adipofasical flap reconstruction, it achieves a more comprehensive anatomical restoration.

NovoSorb® Biodegradable Temporising Matrix (BTM): What we learned from the first 300 consecutive cases

INTRODUCTION

Extensive full-thickness soft-tissue defects remain a challenge in reconstructive surgery. NovoSorb® Biodegradable Temporising Matrix (BTM) represents a novel dermal substitute and was evaluated in wounds deriving from different aetiologies and to highlight risk factors for poor take rates.

METHODS

All patients treated with BTM at our department between March 2020 and October 2022 were included. Differences in univariate and linear regression models identified predictors and risk factors for take rates of BTM and split-thickness skin grafts (STSG).

RESULTS

Three hundred patients (mean age 54.2 ± 20.1 years, 66.3% male, 59.7% burns, 19.7% trauma and 20.6% others) were evaluated. Mean take rates of BTM and STSG after BTM delamination were 82.7 ± 25.2% and 86.0 ± 22.6%, respectively. Multiple regression analyses showed that higher body mass index (BMI, OR 0.43, 95% CI 0.86, -0.01, p = 0.44), prior allograft transplantation (OR 15.12, 95% CI 26.98, -3.31, p = 0.041), longer trauma-to-BTM-application intervals (OR 0.01, 95% CI 0.001, -0.001, p = 0.038), positive wound swabs before BTM (OR 7.15, 95% CI 13.50, -0.80, p = 0.028) and peripheral artery disease (OR 10.80, 95% CI 18.63, -2.96, p = 0.007) were associated with poorer BTM take. Higher BMI (OR 0.40, 95% CI 0.76, -0.08, p = 0.026), increasing BTM graft surface areas (OR 0.58, 95% CI -1.00, -0.17, p = 0.005), prior allograft (OR 12.20, 95% CI -21.99, -2.41, p = 0.015) or autograft transplantations (OR 22.42, 95% CI 38.69, -6.14, p = 0.001), tumour as the aetiology of the wound (OR 37.42, 95% CI 57.41, -17.83, p = 0.001), diabetes (OR 6.64, 95% CI 12.80, -0.48, p = 0.035) and impaired kidney function (OR 5.90, 95% CI 10.94, -0.86, p = 0.021) were associated with poorer STSG take after delamination of BTM, whereas higher BTM take rates were associated with better STSG take (OR 0.40, 95% CI 0.31,0.50, p < 0.001).

CONCLUSION

Extensive complex wounds of different aetiologies unsuitable for immediate STSG can be successfully reconstructed by means of two-staged BTM application and subsequent skin grafting. Importantly, presence of wound contamination or infection and prior allograft coverage appear to jeopardise good BTM and STSG take.

The Application of a Synthetic Biodegradable Temporizing Matrix in Extensive Burn Injury: A Unicenter Experience of 175 Cases

Objectives: Addressing extensive and deep burn wounds poses considerable challenges for both patients and surgeons. The NovoSorb® Biodegradable Temporizing Matrix (BTM) emerged as a novel dermal substitute and has been subjected to evaluation in large burn wound cases, with a specific focus on identifying risk factors associated with suboptimal take rates. Methods: All patients with burn wounds greater than 10% body surface that underwent BTM treatment between March 2020 and November 2023 were eligible for inclusion. Univariate analyses and linear regression models were employed to discern risk factors and predictors influencing the take rates of both the BTM and split-thickness skin grafts (STSGs). Results: A total of 175 patients (mean age 56.2 ± 19.8 years, 70.3% male) were evaluated. The mean take rates of the BTM and STSGs were 82.0 ± 24.7% and 87.3 ± 19.0%, respectively. There were significant negative correlations between BTM take and the number of surgeries before BTM application (r = -0.19, p = 0.01), %TBSA and STSG take (r = -0.36, p = <0.001) and significant positive correlations between BTM and STSG take (r = 0.41, p ≤ 0.001) in addition to NPWT and STSG take (r = 0.21, p = 0.01). Multivariate regression analyses showed that a larger number of surgeries prior to BTM application (OR -3.41, 95% CI -6.82, -0.03, p = 0.04) was associated with poorer BTM take. Allograft treatment before BTM application (OR -14.7, 95% CI -23.0, -6.43,p = 0.01) and failed treatment with STSG before BTM application (OR -20.8, 95% CI -36.3, -5.23, p ≤ 0.01) were associated with poorer STSG take, whereas higher BTM take rates were associated with overall higher STSG take (OR -0.15, 95% 0.05, 0.26, p = 0.01). The Meek technique was used in 24 patients and showed similar take rates (BTM: 76.3 ± 28.0%, p = 0.22; STSG: 80.7 ± 21.1, p = 0.07). Conclusions: This study summarizes our findings on the application of a BTM in the context of large burn wounds. The results demonstrate that successful treatment can be achieved even in patients with extensive burns, resulting in satisfying take rates for both the BTM and STSG. The data underscore the importance of promptly applying a BTM to debrided wounds and indicate good results when using Meek.

Use of the modified meek technique for the coverage of extensive burn wounds

INTRODUCTION

Autologous split thickness skin grafting using meshing technique remains the preferred option for the management of deep dermal and full thickness burns. The limited donor site availability seen in patients with extensive burns, however, restricts use of the mesh grafting technique for skin expansion. Meek micrografting was developed to allow for greater expansion, and, therefore, more reliable treatment of extensive burns. This study aimed to present our outcomes using the Meek micrografting technique and identify risk factors for graft failure.

METHODS

A retrospective review of patients admitted to our large academic hospital who were treated with the Meek micrografting technique from 2013 to 2022 was conducted. Patient demographics, surgical characteristics and outcomes were reported. Regression analyses were performed to identify factors that influence graft take and reoperation rate.

RESULTS

A total of 73 patients with a mean age of 45.7 ± 19.9 years and mean burn size of 60.0 ± 17.8%TBSA, with 45.3 ± 14.9% TBSA being third degree burns, received Meek transplantation. The mean graft take after removal of the pre-folded polyamide gauze at the tenth post-operative day was 75.8 ± 14.7%. Pre-treatment with use of an allograft, longer waiting time between admission and Meek grafting and transplantation over a dermal matrix were identified as positive predictors for graft take, while age was established as a negative predictor.

CONCLUSION

By examining the outcomes of the Meek micrografting technique in extensive burn wounds we identified that preconditioning of the wound bed, through allograft or negative pressure wound therapy application, positively correlates with improved outcomes, including higher graft take. At the same time, older age was seen to negatively correlate with graft take. Overall, Meek transplantation displays a favorable safety profile with promising outcomes. Future prospective studies and clinical trials can optimize the procedure and help establish it as the golden standard for extensive and complex burns.

Application of pulsed electric field technology to skin engineering

Tissue engineering encompasses a range of techniques that direct the growth of cells into a living tissue construct for regenerative medicine applications, disease models, drug discovery, and safety testing. These techniques have been implemented to alleviate the clinical burdens of impaired healing of skin, bone, and other tissues. Construct development requires the integration of tissue-specific cells and/or an extracellular matrix-mimicking biomaterial for structural support. Production of such constructs is generally expensive and environmentally costly, thus eco-sustainable approaches should be explored. Pulsed electric field (PEF) technology is a nonthermal physical processing method commonly used in food production and biomedical applications. In this review, the key principles of PEF and the application of PEF technology for skin engineering will be discussed, with an emphasis on how PEF can be applied to skin cells to modify their behaviour, and to biomaterials to assist in their isolation or sterilisation, or to modify their physical properties. The findings indicate that the success of PEF in tissue engineering will be reliant on systematic evaluation of key parameters, such as electric field strength, and their impact on different skin cell and biomaterial types. Linking tangible input parameters to biological responses critical to healing will assist with the development of PEF as a sustainable tool for skin repair and other tissue engineering applications.

NovoSorb® biodegradable temporising matrix (BTM) in the reconstruction of cutaneous malignancies in a major cancer centre: a case series

BACKGROUND

Non-graftable or composite defect reconstruction represents a major challenge to the reconstructive surgeon, with many wounds requiring local flap or free microvascular tissue transfer approaches. The recent advent of synthetic skin substitutes such as Biodegradable Temporizing Matrix (BTM) have revolutionized the management of complex defects including those caused by burns, trauma and infection, with low-morbidity and low-complexity surgery. However, limited data exist supporting their use in cancer reconstruction in Australia.

METHODS

We performed a prospective cohort study of patients undergoing cancer resection and reconstruction with BTM between February 2021 and February 2023 in our institution. Reported outcomes included matrix integration, infection, and return to theatre.

RESULTS

Twelve patients underwent reconstruction of primary or secondary defects following cancer resection during this period. Eight patients were male, four female, mean age at surgery was 70 years. Pathology resected included squamous cell carcinoma (SCC) and melanoma of the head and neck, sarcoma resection of the lower limb, and osteoradionecrosis (ORN) of the scalp. T-stage of primary tumours ranged from T2 to T4 and one in-transit metastasis of melanoma. Four patients were treated with radiotherapy, two of whom received postoperative radiotherapy (PORT) and two who received neoadjuvant radiotherapy, three additional patients had an intervention to a previously irradiated wound bed for recurrence or ORN. Overall matrix integration was 83% (10/12), with a 50% integration rate (2/4) observed in the post-radiotherapy group, requiring return to theatre for alternative reconstructive approaches.

CONCLUSION

We report our experience with a synthetic dermal matrix (BTM) in cancer reconstruction, the largest cohort of this type in the Australian literature. BTM represents an exciting reconstructive tool for the cancer reconstructive surgeon, with a high rate of success and low morbidity.

Application of Novosorb biodegradable temporising matrix in wounds of different aetiologies: a case series

DECLARATION OF INTEREST

The authors have no conflicts of interest to declare.

Dermal Regeneration Template in the Management and Reconstruction of Burn Injuries and Complex Wounds: A Review

Background

Dermal scaffolds have created a paradigm shift for burn and wound management by providing improved healing and less scarring, while improving cosmesis and functionality. Dermal regeneration template (DRT) is a bilayer membrane for dermal regeneration developed by Yannas and Burke in the 1980s. The aim of this review is to summarize clinical evidence for dermal scaffolds focusing on DRT for the management and reconstruction of burn injuries and complex wounds.

Methods

A comprehensive search of PubMed was performed from the start of indexing through November 2022. Articles reporting on DRT use in patients with burns, limb salvage, and wound reconstruction were included with focus on high-level clinical evidence.

Results

DRT has become an established alternative option for the treatment of full-thickness and deep partial-thickness burns, with improved outcomes in areas where cosmesis and functionality are important. In the management of diabetic foot ulcers, use of DRT is associated with high rates of complete wound healing with a low risk of adverse outcomes. DRT has been successfully used in traumatic and surgical wounds, showing particular benefit in deep wounds and in the reconstruction of numerous anatomical sites.

Conclusions

Considerable clinical experience has accrued with the use of DRT beyond its original application for thermal injury. A growing body of evidence from clinical studies reports the successful use of DRT to improve clinical outcomes and quality of life across clinical indications at a number of anatomical sites.

Enabling Proregenerative Medical Devices via Citrate-Based Biomaterials: Transitioning from Inert to Regenerative Biomaterials

Regenerative medicine aims to restore tissue and organ function without the use of prosthetics and permanent implants. However, achieving this goal has been elusive, and the field remains mostly an academic discipline with few products widely used in clinical practice. From a materials science perspective, barriers include the lack of proregenerative biomaterials, a complex regulatory process to demonstrate safety and efficacy, and user adoption challenges. Although biomaterials, particularly biodegradable polymers, can play a major role in regenerative medicine, their suboptimal mechanical and degradation properties often limit their use, and they do not support inherent biological processes that facilitate tissue regeneration. As of 2020, nine synthetic biodegradable polymers used in medical devices are cleared or approved for use in the United States of America. Despite the limitations in the design, production, and marketing of these devices, this small number of biodegradable polymers has dominated the resorbable medical device market for the past 50 years. This perspective will review the history and applications of biodegradable polymers used in medical devices, highlight the need and requirements for regenerative biomaterials, and discuss the path behind the recent successful introduction of citrate-based biomaterials for manufacturing innovative medical products aimed at improving the outcome of musculoskeletal surgeries.

Using BTM to reconstruct a complex dorsal hand wound with segmental loss of EDC tendon: Case report and review of the literature

We present the case of a 65 year old man who sustained a complex dorsal hand degloving injury with segmental loss of EDC tendon to middle finger, which was reconstructed using BTM. He returned to near full function despite not having a tendon reconstruction, and the uninjured tendons were able to glide without restriction beneath the BTM. We review the case and the literature surrounding the use of BTM in this clinical scenario.

Clinical outcomes and resource utilisation in patients with major burns treated with NovoSorb® BTM

INTRODUCTION

Patients with major burns can undergo temporary coverage while skin graft donor sites heal, where dermal templates have an emerging role. The aim of this study was to evaluate the clinical outcomes and resource utilisation in patients with major burns treated with a bilayer biodegradable synthetic matrix (NovoSorb BTM).

METHOD

This retrospective cohort study included patients admitted to the Royal Brisbane and Women's Hospital Adult Burn Unit with burns to at least 40 % TBSA who survived their acute admission. Patients treated from July 2017 to June 2022 with BTM were compared with patients with similar injuries treated using cadaveric allograft as temporising full thickness wound coverage between January 2013 and June 2017. Outcomes measures included number of operations, total operative time, hospital and intensive care unit (ICU) length of stay (LOS), cadaveric allograft and BTM use, and blood product use. Unadjusted comparisons were made with Wilcoxon Rank-Sum tests and Fisher's exact tests. Multivariate linear regression was used to adjust for the effect of TBSA on each outcome.

RESULTS

Fifty-five patients were included (78 % male), 22 of whom were treated with BTM. We found no significant differences in age, sex, or TBSA between groups. One patient had half of the BTM removed due to infection and replaced with allograft. Patients treated with BTM had significantly less operative theatre time (median 1361.5 min [BTM] vs 1768 min [no BTM], P = 0.044). Number of operations, allograft use, hospital and ICU LOS, and blood product use were similar between groups. Adjusted models accounting for TBSA supported unadjusted models.

CONCLUSION

Resource utilisation and clinical outcomes were similar in patients with at least 40 % TBSA treated with BTM and those who were treated with allograft before the introduction of BTM. Patients treated with BTM had significantly less total operative time and no difference in number of operations, allograft use and ICU LOS.

Ovine Forestomach Matrix in the Surgical Management of Complex Volumetric Soft Tissue Defects: A Retrospective Pilot Case Series

Background

Volumetric soft tissue loss is an urgent surgical issue and can frequently lead to suboptimal outcomes for patients due to significant soft tissue loss, compromised vital structures, and contamination. Ovine forestomach matrix (OFM) has demonstrated clinical success in the surgical management of soft tissue defects, especially in contaminated fields, and provides an effective option for immediate coverage of exposed vital structures before definitive closure.

Methods

This retrospective pilot case series (n = 13 defects) evaluated the clinical effectiveness of OFM (graft and/or particulate formats) in the surgical management of contaminated volumetric soft tissue defects. Patients presented with significant soft tissue loss, often with exposed viscera, tendon, bone, or muscle, and were treated with OFM as part of their inpatient surgical management. All patients had at least 1 significant comorbidity with the potential to complicate their healing trajectory. The primary study endpoint was time to 100% granulation tissue coverage (days), and the secondary endpoint was any device-related postoperative complications.

Results

A total of 13 volumetric soft tissue defects were evaluated in 10 patients who underwent surgical reconstruction. Mean defect age was 3.5 ± 5.6 weeks, and mean area was 217.3 ± 77.9 cm2. Most defects had exposed structures (85%), and all defects were Centers for Disease Control and Prevention grade 2 or higher. Mean time to 100% granulation tissue formation was 23.4 ± 9.2 days, with a median product application of 1.0. Staged reconstruction was used in 7 of 13 defects, with the remainder (6 of 13) left to heal via secondary intention using standard wound care protocols. There were no major postoperative infections or adverse events (mean follow-up, 7.4 ± 2.4 weeks.).

Conclusions

This retrospective pilot case series builds on a growing body of evidence that OFM can be utilized to facilitate the formation of functional, well-vascularized soft tissue in large contaminated volumetric soft tissue defects.

The Use of Intact Fish Skin Grafts in the Treatment of Necrotizing Fasciitis of the Leg: Early Clinical Experience and Literature Review on Indications for Intact Fish Skin Grafts

BACKGROUND

Necrotizing fasciitis (NF) is a serious infectious disease that can initially place the patient's life in danger and, after successful surgical and antibiotic treatment, leaves extensive wounds with sometimes even exposed bones and tendons. Autologous skin grafts are not always possible or require adequate wound bed preparation. Novel intact fish skin grafts (iFSGs; Kerecis® Omega3 Wound, Kerecis hf, Isafjördur, Iceland) have already shown their potential to promote granulation in many other wound situations. Faster wound healing rates and better functional and cosmetic outcomes were observed due to their additionally postulated anti-inflammatory and analgesic properties. Therefore, iFSGs may also be essential in treating NF. We present our initial experience with iFSGs in treating leg wounds after NF and review the literature for the current spectrum of clinical use of iFSGs.

CASE PRESENTATIONS

We present two male patients (aged 60 and 69 years) with chronic or acute postsurgical extensive leg ulcers six weeks and six days after necrotizing fasciitis, respectively. Both suffered from diabetes mellitus without vascular pathologies of the lower limbs. A single application of one pre-meshed (Kerecis® Graftguide) and one self-meshed 300 cm2 iFSG (Kerecis® Surgiclose) was performed in our operation room after extensive surgical debridement and single circles of negative wound pressure therapy. Application and handling were easy. An excellent wound granulation was observed, even in uncovered tibia bone and tendons, accompanied by pain relief in both patients. Neither complications nor allergic reactions occurred. The patients received autologous skin grafting with excellent functional and cosmetic outcomes.

CONCLUSIONS

iFSGs have the potential to play a significant role in the future treatment of NF due to the fast promotion of wound granulation and pain relief. Our experience may encourage surgeons to use iFSGs in NF patients, although high-quality, large-sized studies are still required to confirm these results. The observed effects of iFSGs on wounds associated with NF may be transferred to other wound etiologies as well.

How to Select an Extracellular Matrix for Wound Repair: A Comprehensive Review

Background

An extracellular matrix (ECM) is a network of proteins and other molecules that provide support and structure to cells and tissues in the body. Since its discovery in 1930, researchers have reproduced the ECM through an array of evolving technologies, developing products that accelerate healing times, minimize scarring, and reduce pain. When selecting which ECM product to use, physicians rely on personal experience while considering wound location, type of tissue lost, exposed structures, chronicity, and even the patient's religious preferences. While comparison trials between a few different types of ECMs exist, there lacks a thorough investigation that assesses a majority of ECMs against each other.

Methods

Herein, we conducted a literature review using the PubMed database and utilized 71 articles to identify the best ECM for wound healing and positive patient outcomes. The primary search terms included extracellular matrix, xenograft, porcine, bovine, allograft, bioengineered matrix, acellularized fish skin, wounds, wound healing, and wound care. We did not exclude any specific type of research, but predominantly reviewed clinical trials, case series, and other review articles. We focused on the most popular and commonly used ECMs and constructed our results into the Table.

Results

We compared the indications, advantages, and disadvantages of each ECM and concisely illustrated these findings to provide a guide on how to select an ECM (Table). Allografts, whether they are glycerol or cryopreserved, suffice as a treatment choice and are superior to exposure healing. However, they do not produce healing at the same rate or quality as bioengineered matrices, porcine and bovine xenografts, or acellularized fish skin (AFS). Bioengineered matrices and porcine and bovine xenografts offer antimicrobial properties, low immunogenicity, cost effectiveness, and availability. The compromise with these ECMs is with healing times and cosmesis. Acellularized fish skin (AFS) provides diverse utility, antimicrobial activity, low immunogenicity, faster healing times, and cosmetic superiority. However, AFS yields a potential cost burden and is not plentiful or easily accessible in some parts of the world.

Conclusions

Our findings assist in removing the subjectivity component of selecting an ECM and suggest further comparison or head-to-head trials would yield a more algorithmic approach to wound healing. We suggest to consider implementing the Disabilities of the Arm, Shoulder, and Hand (DASH) score as an additional objective comparison method in these future trials.

The use of NovoSorb biodegradable temporising matrix in wound management: a literature review and case series

OBJECTIVE

NovoSorb (Poly-Novo Ltd, Australia) biodegradable temporising matrix (BTM) is a novel artificial dermal matrix. Previous literature is weighted towards its use in burns reconstruction; however, this paper describes its use within a range of wound aetiologies. The authors present one of the largest and most diverse case series to date, and aim to provide an independent benchmark of clinical practice.

METHOD

A retrospective observational study was performed. Patient demographics and clinical data (wound aetiology, site, total body surface area (TBSA), wound bed, number of debridements, time to BTM integration, time to skin grafting) were collected and subgroup analysis preformed.

RESULTS

The cohort consisted of 37 patients (acute trauma wounds, n=19; hard-to-heal wounds, n=9; acute infections, n=6; cancer, n=3). Successful BTM integration, allowing subsequent split-thickness skin grafting (STSG), occurred in 70% of cases, despite an overall complication rate of 51%. Mean time from BTM application to STSG was 53 days. There was no difference in STSG outcomes when grafting was performed either before or after the six-week BTM application period. There was no difference when various wound beds (fascia, tendon, periosteum) were compared. Patients >65 years of age were more likely to experience complications; however, this did not affect the speed of integration. The relation of diabetes and smoking to overall integration had no statistical significance.

CONCLUSION

In comorbid patients in particular, the time between BTM application and STSG may be longer than the manufacturer's recommendation. Furthermore, data suggest greater wound bed optimisation and closer interval monitoring in hard-to-heal/malignant wounds, and in older patients and patients with comorbidities. However, BTM appears robust (even in infection) and is showing promise as a useful reconstructive tool.

NovoSorb Biodegradable Temporizing Matrix for Reconstruction of Multiplanar Degloving Injury of the Upper Limb

Originally described as “wringer injuries” by MacCollum in 1938,¹ traumatic multiplanar degloving injuries that occur as the result of the hand, forearm or arm being drawn between the rollers of a machine are functionally devastating and present a significant reconstructive challenge. Revascularization and comprehensive excision of devitalized bone and soft tissue, followed by appropriate skeletal fixation and vascularized soft tissue cover are the mainstays of management. To date, published case series have described local flaps and free tissue transfer for coverage of wounds that involve exposed vital structures such as nerves, vessels, and tendons.² NovoSorb biodegradable temporizing matrix (BTM; PolyNovo Biomaterials Pty Ltd, Melbourne, Australia) is a bilayer bioabsorbable synthetic polymer dermal substitute, which has the ability to integrate into large wound beds and is resistant to infection.³ BTM comprises a bioabsorbable, polyurethane matrix that allows for cellular infiltration and a temporary nonbiodegradable, nonporous polyurethane layer, which limits moisture loss and provides a barrier to bacteria. Here we describe the successful use of BTM in the staged reconstruction of a high-energy industrial roller injury in an adolescent patient.

A Risk-Benefit Review of Currently Used Dermal Substitutes for Burn Wounds

While split-thickness autologous skin grafts remain the most common method of definitive burn wound closure, dermal substitutes have emerged as an attractive option. There are many advantages of utilizing a dermal substitute, notably reducing the need for donor tissue and subsequent iatrogenic creation of a secondary wound. However, there are disadvantages with each that most be weighed and factored into the decision. And most come at a high initial financial cost. There is little comparative literature of the various available and emerging products. This analysis was performed to objectively present risks and benefits of each option.

Use of Dermal Regenerative Templates for Burns

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

Engineering transplantable human lymphatic and blood capillary networks in a porous scaffold

Due to a relative paucity of studies on human lymphatic assembly in vitro and subsequent in vivo transplantation, capillary formation and survival of primary human lymphatic (hLEC) and blood endothelial cells (hBEC) ± primary human vascular smooth muscle cells (hvSMC) were evaluated and compared in vitro and in vivo. hLEC ± hvSMC or hBEC ± hvSMC were seeded in a 3D porous scaffold in vitro, and capillary percent vascular volume (PVV) and vascular density (VD)/mm² assessed. Scaffolds were also transplanted into a sub-cutaneous rat wound with morphology/morphometry assessment. Initially hBEC formed a larger vessel network in vitro than hLEC, with interconnected capillaries evident at 2 days. Interconnected lymphatic capillaries were slower (3 days) to assemble. hLEC capillaries demonstrated a significant overall increase in PVV (p = 0.0083) and VD (p = 0.0039) in vitro when co-cultured with hvSMC. A similar increase did not occur for hBEC + hvSMC in vitro, but hBEC + hvSMC in vivo significantly increased PVV (p = 0.0035) and VD (p = 0.0087). Morphology/morphometry established that hLEC vessels maintained distinct cell markers, and demonstrated significantly increased individual vessel and network size, and longer survival than hBEC capillaries in vivo, and established inosculation with rat lymphatics, with evidence of lymphatic function. The porous polyurethane scaffold provided advantages to capillary network formation due to its large (300-600 μm diameter) interconnected pores, and sufficient stability to ensure successful surgical transplantation in vivo. Given their successful survival and function in vivo within the porous scaffold, in vitro assembled hLEC networks using this method are potentially applicable to clinical scenarios requiring replacement of dysfunctional or absent lymphatic networks.

Treatment of Complex Wounds with NovoSorb® Biodegradable Temporising Matrix (BTM)-A Retrospective Analysis of Clinical Outcomes

Complex and chronic wounds represent a highly prevalent condition worldwide that requires a multimodal and interdisciplinary treatment approach to achieve good functional and aesthetic outcomes. Due to increasing costs of health care, an aging population and an increase in difficult-to-treat microbial colonization of wounds, complex wounds will become a substantial clinical, social and economic challenge in the upcoming years. In plastic reconstructive surgery, a variety of dermal skin substitutes have been established for clinical use. Since its approval as a dermal skin substitute in Germany, NovoSorb^® Biodegradable Temporising Matrix (BTM) has become a valuable therapeutic option for the treatment of full-thickness wound defects. The clinical data published to date are limited to case reports and small-scale case series with the main focus on single wounds. The aim of this single-center study was a retrospective analysis of our own patient collective that has received treatment with BTM for complex wounds. Overall, BTM showed to be a reliable and versatile reconstructive option, especially for patients with multiple co-morbidities and microbiologically colonized wounds. Although the preliminary findings have produced promising results, further investigation and research are warranted regarding long-term outcomes and additional clinical applications.

Double-layer biodegradable temporising matrix reconstruction for abdominal skin and soft-tissue reconstruction

Dermatofibrosarcoma protuberans (DFSP) is a rare, locally invasive dermal sarcoma. The management is generally surgical, with wide local excision (WLE) forming the mainstay of treatment. Large abdominal wall defects are most aesthetically reconstructed using pedicled or free flaps; however, these require tumour-free surgical margins, and are off-set by donor site morbidity. We describe an alternative, aesthetic and low-morbidity technique for reconstruction of a subfascial defect following WLE of DFSP in a young woman in her early 20s, using two layers of a novel synthetic dermal matrix (NovoSorbBTM). To our knowledge, a double-layer reconstruction using an artificial dermal matrix has never been described for trunk reconstruction. We found that double-layer biodegradable temporising matrix can restore the inherent thickness and pliability of skin in a partial-thickness abdominal wall defect and offers improved durability and cosmesis compared with skin grafting or indeed single layer skin substitutes alone.

The role of biodegradable temporizing matrix in the management of a patient with major burns and anorexia nervosa

Severe malnutrition secondary to anorexia nervosa results in deeper burns and significantly impacts wound healing, which represents a major challenge to burn management. The use of acellular dermal matrices, such as biodegradable temporizing matrix (BTM), is a valuable tool to overcome the surgical limitations. We describe a case of a 36-year-old female with a background of anorexia nervosa (body mass index of 12.3) presenting with a 30% total burns surface area (TBSA) burn. All of her burns were excised down to fascia due to the absence of subcutaneous fat. Her thin skin and depleted nutritional status significantly impacted reconstructive options. BTM was utilized to create a neodermis and provide adequate time to optimize the nutritional status before autologous skin resurfacing 3 weeks later, which yielded robust coverage with minimal donor site morbidity. Despite initial surgical and nutritional challenges, excellent outcomes were achieved in terms of wound healing, scar contractures and mobility.

A novel use for the biodegradable temporizing matrix

Biodegradable Temporising Matrix (BTM), a skin substitute, has been recently developed as a novel adjunct to the plastic surgeon’s reconstructive repertoire. Its use has been described in literature in a variety of settings and complex wounds, including those that previously would have been described as “non-graftable”, with favourable outcomes. We present the case of a patient with a wound to the right foot and ankle following extravasation injury. Following surgical debridement, this injury was managed with BTM, which allowed granulation and production of a “neo-dermis”. A split-thickness skin graft was subsequently applied. The characteristics of the BTM allowed the resulting skin graft and scar to be pliable, avoiding tendon tethering and joint contracture. To the authors’ knowledge, this skin substitute has not been reported in a wound of this aetiology before. It is our hope that this report will provide evidence to colleagues that this is a valuable adjunct that may be used in complex wounds.

Level of evidence: Level V, therapeutic study.

Microsurgical Reconstruction of Foot Defects: A Case Series with Long-Term Follow-Up

(1) Background: Microsurgical reconstruction of foot defects with free flaps is rare as it is a challenging task for a surgeon. For extensive defects, advanced surgical procedures, such as free flap transfer with microsurgical anastomosis, may be the last chance to avoid major amputation. The aim of the study was to examine the opportunities and risks posed by free flap reconstruction of foot defects and to illustrate in which situations reconstruction is useful on the basis of case characteristics. (2) Methods: In this study, we retrospectively analyzed data of cases with free flap reconstruction of the foot from 2007 to 2022. Therefore, demographic data, comorbidities, information about the defect situation, data on the operational procedure, and complications were evaluated. (3) Results: A total of 27 cases with free flap coverage of foot defects could be included. In 24 of these cases (89%), defect coverage was successful. In 18 patients, some form of complication occurred in the postoperative stage. The most frequently used flap was the latissimus dorsi flap, with 13 procedures. (4) Conclusions: Foot reconstruction using free flaps is a proven procedure for the treatment of larger foot defects and can offer a predominantly good functional outcome. The lengthy process and possible complications should be thoroughly discussed in advance so as to provide criteria, suitably adjusted to the individual prerequisites of the patients, for deciding whether limb salvage using advanced surgical procedures should be attempted.

Biodegradable polyurethane scaffolds in regenerative medicine: Clinical translation review

Early explorations of tissue engineering and regenerative medicine concepts commonly utilized simple polyesters such as polyglycolide, polylactide, and their copolymers as scaffolds. These biomaterials were deemed clinically acceptable, readily accessible, and provided processability and a generally known biological response. With experience and refinement of approaches, greater control of material properties and integrated bioactivity has received emphasis and a broadened palette of synthetic biomaterials has been employed. Biodegradable polyurethanes (PUs) have emerged as an attractive option for synthetic scaffolds in a variety of tissue applications because of their flexibility in molecular design and ability to fulfill mechanical property objectives, particularly in soft tissue applications. Biodegradable PUs are highly customizable based on their composition and processability to impart tailored mechanical and degradation behavior. Additionally, bioactive agents can be readily incorporated into these scaffolds to drive a desired biological response. Enthusiasm for biodegradable PU scaffolds has soared in recent years, leading to rapid growth in the literature documenting novel PU chemistries, scaffold designs, mechanical properties, and aspects of biocompatibility. Despite the enthusiasm in the field, there are still few examples of biodegradable PU scaffolds that have achieved regulatory approval and routine clinical use. However, there is a growing literature where biodegradable PU scaffolds are being specifically developed for a wide range of pathologies and where relevant pre-clinical models are being employed. The purpose of this review is first to highlight examples of clinically used biodegradable PU scaffolds, and then to summarize the growing body of reports on pre-clinical applications of biodegradable PU scaffolds.

[Autologous tissue reconstruction of the lower extremity-indications and technique]

Autologous tissue reconstruction for defect coverage of lower extremity wounds describes a broad interdisciplinary spectrum of conservative, surgical and interventional treatment options. The goals of reconstruction are a resilient and function-preserving but also esthetically acceptable wound closure, which should enable rehabilitation and the return to participation in social and working life for those affected. Depending on the wound conditions as well as on potentially occurring concomitant injuries and comorbidities, the timing and method of defect coverage is selected in an individualized approach for each patient. It is essential that the plastic surgeon is involved as early as possible in the preparation of a treatment plan and can then select the most appropriate and least invasive reconstructive procedure from the armamentarium, depending on the localization and etiology of the soft tissue defect. These vary from secondary wound closure to skin grafts up to local and free flaps.