Restoring full-thickness defects with spray skin in conjunction with dermal regenerate template and split-thickness skin grafting: a pilot study

Acellular dermal matrices in reconstructive surgery; history, current implications and future perspectives for surgeons

Large-scale defects of body in the reconstructive surgical practice, and the helplessness of their repair with autologous tissues, have been an important factor in the development of artificial biological products for the temporary, definitive, or staged repair of these defects. A major advance in the field of plastic and other reconstructive surgery in this regard has been the introduction and successful use of acellular dermal matrices (ADMs). In recent years, not only the type of tissue from which ADMs are produced, product range, diversity and areas of use have increased, but their use in reconstructive fields, especially in post oncologic breast surgery, has become highly regarded and this has favored ADMs to be a potential cornerstone in specific and well-defined surgical fields in future. It is essential that reconstructive surgeons become familiar with some of the ADM's as well as the advantages and limitations to their use. This review not only provides basic science and clinical evidence of the current use of ADMs in wide range of surgical fields but also targets to keep them as an important backdrop in the armamentarium of reconstructive surgeons. Brief considerations of possible future directions for ADMs are also conducted in the end.

Autologous Skin Cell Suspension for Full-Thickness Skin Defect Reconstruction: Current Evidence and Health Economic Expectations

Despite differing etiologies, acute thermal burn injuries and full-thickness (FT) skin defects are associated with similar therapeutic challenges. When not amenable to primary or secondary closure, the conventional standard of care (SoC) treatment for these wound types is split-thickness skin grafting (STSG). This invasive procedure requires adequate availability of donor skin and is associated with donor site morbidity, high healthcare resource use (HCRU), and costs related to prolonged hospitalization. As such, treatment options that can facilitate effective healing and donor skin sparing have been highly anticipated. The RECELL® Autologous Cell Harvesting Device facilitates preparation of an autologous skin cell suspension (ASCS) for the treatment of acute thermal burns and FT skin defects. In initial clinical trials, the approach showed superior donor skin-sparing benefits and comparable wound healing to SoC STSG among patients with acute thermal burn injuries. These findings led to approval of RECELL for this indication by the US Food and Drug Administration (FDA) in 2018. Subsequent clinical evaluation in non-thermal FT skin wounds showed that RECELL, when used in combination with widely meshed STSG, provides donor skin-sparing advantages and comparable healing outcomes compared with SoC STSG. As a result, the device received FDA approval in June of 2023 for treatment of FT skin defects caused by traumatic avulsion or surgical excision or resection. Given that health economic advantages have been demonstrated for RECELL ± STSG versus STSG alone when used for burn therapy, it is prudent to examine similarities in the burn and FT skin defect treatment pathways to forecast the potential health economic advantages for RECELL when used in FT skin defects. This article discusses the parallels between the two indications, the clinical outcomes reported for RECELL, and the HCRU and cost benefits that may be anticipated with use of the device for non-thermal FT skin defects.

Maximizing wound coverage in full-thickness skin defects: A randomized-controlled trial of autologous skin cell suspension and widely meshed autograft versus standard autografting

BACKGROUND

Traumatic insults, infection, and surgical procedures can leave skin defects that are not amenable to primary closure. Split-thickness skin grafting (STSG) is frequently used to achieve closure of these wounds. Although effective, STSG can be associated with donor site morbidity, compounding the burden of illness in patients undergoing soft tissue reconstruction procedures. With an expansion ratio of 1:80, autologous skin cell suspension (ASCS) has been demonstrated to significantly decrease donor skin requirements compared with traditional STSG in burn injuries. We hypothesized that the clinical performance of ASCS would be similar for soft tissue reconstruction of nonburn wounds.

METHODS

A multicenter, within-patient, evaluator-blinded, randomized-controlled trial was conducted of 65 patients with acute, nonthermal, full-thickness skin defects requiring autografting. For each patient, two treatment areas were randomly assigned to concurrently receive a predefined standard-of-care meshed STSG (control) or ASCS + more widely meshed STSG (ASCS+STSG). Coprimary endpoints were noninferiority of ASCS+STSG for complete treatment area closure by Week 8, and superiority for relative reduction in donor skin area.

RESULTS

At 8 weeks, complete closure was observed for 58% of control areas compared with 65% of ASCS+STSG areas (p = 0.005), establishing noninferiority of ASCS+STSG. On average, 27.4% less donor skin was required with ASCS+ STSG, establishing superiority over control (p < 0.001). Clinical healing (≥95% reepithelialization) was achieved in 87% and 85% of Control and ASCS+STSG areas, respectively, at 8 weeks. The treatment approaches had similar long-term scarring outcomes and safety profiles, with no unanticipated events and no serious ASCS device-related events.

CONCLUSION

ASCS+STSG represents a clinically effective and safe solution to reduce the amount of skin required to achieve definitive closure of full-thickness defects without compromising healing, scarring, or safety outcomes. This can lead to reduced donor site morbidity and potentially decreased cost associated with patient care.Clincaltrials.gov identifier: NCT04091672.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level I.

Plastic Surgery at War: A Scoping Review of Current Conflicts

INTRODUCTION

The scope of military plastic surgery and location where care is provided has evolved with each major conflict. To help inform plastic surgeon utilization in future conflicts, we conducted a review of military plastic surgery-related studies to characterize plastic surgeon contributions during recent military operations.

MATERIALS AND METHODS

Using a scoping review design, we searched electronic databases to identify articles published since September 1, 2001 related to military plastic surgery according to a defined search criterion. Next, we screened all abstracts for appropriateness based on pre-established inclusion/exclusion criteria. Finally, we reviewed the remaining full-text articles to describe the nature of care provided and the operational level at which care was delivered.

RESULTS

The final sample included 55 studies with most originating in the United States (54.5%) between 2005 and 2019 and were either retrospective cohort studies (81.8%) or case series (10.9%). The breadth of care included management of significant upper/lower extremity injuries (40%), general reconstructive and wound care (36.4%), and craniofacial surgery (16.4%). Microsurgical reconstruction was a primary focus in 40.0% of published articles. When specified, most care was described at Role 3 (25.5%) or Roles 4/5 facilities (62.8%) with temporizing measures more common at Role 3 and definite reconstruction at Roles 4/5. Several lessons learned were identified that held commonality across plastic surgery domain.

CONCLUSIONS

Plastic surgeons continue to play a critical role in the management of wounded service members, particularly for complex extremity reconstruction, craniofacial trauma, and general expertise on wound management. Future efforts should evaluate mechanisms to maintain these skill sets among military plastic surgeons.

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

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

The Clinical Efficacy of ReCell® Autologous Cell Regeneration Techniques Combined with Dermabrasion Treatment in Acne Scars

OBJECTIVE

To evaluate the efficacy of ReCell® autologous cell regeneration techniques combined with dermabrasion treatment on the therapy of acne scars.

METHODS

We analyzed retrospectively 78 patients with acne scars who presented to the Department of Plastic Surgery at Peking Union Medical College Hospital from May 2015 to May 2017; 30 patients were treated with dermabrasion (Group 1), and the other 48 patients were treated with ReCell® autologous regeneration techniques combined with dermabrasion (Group 2). Efficacy was evaluated through self-evaluation of the patient, third-party evaluation and photographs taken before and after treatment. The wound healing time and postoperative complication rate were also recorded.

RESULTS

The study revealed a significant difference in healing time (P < 0.001) between patients treated with dermabrasion (Group 1) and patients treated with ReCell® autologous regeneration techniques combined with dermabrasion (Group 2). The average healing time of Group 1 was 12.30 ± 1.725 days, while the average healing time of Group 2 was 5.27 ± 1.086 days. In Group 2, patient self-evaluation and third-party evaluation were more satisfactory than those of Group 1 (P < 0.001). Moreover, there were no postoperative complications in Group 2 such as pigmentation and scar hyperplasia.

CONCLUSION

The ReCell® technique is simple, minimally invasive, biocompatible and effective in the treatment of acne scars. It can shorten healing time and reduce the occurrence of postoperative complications, thereby providing a safe and effective treatment approach for patients with facial acne scars.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Initial Experience With Autologous Skin Cell Suspension for Treatment of Deep Partial-Thickness Facial Burns

Facial burns present a challenge in burn care, as hypertrophic scarring and dyspigmentation can interfere with patients’ personal identities, ocular and oral functional outcomes, and have long-term deleterious effects. The purpose of this study is to evaluate our initial experience with non-cultured, autologous skin cell suspension (ASCS) for the treatment of deep partial-thickness (DPT) facial burns. Patients were enrolled at a single burn center during a multicenter, prospective, single-arm, observational study involving the compassionate use of ASCS for the treatment of large total BSA (TBSA) burns. Treatment decisions concerning facial burns were made by the senior author. Facial burns were initially excised and treated with allograft. The timing of ASCS application was influenced by an individual’s clinical status; however, all patients were treated within 30 days of injury. Outcomes included subjective cosmetic parameters and the number of reoperations within 3 months. Five patients (4 males, 1 female) were treated with ASCS for DPT facial burns. Age ranged from 2.1 to 40.7 years (mean 18.2 ± 17.3 years). Average follow-up was 231.2 ± 173.1 days (range 63–424 days). Two patients required reoperation for partial graft loss within 3 months in areas of full-thickness injury. There were no major complications and one superficial hematoma. Healing and cosmetic outcomes were equivalent to, and sometimes substantially better than, outcomes typical of split-thickness autografting. Non-cultured, ASCS was successfully used to treat DPT facial burns containing confluent dermis with remarkable cosmetic outcomes. Treatment of DPT burns with ASCS may be an alternative to current treatments, particularly in patients prone to dyspigmentation, scarring sequelae, and with limited donor sites.

Regeneration of Functional, Full-Thickness Skin With Minimal Donor Site Contribution Using Autologous Homologous Skin Construct

Autologous skin grafts (autografts) remain the gold standard in the treatment of skin loss. For extensive wounds or burns, however, identifying adequate donor sites can be the limiting factor. Additionally, donor sites are associated with pain, risk of infection, and poor cosmetic outcomes. Many skin substitutes have been engineered as alternatives to traditional autografts. These substitutes, however, all leave something to be desired either functionally or cosmetically. This report describes the use of a new technology, autologous homologous skin constructs, to regenerate full-thickness skin grafts that maintain functional polarity, allowing important components of skin such as glands and hair follicles to regenerate. These grafts only require small samples of full-thickness skin from the patient, decreasing issues of donor site availability.

Dermal regenerative matrix use in burn patients: A systematic review

BACKGROUND

Dermal regenerative matrices (DRMs) have been used for several decades in the treatment of acute and reconstructive burn injury. The objective of this study was to perform a systematic review of the literature to assess clinical outcomes and safety profile of DRMs in full-thickness burn injury.

METHODS

Comprehensive searches of MEDLINE, EMBASE, CINAHL, and Cochrane Library were performed from 1988 to 2017. Two independent reviewers completed preliminary and full-text screening of all articles. English-language articles reporting on DRM use in patients with full-thickness burn injury were included.

RESULTS

Literature search generated 914 unique articles. Following screening, 203 articles were assessed for eligibility, and 72 met inclusion criteria for analysis. DRM was applied to1084 patients (74% acute burns, 26% burn reconstruction). Of the twelve studies that described changes in ROM, significant improvement was observed in 95% of reconstructive patients. The most frequently treated reconstructive sites were the neck, hand/wrist, lower extremity, and axilla. Vancouver scar scale was used in eight studies and indicated a significant improvement in the scar quality with DRM. The overall complication rate was 13%, most commonly infection, graft loss, hematoma formation, and contracture.

CONCLUSIONS

Although variability in functional and cosmetic outcomes was observed, DRM demonstrates improvements in ROM and scar appearance without objective regression. Essential demographic data were lacking in many studies, highlighting the need for future standardization of reporting outcomes in burns following application of dermal substitutes.

Advancements in Regenerative Strategies Through the Continuum of Burn Care

Burns are caused by several mechanisms including flame, scald, chemical, electrical, and ionizing and non-ionizing radiation. Approximately half a million burn cases are registered annually, of which 40 thousand patients are hospitalized and receive definitive treatment. Burn care is very resource intensive as the treatment regimens and length of hospitalization are substantial. Burn wounds are classified based on depth as superficial (first degree), partial-thickness (second degree), or full-thickness (third degree), which determines the treatment necessary for successful healing. The goal of burn wound care is to fully restore the barrier function of the tissue as quickly as possible while minimizing infection, scarring, and contracture. The aim of this review is to highlight how tissue engineering and regenerative medicine strategies are being used to address the unique challenges of burn wound healing and define the current gaps in care for both partial- and full-thickness burn injuries. This review will present the current standard of care (SOC) and provide information on various treatment options that have been tested pre-clinically or are currently in clinical trials. Due to the complexity of burn wound healing compared to other skin injuries, burn specific treatment regimens must be developed. Recently, tissue engineering and regenerative medicine strategies have been developed to improve skin regeneration that can restore normal skin physiology and limit adverse outcomes, such as infection, delayed re-epithelialization, and scarring. Our emphasis will be centered on how current clinical and pre-clinical research of pharmacological agents, biomaterials, and cellular-based therapies can be applied throughout the continuum of burn care by targeting the stages of wound healing: hemostasis, inflammation, cell proliferation, and matrix remodeling.

Restoration of skin pigmentation after deep partial or full-thickness burn injury

Significant skin pigmentation changes occur when patients suffer deep burn injuries. These pigmentation disorders may cause not only cosmetic and psychological issues, but more importantly it increases the risk of skin cancer or photoaging. Severe burns significantly effect on the process of repigmentation as the pigmentation is tightly regulated by cell proliferation and differentiation of melanocytes and melanocyte stem cells which are housing in the epidermis and hair follicles of the skin. In the present review, we discuss the possible mechanisms to replenish the melanocytes from the healthy epidermis and hair follicles surrounding burn wounds. The molecular mechanisms of skin repigmentation following healing of burn injuries includes the differentiation of melanoblasts into melanocytes, the distribution and responses of melanocytes and melanocyte stem cells after burn injury, and the regulation of melanin production. We also reviewed advanced therapeutic strategies to treat pigmentation disorders, such as convectional surgery, laser, UV treatment and emerging concepts in skin tissue-engineering.