The use of dermal regeneration template (Pelnac®) in acute full-thickness wound closure: A case series

Usage of Dermal Regeneration Templates (Pelnac) for Coverage of Exposed Hand Tendons in Acute Setting

Background

The loss of soft tissue coverage of tendons is a challenging reconstructive problem after acute hand trauma. Subsequent tendon adhesions and the loss of range of movement in addition to the poor aesthetic outcome and donor site scarring should be avoided when deciding the plan of management. Pelnac is one of the commonly used skin substitutes in reconstructive surgery that can be used for coverage of exposed tendons, but the postoperative functional outcome needs to be addressed in detail.

Methods

Twenty-six patients with acute isolated tendon injuries distal to the wrist joint were included. Two-stage reconstructive procedures were performed; the first one was the application of Pelnac. The second stage was carried out after the complete integration of Pelnac via the application of a split-thickness graft. The function outcome assesses the return of the normal range of motion to the affected hand and the QuickDASH score questionnaire. The aesthetic outcome was assessed using the Vancouver scar scale.

Results

The Pelnac was integrated in 100% of cases, with complete grafts taken in 22 of 26 patients. The mean QuickDASH score was 20.5 ± 15.7, and mean Vancouver scar scale was 3.53 ± 3.2. The full range of motion returned in 22 of 26 patients.

Conclusions

Using Pelnac to cover the exposed hand tendons in an acute setting is a convenient and efficient procedure with minimal morbidity. It can offer a good option for their coverage with preservation of hand function and acceptable aesthetic outcome.

The Benefits of Using Platelet-rich Plasma with Dermal Substitutes for Extremity Posttraumatic Skin Defects: A Short-term Outcome

Background

Skin injuries are very common. Skin grafting is an ongoing wound management procedure. The artificial dermis, PELNAC, has been considered in the treatment of several acute and chronic skin injuries. Platelet-rich plasma (PRP) is blood plasma with a platelet count higher than the baseline. It is presumed to act in a synergetic pattern to promote the healing of wounds. This study was conducted to assess the potential benefit of adding PRP to PELNAC as adjuvant therapy in treating posttraumatic skin.

Methods

In this study, adult patients who were admitted to the hospital with extremity traumatic skin and soft tissue defects with exposed bare bone, exposed tendons, or exposed cartilage in the period between October 2019 and March 2021 were allocated to either being managed with dermal substitute (PELNAC) together with PRP (group I) or PELNAC alone (group II).

Results

Patients in group I showed a higher mean graft take rate and a lower mean time for neovascularization of the acellular dermal matrix, with a statistically highly significant difference. The Vancouver Scar Scale values showed no significant difference in either group. The PRP-treated group showed statistically significant shorter hospital stays.

Conclusions

The addition of PRP to the treatment protocol showed better outcomes in terms of graft take rate, time for neovascularization of acellular dermal matrix, and length of hospital stay, with no side effects. The present study findings emphasize the promising outcome of PRP in addition to the standard treatment of complex wounds to achieve rapid and safe healing.

The Expanded Application of the Acellular Dermal Matrix: Traumatic Nail Bed Defect of the Digits

Reconstruction of traumatic nail bed defects in the digits is a frequently encountered procedure, yet often presents many challenges. In such scenarios, staged procedures may be required with significant limitations in shape and increased donor site morbidity, particularly when multiple defects are present. In this study, we introduce a simple method for the reconstruction of nail bed defects using an acellular dermal matrix (ADM). The study involved 19 digits with nail defects, which underwent reconstruction using an ADM graft. The surgical procedure was performed on all patients on the day of injury, after which they were promptly discharged. The dimensions of the defect ranged from 0.5 × 0.5 cm to a maximum of 2 × 3 cm (average, 0.9 × 1.4 cm). Final examinations were performed at postoperative 5-11 months (average, 6.6 months). All ADM grafts were successfully taken. Nail growth was observed at an average of 4 months after surgery in the treated finger. The surgical results were retrospectively evaluated using the Zook criteria. Outcomes were "excellent" in 11 patients (57.9%), "very good" in five patients (26.3%), "good" in two patients (10.5%), and "fair" in one patient (5.2%). The expanded application of ADM explored in this study illustrates a straightforward method for the reconstruction of traumatic nail bed defects, providing effective results in a single stage without incurring donor site morbidity.

Oxygen transmission rates of skin substitutes and graft survival

AIM

Oxygen is required for cell migration into the scaffold and for the survival of the overlying graft in the use of a single-layer scaffold. In the absence of diffusion from the avascular wound base, such as in areas above the bone/tendon, oxygen delivery from the lateral edges of the scaffold is important. This study compared the oxygen permeability of skin scaffolds, currently commercially available in Turkey (Nevelia®, MatriDerm®, and Pelnac®), in the lateral plane.

MATERIALS AND METHODS

To measure oxygen permeability, an interconnected closed system was created. Oxygen permeability was evaluated based on the color change that occurred as a result of the reaction of iron with oxygen. After the dermal matrices placed in the closed system were exposed to oxygen, the color change on the surface of the dermal matrices was measured, and electron microscopic images were recorded to compare deformation before and after the procedure.

RESULTS

Two scaffolds did not show deformation after the procedure while Pelnac® had minimal deformation. The oxygen rates on the nitrogen side of the test apparatus were found to be 29%, 34%, and 27% for Nevelia®, MatriDerm®, and Pelnac®, respectively; and the oxygen transmission lengths (length of color change) of these scaffolds in the lateral plane were 1, 2, and 0.5 cm, respectively.

CONCLUSION

Although none of the scaffolds showed significant deformation, and all continued to exhibit their scaffold properties after the procedure, MatriDerm® was determined to be the most suitable scaffold for use in avascular areas, with a 2-cm oxygen transmission length in terms of lateral oxygenation.

Safety and Efficacy of Kartigen® in Treating Cartilage Defects: A Randomized, Controlled, Phase I Trial

Here, we aimed to investigate the safety and preliminary efficacy of Kartigen^®, a matrix with autologous bone marrow mesenchymal stem cell-derived chondrocyte precursors embedded in atelocollagen. As a surgical graft, Kartigen^® was implanted onto the cartilage defects at the weight-bearing site of the medial femoral condyle of the knee. Fifteen patients were enrolled and stratified into two groups, undergoing either Kartigen^® implantation (n = 10) or microfracture (control group, n = 5). The primary endpoint was to evaluate the safety of Kartigen^® by monitoring the occurrence of adverse events through physician queries, physical examinations, laboratory tests, and radiological analyses for 2 years. There were no infections, inflammations, adhesions, loose body, or tumor formations in the Kartigen^®-implanted knees. The preliminary efficacy was assessed using the International Knee Documentation Committee (IKDC) score, visual analog scale, and second-look arthroscopy. The postoperative IKDC scores of the Kartigen^® group significantly improved in the 16th week (IKDC = 62.1 ± 12.8, p = 0.025), kept increasing in the first year (IKDC = 78.2 ± 15.4, p < 0.005), and remained satisfactory in the second year (IKDC = 73.6 ± 13.8, p < 0.005), compared to the preoperative condition (IKDC = 47.1 ± 17.0), while the postoperative IKDC scores of the control group also achieved significant improvement in the 28th week (IKDC = 68.5 ± 6.1, p = 0.032) versus preoperative state (IKDC = 54.0 ± 9.1). However, the IKDC scores decreased in the first year (IKDC = 63.5 ± 11.6) as well as in the second year (IKDC = 52.6 ± 16.4). Thirteen patients underwent second-look arthroscopy and biopsy one year after the operation. The Kartigen^® group exhibited integration between Kartigen^® and host tissue with a smooth appearance at the recipient site, whereas the microfracture group showed fibrillated surfaces. The histological and immunohistochemical analyses of biopsy specimens demonstrated the columnar structure of articular cartilage and existence of collagen type II and glycosaminoglycan mimic hyaline cartilage. This study indicates that Kartigen^® is safe and effective in treating cartilage defects.

Atelocollagen-Embedded Chondrocyte Precursors as a Treatment for Grade-4 Cartilage Defects of the Femoral Condyle: A Case Series with up to 9-Year Follow-Up

We demonstrated the safety and efficacy of autologous chondrocyte precursor (CP) cell therapy in repairing Grade 4 cartilage defects of medial femoral condyles. The autologous bone marrow mesenchymal stem cells of each participant were isolated, amplified, and then differentiated into CPs in atelocollagen. Neotissues made of CPs were implanted into cartilage defects with an average cell density of 4.9 ± 2.1 × 10⁶ cells/cm² through arthrotomy. The knee function was evaluated with the International Knee Documentation Committee (IKDC) subjective knee form. Patients' knee functions significantly improved by the 28th week (IKDC score = 68.3 ± 12.1), relative to the initial functionality before the CP therapy (IKDC score = 46.1 ± 16.4, p-value = 0.0014). Nine of these twelve patients maintained good knee functions for 9 years post-implantation (IKDC score = 69.8 ± 12.3) at levels higher than the pre-implantation values (p-value = 0.0018). Patients were evaluated with MRI and arthroscopy, and the defective sites exhibited a smooth surface without a gap between the implant and host tissue. This study demonstrates that autologous CPs successfully engraft into the host tissue and result in the re-formation of hyaline-like cartilage, thereby improving the impaired knee functions. Most importantly, no adverse event was reported during this long-term follow-up period.

Efficacy and safety of skin grafting in treatment of vasculitic ulcer and pyoderma gangrenosum-A systematic review

Chronic painful ulcers caused by pyoderma gangrenosum (PG) and cutaneous vasculitis remain to be a therapeutic challenge. Skin grafts have been used with success in selected cases but are generally avoided due to the fear of pathergy. The aim of this study was to investigate the safety and efficacy of skin grafting in the treatment of primary vasculitic ulcer (PVU) and PG. MEDLINE, Embase, the Cochrane Library, Clinicaltrial.gov, and WHO International Clinical Trials Registry Platform (ICTRP) were searched from inception to March 2020. A search for grey literature was conducted in May 2020. We included studies assessing the efficacy and safety of skin grafting in the treatment of PG and PVU. Studies were only included if skin grafting was performed after establishment of PG or PVU diagnosis. A total of 721 articles was identified through the database search of which 92 were included in this study. Ten articles were identified by handsearching the reference list of included studies. Finally, 102 articles describing 212 wounds in 153 patients were included. Complete healing was found in 75.5% of the wounds. The average time to complete was 10.8 weeks (95% CI 6.1-15.6). The mean donor site healing time was 1.9 weeks (95% CI 0.52-3.20). Pathergy was reported in 8 (5.2%) patients. One patient had severe infection related to skin grafting. A statistically significant difference in the number of patients receiving preoperative (P = .0079) and postoperative (P = .002) immunosuppressive therapy was found between the groups with complete healing/reduction and no improvement/aggravation. This systematic review finds the current evidence on efficacy and safety of skin grafting in treatment of PG and PVU to be promising but limited to the size and lack of studies superior to case reports and case series. Future placebo-controlled trials are required to draw a stronger conclusion.

Development of a PHMB hydrogel-modified wound scaffold dressing with antibacterial activity

Current wound scaffold dressing constructs can facilitate wound healing but do not exhibit antibacterial activity, resulting in high infection rates. We aimed to endow wound scaffold dressing with anti-infective ability by polyhexamethylenebiguanide (PHMB). We prepared PHMB hydrogel at varying concentrations (0.25%, 0.5%, 1%, 2%) and assessed release and cytotoxicity. PHMB hydrogel was added to the wound scaffold dressing to generate a PHMB hydrogel-modified wound scaffold dressing. Wound healing and infection prevention were evaluated using a full-thickness skin defect model in rats. In vitro, the hydrogel PHMB release time positively correlated with PHMB concentration, with 1% allowing sufficiently long release time to encompass the high-incidence period (3-5 days) of infection following wound scaffold dressing implantation. Implantation of 1% PHMB hydrogel into the skin did not cause adverse responses. in vitro cytotoxicity assays showed the PHMB hydrogel-modified wound scaffold dressing did not significantly affect proliferation of fibroblasts or vascular endothelial cells, 99.90% vs 99.84% for fibroblasts and 100.21% vs 99.28% for vascular endothelial cells at 21 days. Transplantation of PHMB hydrogel-modified wound scaffold dressing/unmodified wound scaffold dressing on the non-infected wounds of rats yielded no significant difference in relative vascularization rate, 47.40 vs 50.87 per view at 21 days, whereas bacterial content of the wound tissue in the PHMB hydrogel-modified wound scaffold dressing group was significantly lower than the unmodified wound scaffold dressing group, (1.80 ± 0.35) × 10³ vs (9.34 ± 0.45) × 10³ at 14 days. Prevalence of persistent wound infection in the rats receiving PHMB hydrogel-modified wound scaffold dressing transplantation onto infected wounds was significantly lower than the unmodified wound scaffold dressing group, 30% vs 100%. PHMB hydrogel-modified wound scaffold dressing exhibited suitable antibacterial ability, and its biological activity did not significantly differ from that of the unmodified wound scaffold dressing, thereby allowing it to effectively prevent infection following wound scaffold dressing implantation.

Reconstruction of massive skin avulsion of the scrota and penis by combined application of dermal regeneration template (Pelnac) and split-thickness skin graft with vacuum-assisted closure: A case report

BACKGROUND

Although skin avulsions to male external genitalia are rare, they can be both physically and psychologically traumatic. Thus, the necessity for judicious management poses significant challenges to surgeons in order to avoid potential permanent disabilities. We report a case of massive penoscrotal skin avulsion and a composite graft was creatively applied to cover the defect which achieved good results. We believe that this case is of great reference value for fellow surgeons.

CASE SUMMARY

A 52-year-old male presented with massive traumatic avulsion of the penile and scrotal skin following mishandling of an electric drill. The avulsed skin was missing. The patient was diagnosed with massive skin avulsion of external genitalia. Following initial complete debridement of devitalized or infected tissues, Pelnac dermal substitute was secured to the defect with the assistance of negative-pressure wound closure. In the final step, the silicone layer of Pelnac was removed and a split-thickness skin graft was applied. The defect had healed at the two-month follow-up. The patient now has normal erections and satisfactory sexual function.

CONCLUSION

Our experience with this wound repair demonstrated that the combination of a dermal regeneration template and a split-thickness skin graft with vacuum-assisted closure is a safe, well-tolerated and efficient solution for the reconstruction of massive penoscrotal skin defects.

Healing of Chronic Wounds: An Update of Recent Developments and Future Possibilities

Chronic wounds are the result of disruptions in the body's usual process of healing. They are not only a source of significant pain and discomfort but also, more importantly, an unguarded port of entry for pathogens into the body. While our current understanding of this phenomenon is far from complete, findings in physiological patterns and advancements in wound healing technologies have helped develop wound management and healing solutions to this long-standing medical challenge. This review presents an overview of known wound healing mechanics, abnormalities that lead to chronic wounds, and a summary of established and new wound healing technologies. Various approaches to heal wounds are discussed, from dermal replacements to advanced biomaterial-based treatments, from cell-, synthetic-, and composite-based approaches to preclinical approaches, which make developing such products possible. While tested breakthrough products are described, the authors focused more on recently developed innovations, which are at varying stages of maturity. The review concludes with a note on future perspectives and opinions on where the field and industry are headed and where they should be. Impact Statement Wound healing is an important area of research and clinical practice, and has captured the attention of tissue engineers since the nascent beginnings of the discipline. Tissue-engineered skin was the first FDA-approved product, achieved in 1996. Despite this success, and the passage of time, healing wounds, particularly chronic wounds, remains a vexing challenge. This comprehensive review article will provide readers with a synopsis of current issues, research approaches, animal models, technologies, and products that span the continuum from early development to clinical studies, in the hope of fueling new interests and ideas to overcome this long-standing medical challenge.

Skin tissue regeneration for burn injury

The skin is the largest organ of the body, which meets the environment most directly. Thus, the skin is vulnerable to various damages, particularly burn injury. Skin wound healing is a serious interaction between cell types, cytokines, mediators, the neurovascular system, and matrix remodeling. Tissue regeneration technology remarkably enhances skin repair via re-epidermalization, epidermal-stromal cell interactions, angiogenesis, and inhabitation of hypertrophic scars and keloids. The success rates of skin healing for burn injuries have significantly increased with the use of various skin substitutes. In this review, we discuss skin replacement with cells, growth factors, scaffolds, or cell-seeded scaffolds for skin tissue reconstruction and also compare the high efficacy and cost-effectiveness of each therapy. We describe the essentials, achievements, and challenges of cell-based therapy in reducing scar formation and improving burn injury treatment.

Burn injury: Challenges and advances in burn wound healing, infection, pain and scarring

Severe burn injuries are the most traumatic and physically debilitating injuries affecting nearly every organ system and leading to significant morbidity and mortality. Early burn wound excision and skin grafting are common clinical practices that have significantly improved the outcomes for severe burn injured patients by reducing mortality rate and days of hospital stay. However, slow wound healing, infection, pain, and hypertrophic scarring continue to remain a major challenge in burn research and management. In the present article, we review and discuss issues in the current treatment of burn injuries; the advances and novel strategies developed in the past decade that have improved burn management; and also, pioneer ideas and studies in burn research which aims to enhance burn wound care with a focus on burn wound infection, pain management, treatments for scarring and skin tissue engineering.