Prevention Of Hypertrophic Scars Research Articles

Hydrogel-Based Dressings and Multidisciplinary Care in Severe Pediatric Burns: A Case Report of Successful Healing and Hypertrophic Scar Prevention

Hydrogel-Based Dressings and Multidisciplinary Care in Severe Pediatric Burns: A Case Report of Successful Healing and Hypertrophic Scar Prevention

Alexis® Orthopedic Protector Provides Wound Protection and Aids in Hypertrophic Scar Prevention in Total Hip Arthroplasty.

Total hip arthroplasty (THA) is one of the most widely performed orthopedic surgeries. Techniques for small skin incisions and preservation of muscles and tendons have been developed. However, avoiding skin complications and muscle damage due to forced deployment and surgical manipulation is challenging. This study aimed to investigate whether the use of Alexis® Orthopedic Protector (Applied Medical Resources Corp., Rancho Santa Margarita, CA, USA) affects postoperative outcomes. This was a retrospective cohort study including 118 patients who underwent primary THA by the same surgeon at our single institution between March 2021 and March 2023. Protectors were used alternately for each operation. Fifty-nine patients were in the protector-using group (P group), and 59 were in the nonprotector-using group (N group), with comparisons made between groups. Protectors were placed under the fascia in all patients. Preoperative blood tests showed no difference in renal and hepatic function between the two groups. No differences in postoperative C-reactive protein (CRP) and creatine kinase (CK) values or in the Japanese Orthopedic Association Hip Disease Evaluation Questionnaire (JHEQ) and Numerical Rating Scale (NRS) scores were observed. Postoperative redness was significantly higher in the N group than in the P group (49.2% vs. 7%). The percentage of hypertrophic scars at three months postoperatively was 18.6% in the N group and 7% in the P group. Furthermore, the Japan Scar Workshop Scar Scale (JSS) indicated that hypertrophic scars were significantly worse in the N group than in the P group (p = 0.0012). Alexis® Orthopedic Protectors can not only provide short-term wound protection but also reduce the rate and degree of hypertrophic scarring.

Minimally invasive surgical approach to model hypertrophic scarring in the rabbit ear.

Current strategies for hypertrophic scar prevention and treatment are limited. To facilitate these efforts, a minimally invasive hypertrophic scar model was created in a rabbit ear for the first time based on previous methods used to induce ischemia. Six New Zealand white rabbits (12 ears total) were studied. First, ischemia was achieved by ligating the cranial artery, cranial vein and central artery, while preserving the caudal artery, caudal vein and central vein, respectively. The relative level of ischemia induced at time of surgery, both baseline and maximum perfusion, was assessed with a fluorescent light-assisted angiography and demonstrated lower rates of perfusion in the ischemic ears. Following vascular injury, a 2-cm full thickness linear wound was created on the ventral ear and closed with 4 - 0 Nylon sutures under high tension. For each rabbit, one ear received a combination of ischemia and wounding with suture tension (n = 6), while the other ear was non-ischemic with wounding and suture tension alone (n = 6). Four weeks post-operatively, ischemic ears developed scar hypertrophy (histological scar thickness: 1.1 ± 0.2mm versus 0.5 ± 0.1mm, p < 0.05). Herein, we describe a novel, prototypical minimally invasive rabbit ear model of hypertrophic scar formation that can allow investigation of new drugs for scar prevention.

Efficacy and Safety of Pressure Therapy Alone and in Combination with Silicone in Prevention of Hypertrophic Scars: A Systematic Review with Meta-analysis of Randomized Controlled Trials.

At present, there are many kinds of hypertrophic scar treatment methods, among which pressure therapy and silicone therapy are very common and standard therapies, but whether they are used alone or in combination is still controversial. Therefore, the purpose of this systematic review was to compare the efficacy and safety of the combination of pressure therapy and silicone therapy (PTS) with pressure therapy alone (PT) in the treatment of hypertrophic scars to provide clinicians with information so that they can make better decisions. Relevant randomized controlled trials (RCTs) were collected by searching PubMed, Ovid MEDLINE, Embase, ScienceDirect, Web of Science, The Cochrane Library, Scopus, and Google Scholar databases to assess scar scores (The Vancouver Scar Scale, VSS; Visual Analog Scale, VAS) and adverse effects. We screened 1270 articles and included 6 RCTs including 228 patients. We found that height (MD = 0.15, 95%CI 0.10-0.21, p < 0.01) and pliability (MD = 0.35, 95%CI 0.25-0.46, p <0.01) had a significant difference, these two measures showed that the PTS group was superior to the PT group. Results in other aspects, such as VSS, vascularity, pigmentation, VAS, and adverse effects were similar between the two groups. There was no significant difference between PTS and PT in the overall treatment efficacy of hypertrophic scars with similar VSS and adverse effects, but PTS might have potential benefits for height and pliability. Additional studies with larger sample size and sound methodological quality are needed to confirm our conclusions. 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 .

The feasibility of negative pressure wound therapy versus standard dressings in paediatric hand and foot burns protocol: a pilot, single-centre, randomised control trial

IntroductionThe goal of paediatric hand and foot burn management is hypertrophic scar and/or contracture prevention. The risk of scar formation may be minimised by integrating negative pressure wound therapy (NPWT) as an acute care adjunct as it decreases the time to re-epithelialisation. NPWT has known associated therapeutic burden; however, this burden is hypothesised to be outweighed by an increased likelihood of hypertrophic scar prevention. This study will assess the feasibility, acceptability and safety of NPWT in paediatric hand and foot burns with secondary outcomes of time to re-epithelialisation, pain, itch, cost and scar formation.Methods and analysisThis is a single-site, pilot randomised control trial. Participants must be aged ≤ 16 years, otherwise well and managed within 24 h of sustaining either a hand or foot burn. Thirty participants will be randomised to either standard care (Mepitel®—a silicone wound interface contact dressing—and ACTICOAT™—a nanocrystalline silver-impregnated dressing) or standard care plus NPWT. Patients will be reviewed until 3 months post-burn wound re-epithelialisation, with measurements taken at dressing changes to assess primary and secondary outcomes. Surveys, randomisation and data storage will be done via online platforms and physical data storage collated at the Centre for Children’s Health Research, Brisbane, Australia. Analysis will be performed using the Stata statistical software.Ethics and disseminationQueensland Health and Griffith University Human Research ethics approval including a site-specific assessment was obtained. The findings of this study will be disseminated through clinical meetings, conference presentations and peer reviewed journals.Trial registrationRegistered with the Australian and New Zealand Clinical Trials Registry (ACTRN12622000044729, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=381890&isReview=true, registered 17/01/2022).

Phenotypic screening identifies hydroxypyridone anti-fungals as novel medicines for the prevention of hypertrophic scars

Although hypertrophic scarring affects ∼91% of burn patients annually, there is no drug to prevent this common complication. Hypertrophic scars are a result of dysregulated wound healing, characterised by persistent myofibroblast transformation and the excessive accumulation of extracellular matrix (ECM). Due to the multi-mechanistic nature of the scarring process, target-based approaches for identifying novel drugs have failed.Primary human dermal fibroblasts, derived from burn scar tissue, were exposed to transforming growth factor-beta 1 (TGF-β1) to induce myofibroblast transformation. A phenotypic screening assay, measuring alpha-smooth muscle actin (α-SMA) expression, was developed to screen 1,954 approved drugs. Drugs that elicited >80% inhibition of α-SMA expression, and >80% cell viability were progressed as candidate drugs. Anti-myofibroblast activity of the candidates was confirmed before investigating their effects on extracellular matrix (ECM) production and keratinocyte epithelial-mesenchymal transition (EMT).TGF-β1 induced myofibroblast transformation in primary human dermal fibroblasts (Emax = >3 ng/mL). The assay was optimised and validated (Z’ = 0.59), before screening 1,954 approved drugs. 90 drugs were identified as hits and hydroxypyridone anti-fungals selected for further testing. Concentration-response curves for these drugs confirmed their concentration-dependent anti-myofibroblast activity (IC50 = 1.4 – 16.7 μM). Hydroxypyridone anti-fungals were also found to successfully reduce ECM production and keratinocyte EMT.This is the first study to screen approved drugs in primary human dermal fibroblasts. Hydroxypyridone anti-fungals were found to prevent myofibroblast transformation, ECM production and keratinocyte EMT suggesting they could be repurposed to prevent hypertrophic scarring.

The Effectiveness of Intradermal Suture Technique on Hypertrophic Scar Prevention in Rats

Introduction : Hypertrophic scarring is a complication that occurs in post-surgical wounds. There are many ways to prevent scarring, but there have been no satisfactory methods yet. Moreover, no studies investigated the effectiveness of intradermal sutures. Polypropylene thread can be used to repair a scar after surgery. This study aimed to prove the effectiveness of intradermal sutures using polypropylene thread on surgical scar quality.Method : The study was conducted using a randomized, controlled trial, and post-test only with 20 rats (Rattus norvegicus) as animal subjects. The wounds were made on the back, approximately 6 mm x 2 cm. Then, the rats were divided into two groups: a control group without intradermal sutures (K) and treatment group with intradermal sutures (I). Histopathological examination using Hematoxylin and Eosin (H&amp;E) staining was used to identify the fibroblast number on the 21st day. The fibrocytes number were also observed on the 12th week and the Vancouver Scar Scale (VSS) was used to assess the scar quality.Result : The number of fibroblasts and fibrocytes in the control group (K) was significantly smaller (53.60 ± 14.571; 3.20 ± 0.447) than the treatment (I) (243.20 ± 75.334; 171.40 ± 13.221). The VSS value was significantly greater in the control than the treatment.Conclusion: The intradermal sutures using polypropylene thread produced a better-quality scar after surgery compared to wounds without intradermal sutures.

Evaporation-based, co-axial lock-and-key fibrous reservoir for long-term prevention of hypertrophic scars

Many diseases and conditions such as hypertrophic scarring require long-term maintenance over the healing cycle to achieve full recovery. However, there is a lack of wound dressings that can sustain over 90 days of therapeutic release. Inspired by the enhancement of wound healing by the nanofibrous morphology and diverse structures of electrospinning, we report an evaporation-based co-axial electrospun fibrous scaffold incorporating polymer brush gatekept nanocarriers for sustained delivery of therapeutics. The release rates of the system were demonstrated to be tunable through polymer graft length, while the system experienced minimal burst release when submerged under aqueous conditions. As a proof-of-concept, we target hypertrophic scarring by loading the system with doxorubicin, which led to inhibition of fibroblast activity without interfering with cell adhesion. Application of our scaffolds on rabbit ear hypertrophic scar models displayed that our scaffolds effectively reduced collagen density and scar-related gene expression in healing tissues, with improved tissue elevation outcomes. We envision that our long-term release scaffolds will be useful in combating long unresolved clinical dilemma such as tendon adhesion and tumor regression.

Effects and Mechanisms of Medicinal Plants on Healing Scars: A Systematic Review

Background: Scars can be a cosmetic disfigurement and can tremendously impact psychological, emotional, and social well-being. Some medicinal plants exert anti-scar properties via various mechanisms of action, many of which have not been clearly defined. Objective: This study will evaluate the effects of these medicinal plants with anti-scar properties and review the known underlying mechanisms related to the treatment and prevention of hypertrophic scars. Methods: The keywords used in the literature search included (Wound healing OR Re-epithelialization OR Regeneration) AND (Medicinal plants OR Phyto* OR herb) AND (Cytokines OR Collagen OR Fibroblasts). Publications indexed in the Institute for Scientific Information (ISI) and PubMed databases were included in the review. Articles with no accessible full texts, non-English language articles, review articles, studies with non-positive effects, and studies that were not related to the study’s aim were excluded from the study. The agreement for exclusion required all authors to concur. Finally, after reviewing all available literature, 61 articles were included in this systematic review. Results: Currently available evidence shows that medicinal plants and their derivatives seem to have properties that can prevent hypertrophic scars. This is achieved by accelerating the scar healing process, reducing inflammatory cytokines, suppressing proliferation, and inducing apoptosis in scar fibroblasts by regulating several signaling pathways. Additionally, they can reduce collagen deposition and have antimicrobial effects at the wound site. Conclusion: Topical use of medicinal plants as complementary medicine with varying mechanisms of action can reduce scar formation. They exert these properties mainly due to their anti-inflammatory, antioxidant, and antimicrobial properties. Therefore, these mechanisms reduce the healing time of the wound and thus prevent the formation of hypertrophic scars. Medicinal plants can be used safely and efficiently when applied topically to improve or prevent hypertrophic scars.

The Most Current Algorithms for the Treatment and Prevention of Hypertrophic Scars and Keloids: A 2020 Update of the Algorithms Published 10 Years Ago.

Background:In 2010, this Journal published my comprehensive review of the literature on hypertrophic scars and keloids. In that article, I presented evidence-based algorithms for the prevention and treatment of these refractory pathologic scars. In the ensuing decade, substantial progress has been made in the field, including many new randomized controlled trials. To reflect this, I have updated my review.Methods:All studies were evaluated for methodologic quality. Baseline characteristics of patients were extracted along with the interventions and their outcomes. Systematic reviews, meta-analyses, and comprehensive reviews were included if available.Results:Risk factors that promote hypertrophic scar and keloid growth include local factors (tension on the wound/scar), systemic factors (e.g., hypertension), genetic factors (e.g., single-nucleotide polymorphisms), and lifestyle factors. Treatment of hypertrophic scars depends on scar contracture severity: if severe, surgery is the first choice. If not, conservative therapies are indicated. Keloid treatment depends on whether they are small and single or large and multiple. Small and single keloids can be treated radically by surgery with adjuvant therapy (e.g., radiotherapy) or multimodal conservative therapy. For large and multiple keloids, volume- and number-reducing surgery is a choice. Regardless of the treatment(s), patients should be followed up over the long term. Conservative therapies, including gel sheets, tape fixation, topical and injected external agents, oral agents, and makeup therapy, should be administered on a case-by-case basis.Conclusions:Randomized controlled trials on pathologic scar management have increased markedly over the past decade. Although these studies suffer from various limitations, they have greatly improved hypertrophic scar and keloid management. Future high-quality trials are likely to improve the current hypertrophic scar and keloid treatment algorithms further.

The Effect of Topical Corticosteroid Time of Application on Fibroblast and Type III Collagen Expression in Oryctolagus cuniculus with Deep Dermal Burn Wound (As an Indicator for the Best Time to Start Topical Corticosteroid Application in Preventing Hypertrophic Scar)

Background: Hypertrophic scar is an abnormal scar that causes physical deteriorations, psychological problems, and aesthetic issues. An excessive number of fibroblasts and collagen III expressions are histopathology indicators for the hypertrophic scar. The role of topical corticosteroids in suppressing inflammation and hypergranulation had widely demonstrated in previous studies. However, there is no study related to the application of topical corticosteroids as prevention of hypertrophic scars from burn wound found. Hence, this study aimed to examine the evidence of the effects of corticosteroid topical in decreasing the number of fibroblasts and type III collagen expression and the best time to start its application in preventing hypertrophic scars. Methods: This randomized experimental post-test only study involved 54 deep dermal burn wounds on the ventral ear of female Oryctolagus cuniculus that distributed into three groups based on the healing phases. Each group consisted of treatments and controls. Corticosteroid topical application on the first treatment group (inflammatory phase group), the second group (proliferation phase group), and the third group (remodelling phase group) was started on day 3, on day 10, and day 21, respectively. Specimens taken on day 35. Haematoxylin-Eosin and Immunohistochemically staining performed to measure the number of fibroblasts and type III collagen and to observe the epithelization and inflammation process. Results: The number of fibroblasts significantly decreased in the second treatment group (p =0.001) and followed by the first group (p = 0.016), but no significant decrease found in the third group (p = 0.430). The type III collagen decreased significantly in the second treatment group (p = 0.000) and followed by the third group (p = 0.019), but no significant decrease found in the first group. There was no statistically different number of fibroblast and type III collagen discovered between the controls. Complete epithelization found in all groups. Also, no ongoing inflammation found in all groups. Conclusion : Topical corticosteroids on deep dermal burn wound revealed to be effective in reducing the number of fibroblasts and type III collagen with no healing disruption. The proliferation phase found to be the best time to start the application of topical corticosteroids.

Tacrolimus action pathways in an ointment base for hypertrophic scar prevention in a rabbit ear model

BackgroundTacrolimus is used to prevent unaesthetic scars due to its action on fibroblast activity and collagen production modulation. ObjectivesTo evaluate the action pathways, from the histopathological point of view and in cytokine control, of tacrolimus ointment in the prevention of hypertrophic scars. MethodsTwenty-two rabbits were submitted to the excision of two 1-cm fragments in each ear, including the perichondrium. The right ear received 0.1% and 0.03% tacrolimus in ointment base twice a day in the upper wound and in the lower wound respectively. The left ear, used as the control, was treated with petrolatum. After 30 days, collagen fibers were evaluated using special staining, and immunohistochemistry analyses for smooth muscle actin, TGF-β and VEGF were performed. ResultsThe wounds treated with 0.1% tacrolimus showed weak labeling and a lower percentage of labeling for smooth muscle actin, a higher proportion of mucin absence, weak staining, fine and organized fibers for Gomori's Trichrome, strong staining and organized fibers for Verhoeff when compared to controls. The wounds treated with 0.03% tacrolimus showed weak labeling for smooth muscle actin, a higher proportion of mucin absence, strong staining for Verhoeff when compared to the controls. There was absence of TGF-β and low VEGF expression. Study limitationsThe analysis was performed by a single pathologist. Second-harmonic imaging microscopy was performed in 2 sample areas of the scar. ConclusionsBoth drug concentrations were effective in suppressing TGF-β and smooth muscle actin, reducing mucin, improving the quality of collagen fibers, and the density of elastic fibers, but only the higher concentration influenced elastic fiber organization.

Safety assessment of the prophylactic use of silicone gel sheets (Lady Care®) for the prevention of hypertrophic scars following caesarean section

This study aimed to investigate the side effects of silicone gel sheet (Lady Care®) and evaluate its prophylactic efficacy in preventing abnormal scarring. Sixty women who underwent caesarean section were recruited from September 2016 to September 2017 in this prospective study. Lady Care® was applied from the 2nd to the 6th postoperative months. Side effects of Lady Care® were evaluated through medical examinations and questionnaires. A plastic surgeon diagnosed abnormal scarring. Pruritus was diagnosed in 25 (47.2%) patients; folliculitis, four (7.5%); dry skin, four (7.5%); contact dermatitis, three (5.7%); wound infection, two (3.8%); and epidermolysis, one (1.9%), albeit with mild severity. Following Lady Care® application, no abnormal scarring and mild hypertrophic scarring was observed in 32 (64.0%) and 18 (36.0%) patients respectively. Of seven patients with pre-existing hypertrophic scars, only two showed hypertrophic scarring after Lady Care® application. Our findings support the safety and prophylactic efficacy of Lady Care®. Impact Statement What is already known on this subject? The incidence of abnormal scarring, i.e. keloid or hypertrophic scar formation after caesarean section (CS) is reported to be ∼41%. Abnormal or excessive scar formation can lead to functional limitations, pruritus, pain and cosmetic issues. Studies have also shown a prophylactic effect of the application of silicone materials against the development of hypertrophic and keloid scars, though prohibitive cost and lack of adhesiveness of such gel sheets are known factors limiting their usage. What the results of this study add? The new silicone gel sheet ‘Lady Care®’ has strong adhesive properties and is consequently not easily peeled off. Furthermore, it is easy to use and economically efficient. What the implications are of these findings for clinical practice and/or further research? This is the first clinical trial on the application of Lady Care® silicone gel sheet for the prevention of CS scarring. Our findings support the safety and prophylactic efficacy of Lady Care®.

Effect of THBS1 on the Biological Function of Hypertrophic Scar Fibroblasts.

Hypertrophic scarring is a skin collagen disease that can occur following skin damage and is unlikely to heal or subside naturally. Since surgical treatment often worsens scarring, it is important to investigate the pathogenesis and prevention of hypertrophic scarring. Thrombospondin-1 (THBS1) is a matrix glycoprotein that can affect fibrosis by activating TGF-β1, which plays a key role in wound repair and tissue regeneration; therefore, we investigated the effects of THBS1 on the biological function of hypertrophic scar fibroblasts. THBS1 expression was measured in hypertrophic scars and adjacent tissues as well as normal fibroblasts, normal scar fibroblasts, and hypertrophic scar fibroblasts. In addition, THBS1 was overexpressed or silenced in hypertrophic scar fibroblasts to determine the effects of THBS1 on cell proliferation, apoptosis, and migration, as well as TGF-β1 expression. Finally, the role of THBS1 in hypertrophic scarring was confirmed in vivo using a mouse model. We found that THBS1 expression was increased in hypertrophic scar tissues and fibroblasts and promoted the growth and migration of hypertrophic scar fibroblasts as well as TGF-β1 expression. Interestingly, we found that si-THBS1 inhibited the occurrence and development of bleomycin-induced hypertrophic scars in vivo and downregulated TGF-β1 expression. Together, our findings suggest that THBS1 is abnormally expressed in hypertrophic scars and can induce the growth of hypertrophic scar fibroblasts by regulating TGF-β1. Consequently, THBS1 could be an ideal target for treating hypertrophic scarring.

Efficacy of Silicone Gel versus Silicone Gel Sheet in Hypertrophic Scar Prevention of Deep Hand Burn Patients with Skin Graft: A Prospective Randomized Controlled Trial and Systematic Review.

Background:Burn injuries are burdensome to the public health system. Hypertrophic scars are the most common undesirable sequelae associated with burn scar contracture, resulting in reduced hand function. This study compared 2 different forms of silicone combined with pressure garment (PG) to determine the efficacy in hypertrophic scar prevention in hand burns.Methods:A systematic review was also performed, including only randomized control trials with silicone materials in burned patients. A prospective intraindividual randomized controlled trial was conducted to compare the efficacy of 3 treatment groups: silicone gel and silicone gel sheet combined with PG versus PG alone.Results:There were no significant differences in all Vancouver Scar Scale parameters. Three of 6 Patient and Observer Scar Assessment Score parameters showed significant differences among the 3 groups (P < 0.05). Scar stiffness improved at 8- and 12-weeks follow-up in both silicone gel and silicone gel sheet combined with PG; however, there was no significant difference between silicone groups. Scar thickness significantly improved at 2, 4, and 8 weeks in the silicone gel group compared with PG. Scar irregularity significantly improved at 2, 4, 8, 16, and 20 weeks in both silicone combined PG groups compared with PG alone.Conclusions:Silicone gel and silicone gel sheet combined with PG were more effective than PG alone in some aspects of the Patient and Observer Scar Assessment Score. However, there was no significant difference between the silicone gel and silicone gel sheet on the Vancouver Scar Scale.

Botulinum Toxin Type A Injection for Mammoplasty and Abdominoplasty Scar Management: A Split-Scar Double-Blinded Randomized Controlled Study.

Scars are inevitable results of surgical procedures, and prevention of them is still a major problem in the field of cosmetic surgery. Although various studies have been performed on botulinum toxin-A (BoNT-A) injection for the prevention of hypertrophic scars, the exact mechanism remains unclear. This prospective, double-blinded, randomized study was performed on 19 patients who underwent mammoplasty and abdominoplasty surgery in Razi Hospital from October 2018 to December 2019. Single session of treatment was performed, where XEOMIN was allocated to one half of the scar and 0.9% saline to the control half. 3 and 6months later, scars were assessed using the modified Stony Brook Scar Evaluation Scale (SBSES). In total, 19 patients who completed the study were analyzed. mSBSES at the third month (Pvalue < 0.001; 3.34 ± 1.59 vs 1.5 ± 1.36) and the sixth month (Pvalue < 0.001; 4.89 ± 1.83 vs 2.39 ± 1.82) showed a significant difference between the treatment and control groups. In the subset analysis, there was significant difference between BoNT-A and control in all four items including width, height, color, and scar visibility at months 3 and 6, and the BoNT-A-treated sides had higher scores in all items. BoNT-A has a significant effect on scar prevention due to mammoplasty and abdominoplasty compared to placebo and results in decreased erythema, height, width and reduces incision line visibility. Moreover, its effect increases significantly over time from months 3 to 6. 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 .

The renin-angiotensin system in cutaneous hypertrophic scar and keloid formation.

Hypertrophic scar and keloid are two types of fibroproliferative conditions that result from excessive extracellular matrix production. The underlying pathological mechanism is not entirely clear. Activation of the renin-angiotensin system (RAS) is associated with fibrosis in various organs. RAS components including angiotensin II (Ang II), angiotensin AT1 and AT2 receptors, and angiotensin-converting enzyme (ACE) are expressed in the skin and act independently from the plasma RAS. AT1 receptors, which are usually the dominating receptor subtype, promote fibrosis and scar formation, while AT2 receptors inhibit the aforementioned AT1 receptor-coupled effects. Elevated angiotensin II (Ang II) levels acting on the AT1 receptor contribute to skin scar formation through increased expression of inflammatory factors such as interleukin-6 (IL-6), angiogenic factors such as vascular endothelial growth factor (VEGF) and fibrinogenic factors such as transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF), while at the same time suppressing the anti-fibrotic tissue inhibitors of matrix metalloproteinase (TIMPs). First, small clinical trials have provided evidence that inhibition of the ACE/Ang II/ AT1 receptor axis may be effective in the treatment of hypertrophic scars/keloids. This review provides a detailed overview of the current literature on the RAS in skin, wound healing and scar formation and discusses the translational potential of targeting this hormonal system for treatment and prevention of hypertrophic scars and keloids.

The Latest Strategy for Keloid and Hypertrophic Scar Prevention and Treatment: The Nippon Medical School (NMS) Protocol.

In 2006, we established a scar/keloid-specialized unit in the Department of Plastic, Reconstructive, and Aesthetic Surgery at Nippon Medical School (NMS) in Tokyo, Japan. In the ensuing 15 years, we treated approximately 2,000 new scar/keloid patients annually. This extensive experience has greatly improved the efficacy of the treatments we offer. Therefore, we discuss here the latest NMS protocol for preventing and treating keloids and hypertrophic scars. While this protocol was optimized for Japanese patients, our experience with a growing body of non-Japanese patients suggests that it is also effective in other ethnicities. The extensive evidence-based experience underlying the NMS protocol suggests that it may be suitable as the foundation of a standard international prevention/treatment algorithm for pathological scars.

A Prospective Randomized Double-blind study of silicone gel plus Herbal Extracts Versus Placebo in Pre-sternal hypertrophic scar prevention and amelioration

ObjectivePost-surgical hypertrophic scar is more frequently reported in Asians. Many modalities can treat scars but there have not been any publications to define the efficacy of silicone gel plus herbal extracts for scar prevention or amelioration. Design48 patients, who underwent median sternotomy were randomized and double-blinded to 2 groups to use topical silicone gel plus herbal extract gel or placebo for 6 months. Patients were treated either with topical silicone gel plus herbal extract gel or control using only placebo for 6 months. The scars were observed by experienced plastic surgeons using the Vancouver scar scale. SettingA single tertiary care center at Khon Kaen University. Paticipants48 patients who underwent median sternotomy were enrolled in this study. All patients were aged over 18 years. All the wounds were sutured with polyglycolic 4/0 subcuticular suture material and did not receive other scar management before participating in this study. InterventionThe silicone gel plus herbal extract gel (Bangkok Botanica, Bangkok, Thailand) in semi-liquid form was formulated from 15% Herbal extract (Allium Cepa extract, Centella Asiatica extract, Aloe Vera extract and Paper Mulberry extract), 50% polydemethysiloxane, 30% cyclopentasiloxane and 5% silica. The placebo gel was a composite of water, acrylate, C10-30 alkyl acrylate cross-polymer, polysorbate 20 and fragrance that was similar in color and consistency as that of the active gel and packed in the similar sealed packages. Main outcome measuresThe scar was assessed using the Vancouver scar scale to determine pigmentation, vascularity, pliability and height. Resultsthe study showed the silicone gel plus herbal extract gel could improve scar amelioration in height (p = 0.005) and pliability (p < 0.001) when compared to the placebo. The vascularity and pigmentation showed improvement using silicone gel plus herbal extracts but the improvement was not statistically significant. ConclusionThe silicone gel plus herbal extracts gel was effective for scar improvement in median sternotomy wounds.

Free tissue transfer for burns reconstruction: A single-site experience

This study reviews free tissue transfer (FTT) surgery for both acute wound and reconstructive scar management of burn injuries at a UK burns unit over a 10-year period. Thirty eight patients underwent 46 FTTs, or free flaps, as part of their burn injury pathway. For the cohort of patients, there was one flap failure, which occurred for a secondary scar reconstruction. It is noted that FTT was successful for all seven acute or primary interventions. Anterolateral thigh flap was the most frequently performed (57%); followed by parascapular flaps (22%) of which 43% were pre-expanded. A method of pre-expansion for neck contractures and a novel technique of anchoring this flap to the pre-tracheal fascia are described here. This can provide the patient with good neck contouring by using the capsule to hitch the flap into a good position. It is clear that further work is required to study the prevention of hypertrophic scarring that can occur at the interface between flap and adjacent skin, where occurrence rate in this cohort was 17%. It is proposed that FTT now provides a viable solution both to the coverage of complex burn wounds and to the revision of scar contractures. Consensus over an FTT protocol for the primary management of open burn wounds is seen as the logical next step for this surgical intervention.