Clinical applications of basic research that shows reducing skin tension could prevent and treat abnormal scarring: the importance of fascial/subcutaneous tensile reduction sutures and flap surgery for keloid and hypertrophic scar reconstruction

Clinical observations on super relaxation suture in the resection of benign skin tumor in children

BACKGROUND AND OBJECTIVE

This study compares the clinical effectiveness of super relaxation suture technique using barbed polydioxanone suture (PDS) with in-situ return needle horizontal mattress suture against conventional subcutaneous heart-shaped suture technique in resecting benign skin tumors in children.

METHODS

40 children with benign skin tumors who underwent outpatient surgery and received super relaxation suture were assigned to the observation group. The control group comprised 24 children treated with conventional subcutaneous heart-shaped suture technique after the resection of benign skin tumors. The postoperative scars of the two patient groups were evaluated.

RESULTS

After a postoperative follow-up period of 3-24 months, 38 out of the 40 patients in the observation group exhibited linear wound scars, while 2 patients presented with hyperplastic scars on their chests. In the control group comprising of 24 patients, one patient had depression scar on face, two patients displayed noticeable hyperplastic scars on scalps, and one patient developed keloid on lower limb.

CONCLUSION

Super relaxation suture technique using PDS in situ backstitch horizontal mattress suture is more effective than conventional subcutaneous heart-shaped suture technique in reducing tension post-benign skin tumor resection in children, promoting wound healing, and minimizing scar formation.

Keloids revisited: Current concepts in treatment and differential diagnosis

Keloid is a special type of scar considered prototypic of skin fibrosis. Unlike hypertrophic scars, keloids exceed the margins of the original wound, and exist over time without a quiescent or regressive phase. Although keloids do not metastasize, they exhibit tumor-like characteristics, and share many similarities. Large epidemiological study demonstrates that patients with keloids have a 1.49-fold higher risk for cancers. Keloids can lead to severe functional impairments and diminish quality of life which increases hidden costs for patients and medical systems. The main goals of treatments are to improve scar appearance, symptoms and patient's quality of life (QoL). However, the microenvironment, pathogenesis, formation and development of the keloid are complex, the efficacy of multiple treatments were limited. Therefore, this up-to-date review aimed to target the current concepts in keloid treatment and differential diagnosis. The goal is to provide a reference for doctors and researchers to improve the accuracy of diagnosis and facilitate the selection of personalized treatment methods for patients with keloids.

Recurrent Keloids: Risk Factors and Treatment Efficacy

BACKGROUND

The protocols for managing recurrent keloids remain contentious. This retrospective study analyzed both recurrent and new keloids to identify risk factors for recurrence and to evaluate various treatment strategies for recurrent keloids.

METHODS

Patients were enrolled from July 2021 to January 2024 at the Plastic Surgery Department of Tianjin Hospital. Follow-ups were scheduled at 1, 3, and 6 months and 1 year posttreatment. The Patient and Observer Scar Assessment Scale, recurrence rate, and complications were used to evaluate therapeutic efficacy.

RESULTS

A total of 85 patients with 98 keloids were enrolled, with 26 patients (30.59%) experiencing recurrent keloids. Univariate analysis identified several risk factors for recurrence, yet multivariable analysis revealed that keloids located on the thorax were significantly associated with an increased risk of recurrence. Patient and Observer Scar Assessment Scale scores showed no significant differences among various treatment subgroups at 3- and 6-month follow-ups. The injection with radiotherapy subgroup had a significantly higher recurrence rate than the other subgroups.

CONCLUSION

Keloids located on the thorax should be closely monitored and actively treated. Comprehensive surgical excision combined with radiotherapy is recommended for managing recurrent keloids because it has been demonstrated to be a safe and efficacious method.

Striking a balance between aesthetics and safety: a comparative study on the maternal and neonatal outcomes of mini-incision cesarean section

OBJECTIVE AND SIGNIFICANCE: The pursuit of aesthetic outcomes is a natural tendency for individuals, particularly for women undergoing cesarean sections, who seek to minimize abdominal scarring. The aim of this study is to compare the risks and outcomes of mini-incision cesarean sections with those of conventional incision cesarean sections.

METHODS

A total of 99 pregnant women with full-term singleton pregnancies, who delivered at the Second Nanning People's Hospital from January 2024 to September 2024, were enrolled in this study. The participants were stratified into two groups: the mini-incision group (n = 33) and the conventional incision group (n = 66). The study evaluated several variables, including the time from incision to fetal delivery (I-D), surgery duration, intraoperative blood loss, duration of postoperative antibiotic administration, post-operative hospitalization duration, incidence of wound infection, neonatal adverse outcomes, and blood routine parameters.

RESULTS

The surgery duration in the mini-incision group was significantly shorter than that in the conventional group. Furthermore, the rate of forceps-assisted delivery was significantly higher in the mini-incision group (P < 0.05 for both comparisons). However, no statistically significant differences were observed between the two groups in terms of intraoperative blood loss or maternal and neonatal outcomes, including neonatal complications, incidence of wound infection, and other maternal outcomes.

CONCLUSION

Our findings indicate that when a pregnant woman requests a mini-incision cesarean section, the procedure can be safely performed by an experienced obstetrician proficient in forceps-assisted delivery techniques, provided it is not categorized as a Category I cesarean section.

Comparison the Cosmetic Outcome of the Triangular Flap Insertion Versus Direct Linear Resection in Correction of Dog Ear Deformities on the Face-A Prospective and Randomized Controlled Trial

BACKGROUND

Compared with direct linear resection, the triangular flap insertion method is a correction method that purportedly reduces the incision tension of dog ears deformity. Randomized clinical trials comparing these 2 methods seem to be limited or absent.

OBJECTIVE

A randomized study was planned to compare the cosmetic effect and scar in the defect area between the triangular flap insertion method and direct linear resection in the repair of dog ear deformities after the suture of the facial circular defect.

METHODS

The authors' study was prospective, 2-arm, randomized, evaluator-blinded clinical trial in a single-center outpatient academic plastic surgery center. Patients were eligible if they or their parents were able to provide informed consent and had dog ear deformity higher than 8 mm at both ends of the incision after suture of a circular or oval facial defect. Each dog ear deformity at the ends of the incision, half accept direct linear random resection, the other half to accept triangular flap insert. At 3-month and 6-month follow-up, each patient and 2 blinded observers evaluated the wound using the Patient Observer Scar Assessment Scale (POSAS).

RESULTS

In all, 52 subjects completed the study. At the 3-month follow-up, there was a statistically significant difference in the mean total POSAS scores for both the blinded observer and patients, indicating a preference for the side with the triangular flap insertion method. However, at the 6-month follow-up, this difference was lost.

CONCLUSION

Three months after surgery, the triangular flap insertion method resulted in a better scar outcome than direct linear resection in correction of dog ear deformities on the face. At 6 months' follow-up, this difference diminished, with scars for both sides appearing similar.

LEVEL OF EVIDENCE

Level II.

The efficacy of sequentially comprehensive treatment based on surgery in the treatment of keloids: a retrospective study

Purpose

The objective of this study is to investigate the clinical efficacy of sequentially comprehensive treatment based on surgery and to furnish clinical evidence for the management of keloids.

Patients and methods

The patients with keloids were retrospectively analyzed who underwent surgery-based sequentially comprehensive treatment at the Plastic Surgery Department of Shandong Provincial Hospital from January 2018 to August 2021. The recurrence rate and incidence of adverse reactions were explored for all the included patients. For patients who were followed up for more than 1 year, the clinical response rate was calculated, and the chi-square test was used to analyze which factors could influence clinical effectiveness. Binary logistic analysis was performed on the factors with statistical differences. For patients with a follow-up time of less than 1-year, paired t-test was used to evaluate their Vancouver Scar Scale (VSS) before and after treatment.

Results

A total of 67 patients with 80 keloids were included. The clinical response rate was 81.5% (44/54), the recurrence rate was 15.0% (12/80) and the adverse reaction rate was 4.5% (3/67). The clinical response rate of tumor-type keloids (95.8%) was higher than that of inflammatory-type (70.0%) with a significant difference (P = 0.040). After treatment, the color, blood vessel distribution, softness, thickness, and VSS score were all decreased, and the difference was statistically significant (P < 0.001).

Conclusion

The sequentially comprehensive treatment based on surgery has a significant curative effect, as well as a low recurrence rate and a low adverse effect rate. The type of keloid has a statistically significant effect on clinical efficacy, and tumor-type keloids are more suitable for sequentially comprehensive treatment based on surgery.

Finite Element Analysis of the Stress Changes Associated With the Growth of Acne Keloids

Background

Almost half of all spontaneously occurring keloids are acne keloids on the anterior chest. These keloids often grow in a crab-claw shape due to predominant tractional stresses on the scar; such stresses are risk factors for keloid growth/progression. To understand the relationship between acne keloid growth and mechanical stress, we conducted finite element analysis (FEA), measured the long/short dimensions of photographed acne keloids, and subjected acne keloids to microscopy.

Methods

FEA was conducted on 10 identically shaped ellipsoidal keloids whose long-axis length rose from 5 to 50 mm in 5-mm increments. They were embedded in the skin and subjected to traction. The stress on the keloid and its surrounding tissues was determined. Dimensions of 220 acne keloids were measured. Electron/light microscopy was conducted on the center, margins, and surrounding tissues of chest acne keloids.

Results

FEA showed that as the keloid "grew," the tractional stress centered on its core, then became evenly distributed, and then focused increasingly on the tractioned keloid margin, especially its shallow dermis. This is associated with increasing stress in the surrounding tissues at the keloid margin. Clinical dimension measurements showed that acne keloids remained round until 4-5 mm, after which they elongated rapidly. Electron microscopy showed that in the surrounding skin, fragments of keratinocyte, fibrin, and numerous cell fragments were observed just below the epidermal basement membrane.

Conclusions

Keloid-prone acne should be treated with steroid tape or other keloid therapy when it reaches 4-5 mm in diameter.

Sele-targeted siRNA liposome nanoparticles inhibit pathological scars formation via blocking the cross-talk between monocyte and endothelial cells: a preclinical study based on a novel mice scar model

BACKGROUND

Pathological scars (PS) are one of the most common complications in patients with trauma and burns, leading to functional impairments and aesthetic concerns. Mechanical tension at injury sites is a crucial factor in PS formation. However, the precise mechanisms remain unclear due to the lack of reliable animal models.

RESULTS

We developed a novel mouse model, the Retroflex Scar Model (RSM), which induces PS by applying controlled tension to wounds in vivo. RNA sequencing identified significant transcriptome changes in RSM-induced scars. Elevated expression of E-Selectin (Sele) was observed in endothelial cells from both the RSM model and human PS (Keloid) samples. In vitro studies demonstrated that cyclic mechanical stretching (CMS) increased Sele expression, promoting monocyte adhesion and the release of pro-inflammatory factors. Single-cell sequencing analysis from the GEO database, complemented by Western blotting, immunofluorescence, and co-immunoprecipitation, confirmed the role of Sele-mediated monocyte adhesion in PS formation. Additionally, we developed Sele-targeted siRNA liposome nanoparticles (LNPs) to inhibit monocyte adhesion. Intradermal administration of these LNPs effectively reduced PS formation in both in vivo and in vitro studies.

CONCLUSIONS

This study successfully established a reliable mouse model for PS, highlighting the significant roles of mechanical tension and chronic inflammation in PS formation. We identified Sele as a key therapeutic target and developed Sele-targeted siRNA LNPs, which demonstrated potential as a preventive strategy for PS. These findings provide valuable insights into PS pathogenesis and open new avenues for developing effective treatments for pathological scars.

Comparison of dual-plane micro-drop injection of botulinum toxin type A with two traditional methods for treating hypertrophic scars in the tension zone: A long-term clinical application study

BACKGROUND

Patients with hypertrophic scarring tend to experience recurrence after treatment, which often occurs in areas of the body with high skin tension.

AIMS

To evaluate better treatments aimed at reducing the risk of scar recurrence in areas of high skin tension.

METHODS

Patients were randomly divided into the following three treatment groups: botulinum toxin type A (BTA) via dual-plane micro-drop injections, triamcinolone acetonide (TAC) suspension, and CO2 via fractional CO2 laser. Interventions were implemented in all three groups once a month for three consecutive sessions. After the final treatment, scarring was evaluated at 1, 3, 6, 12, and 24 months using the Patient and Observer Scar Assessment Scale (POSAS).

RESULTS

The 3-month POSAS score for each scar indicator in the treatment groups was significantly lower than that in the preoperative groups (p < 0.001). The scar score in the TAC group decreased at 3 months and increased thereafter. For other groups, the scar score continually decreased at all time points according to the Patient Scar Assessment Scale. Based on the Observer Scar Assessment Scale, the scar score continuously decreased at all time points in the BTA group; in the TAC group, it decreased at 1 month and increased thereafter; and in the CO2 group, the scar score decreased at 3 months and subsequently stabilized.

CONCLUSIONS

All three treatment methods were effective. However, the BTA group experienced a reduced risk of scar recurrence and maintained long-term treatment effects.

Comprehensive Insights into Keloid Pathogenesis and Advanced Therapeutic Strategies

Keloid scars, characterized by abnormal fibroproliferation and excessive extracellular matrix (ECM) production that extends beyond the original wound, often cause pruritus, pain, and hyperpigmentation, significantly impacting the quality of life. Keloid pathogenesis is multifactorial, involving genetic predisposition, immune response dysregulation, and aberrant wound-healing processes. Central molecular pathways such as TGF-β/Smad and JAK/STAT are important in keloid formation by sustaining fibroblast activation and ECM deposition. Conventional treatments, including surgical excision, radiation, laser therapies, and intralesional injections, yield variable success but are limited by high recurrence rates and potential adverse effects. Emerging therapies targeting specific immune pathways, small molecule inhibitors, RNA interference, and mesenchymal stem cells show promise in disrupting the underlying mechanisms of keloid pathogenesis, potentially offering more effective and lasting treatment outcomes. Despite advancements, further research is essential to fully elucidate the precise mechanisms of keloid formation and to develop targeted therapies. Ongoing clinical trials and research efforts are vital for translating these scientific insights into practical treatments that can markedly enhance the quality of life for individuals affected by keloid scars.

Familial Spontaneous Keloids: Examining Thoracic Manifestations in Two Brothers

Keloids are complex fibroproliferative disorders with diverse clinical presentations. Spontaneous keloids (SKs) represent a rare subtype that emerges without any known preceding traumatic event. This report presents a case of familial spontaneous keloids appearing on the thoracic region in two brothers with no prior history of trauma or keloid occurrence in other family members. The lesions exhibited progressive growth over several years but responded to cycles of triamcinolone treatment. This case underscores an unusual spontaneous occurrence of keloids in the thoracic region of two siblings, highlighting the potential genetic predisposition in the aetiology of these lesions. Additionally, this instance reinforces the concept that keloids can develop spontaneously without any apparent trauma in the affected area.

Comparison of gasless transaxillary endoscopic thyroidectomy, endoscopic thyroidectomy via areola approach and conventional open thyroidectomy in patients with unilateral papillary thyroid carcinoma

BACKGROUND

Gasless transaxillary endoscopic thyroidectomy (GTET) and endoscopic thyroidectomy via the areola approach (ETA) have emerged as minimally invasive surgical techniques for managing papillary thyroid carcinoma (PTC). This study aimed to assess the surgical efficacy of endoscopic thyroidectomy (ET) as compared to conventional open thyroidectomy (COT) in PTC patients.

METHODS

Between 2020 and 2022, 571 PTC patients underwent unilateral thyroidectomy accompanied by ipsilateral central lymph node dissection. This cohort comprised 72 patients who underwent GTET, 105 ETA, and 394 COT. The analysis encompassed a comprehensive examination of patient clinicopathologic characteristics and postoperative complaints. Furthermore, the learning curve of GTET was evaluated using the cumulative summation (CUSUM) method.

RESULTS

Patients in the ET group exhibited a lower mean age and a higher proportion of female individuals. Operation time in the ET group was significantly longer. No significant differences were observed in the incidence of postoperative complications among the three groups. With regard to postoperative complaints reported three months after surgery, GTET demonstrated superior alleviation of anterior chest discomfort and swallowing difficulties. Patients who underwent ET reported significantly higher cosmetic satisfaction levels. Additionally, the learning curve of GTET was 27 cases, and the operation time during the mature phase of the learning curve exhibited a significant reduction when compared to ETA.

CONCLUSIONS

The findings of this study affirm the safety and feasibility of employing GTET and ETA for the surgical management of PTC. GTET presents an attractive surgical option, particularly for patients with unilateral PTC who place a premium on cosmetic outcomes.

Split-level folding, step-type tension-relieving suture technique, and the evaluation on scar minimization

BACKGROUND

Prevailing tension-reducing suture methods have a spectrum of issues. This study presents a straightforward yet highly efficacious suture technique known as the Split-level Folding, Step-type Tension-relieving Suture technique, which could play a pivotal role in preempting incisional scarring.

AIMS

To introduce Split-level Folding, Step-type Tension-relieving Suture technique and assess its effect on scar minimization.

METHODS

A retrospective analysis of 64 patients who underwent treatment utilizing the proposed suturing methodology. Assessment parameters included the Patient and Observer Scar Assessment Scale (POSAS), the Vancouver Scar Scale (VSS), scar width, complications, and all evaluated at 6- and 12-month postoperatively.

RESULTS

At 12-month follow-up, the POSAS and VSS scores in the normal suture group (32.58 ± 5.43, 3.58 ± 1.39) were considerably higher than the step-type suture group (29.75 ± 3.56, p = 0.0007; 2.78 ± 1.17, p = 0.0006). Moreover, the step-type suture group showcased a significantly narrower average incision scar width (1.62 ± 0.36) than the normal suture group (1.87 ± 0.42, p = 0.0004). This novel tension-relieving suture technique that effectively circumvents the occurrence of persistent localized eversion and other complications often associated with traditional tension-relieving sutures.

CONCLUSIONS

The Split-level Folding, Step-type Tension-relieving Suture technique emerges as a highly promising option for averting incisional scarring. This suture method works well for incisions on the chest, back, and extremities, resulting in significantly better long-term outcomes.

Early postoperative interventions in the prevention and management of thyroidectomy scars

Thyroidectomy scars, located on the exposed site, can cause distress in patients. Owing to the cosmetic importance of thyroidectomy scars, many studies have been conducted on its prevention and treatment. Scar formation factors mainly include inflammatory cell infiltration, angiogenesis, fibroblast proliferation, secretion of cytokines such as transforming growth factor (TGF)-β1, and mechanical tension on the wound edges. Anti-scar methods including topical anti-scar agents, skin tension-bearing devices, and local injections of botulinum toxin, as well as lasers and phototherapies, that target these scar formation factors have been developed. However, current studies remain fragmented, and there is a lack of a comprehensive evaluation of the impacts of these anti-scar methods on treating thyroidectomy scars. Early intervention is a crucial but often neglected key to control hyperplastic thyroidectomy scars. Therefore, we review the currently adopted early postoperative strategies for thyroidectomy scar reduction, aiming to illustrate the mechanism of these anti-scar methods and provide flexible and comprehensive treatment selections for clinical physicians to deal with thyroidectomy scars.

Efficacy of surgical resection and ultra-reduced tension suture combined with superficial radiation in keloid treatment

BACKGROUND

There are many available treatment options for keloid; however, single treatments are usually less effective. Therefore, more scientifically rational and effective combined treatment methods should be sought to solve the pain associated with keloids.

AIM

To explore the efficacy and safety of surgical resection and ultra-reduced tension suture combined with superficial radiation as keloid treatment.

METHODS

Fifteen keloid patients admitted to Qingdao Eighth People's Hospital from June 2020 to January 2022 were enrolled in this retrospective analysis. All patients underwent a comprehensive treatment approach comprising surgical resection, ultra-reduced tension suture incision, and superficial radiation therapy within 24 h postoperatively. The modified Vancouver Scar Scale (mVSS) and Patient and Observer Scar Assessment Scale (POSAS) were used to evaluate the treatment effect, whereas the efficacy, adverse effects, and recurrence rate were observed according to the 12-mo follow-up after treatment.

RESULTS

The mVSS and POSAS scores at 1 and 6 mo after combination treatment decreased compared to before treatment (P < 0.001), and the overall response rate was 93.3%. Only one case recurred, yielding a 6.7% recurrence rate. The incidence of local chromour sedimentation rate in 1-3 mo after radiotherapy was 33.3% (5 patients), all subsiding after 6-9 mo, without complications, such as delayed wound healing or dermatitis.

CONCLUSION

Surgical resection, super subtraction sutures, and superficial radiotherapy are treatment methods with short courses, low recurrence rates, and good safety profiles.

Scars

Wound healing occurs as a response to disruption of the epidermis and dermis. It is an intricate and well-orchestrated response with the goal to restore skin integrity and function. However, in hundreds of millions of patients, skin wound healing results in abnormal scarring, including keloid lesions or hypertrophic scarring. Although the underlying mechanisms of hypertrophic scars and keloid lesions are not well defined, evidence suggests that the changes in the extracellular matrix are perpetuated by ongoing inflammation in susceptible individuals, resulting in a fibrotic phenotype. The lesions then become established, with ongoing deposition of excess disordered collagen. Not only can abnormal scarring be debilitating and painful, it can also cause functional impairment and profound changes in appearance, thereby substantially affecting patients' lives. Despite the vast demand on patient health and the medical society, very little progress has been made in the care of patients with abnormal scarring. To improve the outcome of pathological scarring, standardized and innovative approaches are required.

Evidence-based management of keloids and hypertrophic scars in dermatology

While normal, controlled wound-healing results in scars that are nearly imperceptible, hypertrophic scars (HTS) and keloids are the result of an abnormal wound-healing process that can leave unsightly, difficult-to-treat lesions. While such scars are classically associated with surgical incisions, they may also result from burns or accidental trauma to the skin. Several different measures can be taken to prevent the formation of scars or treat those that have already formed. Prevention focuses on reducing inflammation during the wound-healing process, and minimizing tension in the lesion when appropriate. Treatments range from non-invasive modalities such as pressure therapy, topicals, and symptom management, to invasive methods such as injections, lasers, and even surgery. While some treatments, such as corticosteroid injections, have been used in the treatment of HTS and keloids for decades, other newer therapies have only been described in case reports or are still in early phases of clinical trials. Because optimal scar management will not be the same for every patient, further investigation of newer agents and methods is warranted and may benefit a great number of patients. This paper will review the evidence-based management of scars, including current widely used treatment options and promising newly emerging therapies.

Parotid Fistulas after Reconstructive Surgery for the Face and Neck Burn Contracture

A parotid fistula is a rare symptom, caused by abnormal canal between the skin and the salivary duct or gland, leading to salivary discharge from skin. A 53-year-old man suffered a severe facial, neck, and precordial flame burn, which was treated by multiple debridement and split-thickness-skin-grafts. After the release of cervical scar contracture with a distant flap, saliva discharge from small fistula became evident, following him coming to the authors' hospital for treatment of the scar contracture of the face and neck. The apertures of the fistula were located 2 cm cephalad. Computed tomography with contrast injected into the fistula revealed extension to the left parotid gland. Following from this, the site was covered with a free groin flap. Over two years after surgery, no recurrence of parotid fistula was observed.

Using Zhang's supertension-relieving suture technique with slowly-absorbable barbed sutures in the management of pathological scars: a multicenter retrospective study

Background

An ideal tension-relieving suture should be efficient for >3 months to retrieve normal tensile strength. Most preexisting suturing techniques provided tension elimination followed by relapse and scar proliferation due to absorption and cut-through of the sutures. This study introduces a simple but effective suture technique developed by a senior author (ZYX) to solve this problem.

Methods

A total of 120 patients with pathological scar (PS) had intervention treatment with the proposed suturing strategy at three centers from January 2018 to January 2021. A slowly absorbable 2-0 barbed suture was used for subcutaneous tension relieving with a set-back from the wound edge and a horizontal interval between proposed inserting points of 1 cm. The Patient and Observer Scar Assessment Scale (POSAS), scar width, perfusion and eversion of the wound edge were evaluated at 3-, 6- and 12-month follow-up. The time needed to place the tension-relieving suture was recorded and relapse was monitored for 18 months postoperatively.

Results

In total, 76 trunks, 32 extremities and 12 cervical PS were included, with an average subcutaneous tension-relieving suture time of 5 min. The Patient and Observer Scar Assessment Scale (POSAS) score decreased from 84.70 ± 7.06 preoperatively to 28.83 ± 3.09, 26.14 ± 1.92 and 24.71 ± 2.00 at 3, 6 and 12 months postoperatively, respectively (p < 0.0001). The scar widths were 0.17 ± 0.08, 0.25 ± 0.09 and 0.33 ± 0.10 cm, respectively, with perfusion significantly decreased from 213.64 ± 14.97 to 112.23 ± 8.18 at 6 months (p < 0.0001). The wound edge flattened out during the first 3 months in most cases with only two scar relapses.

Conclusions

Zhang's suture technique provides a rapid and long-lasting tension-relieving effect with ideal scar appearances and lower relapse rates in the surgical management of PS.

Close orthopedic surgery skin incision with combination of barbed sutures and running subcuticular suturing technique for less dermal tension concentration: a finite element analysis

BACKGROUND

Mechanical forces have an important role in the initiation and progression of orthopedic surgical incisions complications. To avoid incision complications with the reduction of dermal tension, surgeons may choose a buried continuous suture technique other than the traditional interrupted vertical mattress suture. Absorbable barbed sutures are widely used in orthopedics due to their convenience and reducing wound tension. The aim of this research is to compare and explain the advantages of running subcuticular suturing technique with absorbable barbed sutures for orthopedic surgical incisions closure.

METHODS

Finite element models of layered skin and two different suture techniques, running subcuticular suture and intradermal buried vertical mattress suture, ware constructed. The mechanical property difference between standard sutures and barbed sutures was modelled using different contact friction coefficient. Pulling the skin wound was simulated, and the sutures' pressure on the skin tissue was determined.

RESULTS

Compared with traditional smooth sutures, the barbed sutures effectively increased the contact force for subepidermal layers, which led the less force variation between different layers. The results also suggested that subcuticular suture caused less stress concentration compared with intradermal buried vertical mattress suture.

CONCLUSIONS

In conclusion, our study indicated that running subcuticular suturing technique with absorbable barbed sutures for orthopedic surgical incisions closure results in more uniform stress distribution in the dermis. We recommend this combination as the preferred method of skin closure in orthopedic surgery unless contraindicated.

Congress Report on the Second World Congress of Global Scar Society with Scar Academy and Japan Scar Workshop

Pathological scars (including keloids, hypertrophic scars, and scar contractures) are present with high severity among certain populations, particularly in Asians and Africans who are highly prone to develop scars. Understanding the patho-mechanism that underlies scarring, such as mechanosignaling, systemic, and genetic factors, as well as optimal surgical techniques and integrated noninvasive therapeutic methods can guide clinicians to develop treatment protocols that can overcome these issues. This report summarizes a congress at Pacifico Yokohama (Conference Center) on December 19, 2021 involving researchers and clinicians from diverse disciplines who convened to discuss current clinical, preclinical, and most recent research advances in understanding pathological scarring, keloid and hypertrophic scar management, and research progress in wound healing. Presenters described the advances in scar therapies, understanding scarring mechanisms, and scar prevention and assessments tools. Moreover, presenters addressed the challenges during the COVID-19 pandemic and using telemedicine in management of scar patients.

Affecting factors for abdominal incisional tension in surgery of dogs and cats

OBJECTIVE

Proper assessment of intraoperative abdominal incisional tension helps to select the appropriate sutures and suture method. Wound tension is usually thought to be associated with wound size, but few relevant articles have been reported. The aim of this study was to investigate the core factors influencing abdominal incisional tension and construct regression equations to judge incisional tension in clinical surgery.

METHODS

Medical records were collected from clinical surgical cases at the Teaching Animal Hospital of Nanjing Agricultural University from March 2022 to June 2022. The data collected mainly included the body weight, and the incisional length, margin, and tension. The core factors affecting abdominal wall incisional tension were screened by correlation analysis, random forest analysis, and multiple linear regression analysis.

RESULTS

Although correlation analysis showed that multiple same and deep layer abdominal incision parameters and body weight were significantly correlated with abdominal incisional tension. However, the same layer of abdominal incisional margin had the largest correlation coefficient. In random forest models, the abdominal incisional margin had the main contribution to the prediction of the same layer's abdominal incisional tension. In the multiple linear regression model, all incisional tension could be predicted by the same layer of abdominal incisional margin as the only independent variable, except for canine muscle and subcutaneous. The canine muscle and subcutaneous incisional tension were binary regressions with the same layer's abdominal incision margin and body weight.

CONCLUSION

The same layer's abdominal incisional margin is the core factor positively related to the abdominal incisional tension intraoperatively.

An Updated Review of Hypertrophic Scarring

Hypertrophic scarring (HTS) is an aberrant form of wound healing that is associated with excessive deposition of extracellular matrix and connective tissue at the site of injury. In this review article, we provide an overview of normal (acute) wound healing phases (hemostasis, inflammation, proliferation, and remodeling). We next discuss the dysregulated and/or impaired mechanisms in wound healing phases that are associated with HTS development. We next discuss the animal models of HTS and their limitations, and review the current and emerging treatments of HTS.

The effects of mechanical force on fibroblast behavior in cutaneous injury

Wound healing results in the formation of scar tissue which can be associated with functional impairment, psychological stress, and significant socioeconomic cost which exceeds 20 billion dollars annually in the United States alone. Pathologic scarring is often associated with exaggerated action of fibroblasts and subsequent excessive accumulation of extracellular matrix proteins which results in fibrotic thickening of the dermis. In skin wounds, fibroblasts transition to myofibroblasts which contract the wound and contribute to remodeling of the extracellular matrix. Mechanical stress on wounds has long been clinically observed to result in increased pathologic scar formation, and studies over the past decade have begun to uncover the cellular mechanisms that underly this phenomenon. In this article, we will review the investigations which have identified proteins involved in mechano-sensing, such as focal adhesion kinase, as well as other important pathway components that relay the transcriptional effects of mechanical forces, such as RhoA/ROCK, the hippo pathway, YAP/TAZ, and Piezo1. Additionally, we will discuss findings in animal models which show the inhibition of these pathways to promote wound healing, reduce contracture, mitigate scar formation, and restore normal extracellular matrix architecture. Recent advances in single cell RNA sequencing and spatial transcriptomics and the resulting ability to further characterize mechanoresponsive fibroblast subpopulations and the genes that define them will be summarized. Given the importance of mechanical signaling in scar formation, several clinical treatments focused on reducing tension on the wound have been developed and are described here. Finally, we will look toward future research which may reveal novel cellular pathways and deepen our understanding of the pathogenesis of pathologic scarring. The past decade of scientific inquiry has drawn many lines connecting these cellular mechanisms that may lead to a map for the development of transitional treatments for patients on the path to scarless healing.

An updated review of the immunological mechanisms of keloid scars

Keloid is a type of disfiguring pathological scarring unique to human skin. The disorder is characterized by excessive collagen deposition. Immune cell infiltration is a hallmark of both normal and pathological tissue repair. However, the immunopathological mechanisms of keloid remain unclear. Recent studies have uncovered the pivotal role of both innate and adaptive immunity in modulating the aberrant behavior of keloid fibroblasts. Several novel therapeutics attempting to restore regulation of the immune microenvironment have shown variable efficacy. We review the current understanding of keloid immunopathogenesis and highlight the potential roles of immune pathway-specific therapeutics.

Evaluating polymeric biomaterials to improve next generation wound dressing design

Wound healing is a dynamic series of interconnected events with the ultimate goal of promoting neotissue formation and restoration of anatomical function. Yet, the complexity of wound healing can often result in development of complex, chronic wounds, which currently results in a significant strain and burden to our healthcare system. The advancement of new and effective wound care therapies remains a critical issue, with the current therapeutic modalities often remaining inadequate. Notably, the field of tissue engineering has grown significantly in the last several years, in part, due to the diverse properties and applications of polymeric biomaterials. The interdisciplinary cohesion of the chemical, biological, physical, and material sciences is pertinent to advancing our current understanding of biomaterials and generating new wound care modalities. However, there is still room for closing the gap between the clinical and material science realms in order to more effectively develop novel wound care therapies that aid in the treatment of complex wounds. Thus, in this review, we discuss key material science principles in the context of polymeric biomaterials, provide a clinical breadth to discuss how these properties affect wound dressing design, and the role of polymeric biomaterials in the innovation and design of the next generation of wound dressings.

Fractional Q-Switched 1064 nm Laser for Treatment of Atrophic Scars in Asian Skin

Background and Objectives: Asian patients with Fitzpatrick skin type III-IV are a less studied subtype of patients in the medical literature. Q-Switched, 1064 nm neodymium-doped yttrium aluminum garnet (Nd: YAG) laser with a fractionated beam profile (QSF) is a new modality that was reported to be effective in the treatment of scars. This study aims to evaluate the efficacy and safety of QSF Nd: YAG laser in treating scars in Asian patients. Materials and Methods: A total of 29 Subjects were treated with 1064 nm QSF laser. Each patients had three treatments with a fractionated microlens array handpiece every 8 weeks). Efficacy of treatment was evaluated using the Goodman and Baron's quantitative grading scale before and 3 months after the last treatment. Results: All 29 patients treated had significant improvement of acne scars according to Goodman and Baron's Quantitative Global Acne Scarring Grading System. No side effect has been observed except some minor erythematous reactions in three patients. Conclusions: Our results confirm that the 1064 nm QSF Nd: YAG laser is a safe and effective technique for treating scars in Asians.

OLDER PATIENTS AND PATIENTS WITH SEVERE ARTERIOSCLEROSIS ARE LESS LIKELY TO DEVELOP KELOIDS AND HYPERTROPHIC SCARS AFTER THORACIC MIDLINE INCISION: A SURVEY-BASED ANALYSIS OF 328 CASES

BACKGROUND

Surgery is a well-known trigger of keloid and hypertrophic scarring. Sternotomy scars are subject to high skin tension, which is also known to promote pathological scarring. This suggests that sternotomies in adults associate with high pathological-scarring rates, which is also our anecdotal experience. However, this notion has never been formally examined. Therefore, we conducted a survey-based cohort study of patients who had undergone a sternotomy.

STUDY DESIGN

All consecutive Japanese adults (≥18 years) who underwent cardiovascular surgery with sternotomy in 2014-2017 were identified in 2019 by chart review and sent a questionnaire. Respondents formed the study cohort. The questionnaire presented randomly-ordered photos of representative mature, keloid, and hypertrophic scars and asked the patients to choose the image that best resembled their midline scar when it was particularly noticeable. The incidence of self-reported pathological scarring (keloids and hypertrophic scars were grouped together) and the patient demographic (age and sex) and clinical characteristics (e.g. intima media thickness of the left and right common and internal carotid arteries) that associated with pathological scarring were determined.

RESULTS

Of the 548 sternotomy patients, 328 (mean age, 67 years; 68.0% male) responded (60% response rate). Of these, 195 (59.5%) reported they had a pathological scar. Compared to mature-scar patients, pathological-scar patients had lower mean age (65 vs. 69 years, p=0.0002) and intima-media thickness (0.92 vs. 1.05 mm, p=0.028).

CONCLUSION

Sternotomy was associated with a high rate of pathological scarring. An older age and arteriosclerosis were associated with less pathological scarring.

Role of Inflammasomes in Keloids and Hypertrophic Scars-Lessons Learned from Chronic Diabetic Wounds and Skin Fibrosis

Keloids and hypertrophic scars are pathological cutaneous scars. They arise from excessive wound healing, which induces chronic dermal inflammation and results in overwhelming fibroblast production of extracellular matrix. Their etiology is unclear. Inflammasomes are multiprotein complexes that are important in proinflammatory innate-immune system responses. We asked whether inflammasomes participate in pathological scarring by examining the literature on scarring, diabetic wounds (also characterized by chronic inflammation), and systemic sclerosis (also marked by fibrosis). Pathological scars are predominantly populated by anti-inflammatory M2 macrophages and recent literature hints that this could be driven by non-canonical inflammasome signaling. Diabetic-wound healing associates with inflammasome activation in immune (macrophages) and non-immune (keratinocytes) cells. Fibrotic conditions associate with inflammasome activation and inflammasome-induced transition of epithelial cells/endothelial cells/macrophages into myofibroblasts that deposit excessive extracellular matrix. Studies suggest that mechanical stimuli activate inflammasomes via the cytoskeleton and that mechanotransduction-inflammasome crosstalk is involved in fibrosis. Further research should examine (i) the roles that various inflammasome types in macrophages, (myo)fibroblasts, and other cell types play in keloid development and (ii) how mechanical stimuli interact with inflammasomes and thereby drive scar growth. Such research is likely to significantly advance our understanding of pathological scarring and aid the development of new therapeutic strategies.

The Origin and Development of Interrupted Subcuticular Suture: An Important Technique for Achieving Optimum Wound Closure

BACKGROUND

Subcuticular suture is an important technique for achieving optimum wound closure, and there has been no comprehensive summary of subcuticular sutures to date.

OBJECTIVE

To summarize the origin and development of interrupted subcuticular suture to help clinicians improve their wound closure skills.

MATERIALS AND METHODS

A comprehensive review of subcuticular suture techniques was conducted in PubMed to summarize the advantages and disadvantages of various methods and clinical indications.

RESULTS

Buried suture is the oldest subcuticular suture technique, followed by buried vertical mattress suture, intracutaneous butterfly suture, modified/variant buried vertical mattress suture, intradermal buried vertical mattress suture, buried horizontal mattress suture, wedge-section and modified buried vertical mattress suture, set-back suture, and modified buried horizontal mattress suture, which have gradually been applied in clinical practice. Buried vertical mattress suture is currently the most widely used subcuticular suture technique.

CONCLUSION

Patients can certainly benefit from the appropriate application of subcuticular suture. There is also no single ideal method for achieving optimal results in all cases. Fully understanding the history of subcuticular suture can help doctors improve their wound closure technique.

Tissue chondrification and ossification in keloids with primary report of five cases

Keloid is commonly regarded as a benign skin tumour. Some keloids clinically exhibit hard tissue texture similar to that of cartilage or bone. We hypothesized that the keloid pathological niche environment is likely to induce keloid MSCs towards chondrogenic or osteogenic differentiation and leads to cartilage or bone‐like tissue formation. The differences in tissue ossification, histology, mechanical properties, abnormal extracellular matrices and chondrogenic/osteogenic gene expression among sclerous keloids (SKs), regular keloids (RKs) and normal skins (NKs) were carefully examined. The sporadic ossified islets existed in SK group whereas no ossified/chondrified islet was found in other groups by micro‐CT reconstruction. H&E, Masson trichrome and safranin O staining revealed lacuna‐like structures in SKs, which were featured as bone/cartilage histology. Immunohistochemical staining showed overproduction of osteoprotegerin, type I and III collagen in SK group but similar production level of aggrecan among three groups. The biomechanical analysis demonstrated the weakest compliance of SK tissues. In addition, SK fibroblasts exhibited a relatively slower proliferation rate but higher expression levels of osteogenic and chondrogenic genes among all three groups. These cell populations also showed the strongest potential for lineage transformation. In conclusion, we first reported the presence of ossified and chondrified matrices in some extremely hard keloids in the present study.

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.

Use of Closed Incision Negative Pressure Therapy (ciNPT) in Breast Reconstruction Abdominal Free Flap Donor Sites

BACKGROUND

Closed incision negative pressure therapy (ciNPT) may reduce the rate of wound complications and promote healing of the incisional site. We report our experience with this dressing in breast reconstruction patients with abdominal free flap donor sites.

METHODS

A retrospective cohort study was conducted of all patients who underwent breast reconstruction using abdominal free flaps (DIEP, MS-TRAM) at a single institution (Royal Melbourne Hospital, Victoria) between 2016 and 2021.

RESULTS

126 female patients (mean age: 50 ± 10 years) were analysed, with 41 and 85 patients in the ciNPT (Prevena) and non-ciNPT (Comfeel) groups, respectively. There were reduced wound complications in almost all outcomes measured in the ciNPT group compared with the non-ciNPT group; however, none reached statistical significance. The ciNPT group demonstrated a lower prevalence of surgical site infections (9.8% vs. 11.8%), wound dehiscence (4.9% vs. 12.9%), wound necrosis (0% vs. 2.4%), and major complication requiring readmission (2.4% vs. 7.1%).

CONCLUSION

The use of ciNPT for abdominal donor sites in breast reconstruction patients with risk factors for poor wound healing may reduce wound complications compared with standard adhesive dressings; however, large scale, randomised controlled trials are needed to confirm these observations. Investigation of the impact of ciNPT patients in comparison with conventional dressings, in cohorts with equivocal risk profiles, remains a focus for future research.

Furnishing Wound Repair by the Subcutaneous Fascia

Mammals rapidly heal wounds through fibrous connective tissue build up and tissue contraction. Recent findings from mouse attribute wound healing to physical mobilization of a fibroelastic connective tissue layer that resides beneath the skin, termed subcutaneous fascia or superficial fascia, into sites of injury. Fascial mobilization assembles diverse cell types and matrix components needed for rapid wound repair. These observations suggest that the factors directly affecting fascial mobility are responsible for chronic skin wounds and excessive skin scarring. In this review, we discuss the link between the fascia's unique tissue anatomy, composition, biomechanical, and rheologic properties to its ability to mobilize its tissue assemblage. Fascia is thus at the forefront of tissue pathology and a better understanding of how it is mobilized may crystallize our view of wound healing alterations during aging, diabetes, and fibrous disease and create novel therapeutic strategies for wound repair.

Asporin inhibits collagen matrix-mediated intercellular mechanocommunications between fibroblasts during keloid progression

Keloids are fibrotic lesions that grow unceasingly and invasively and are driven by local mechanical stimuli. Unlike other fibrotic diseases and normal wound healing, keloids exhibit little transformation of dermal fibroblasts into α-SMA⁺ myofibroblasts. This study showed that asporin is the most strongly expressed gene in keloids and its gene-ontology terms relate strongly to ECM metabolism/organization. Experiments with human dermal cells (HDFs) showed that asporin overexpression/treatment abrogated the HDF ability to adopt a perpendicular orientation when subjected to stretching tension. It also induced calcification of the surrounding 3D collagen matrix. Asporin overexpression/treatment also prevented the HDFs from remodeling the surrounding 3D collagen matrix, leading to a disorganized network of thick, wavy collagen fibers that resembled keloid collagen architecture. This in turn impaired the ability of the HDFs to contract the collagen matrix. Asporin treatment also made the fibroblasts impervious to the fibrous collagen contraction of α-SMA⁺ myofibroblasts, which normally activates fibroblasts. Thus, by calcifying collagen, asporin prevents fibroblasts from linearly rearranging the surrounding collagen; this reduces both their mechanosensitivity and mechanosignaling to each other through the collagen network. This blocks fibroblast activation and differentiation into the mature myofibroblasts that efficiently remodel the extracellular matrix. Consequently, the fibroblasts remain immature, highly proliferative, and continue laying down abundant extracellular matrix, causing keloid growth and invasion. Notably, dermal injection of asporin-overexpressing HDFs into murine wounds recapitulated keloid collagen histopathological characteristics. Thus, disrupted interfibroblast mechanocommunication may promote keloid progression. Asporin may be a new diagnostic biomarker and therapeutic target for keloids.

Mechanical and Immunological Regulation in Wound Healing and Skin Reconstruction

In the past decade, a new frontier in scarless wound healing has arisen because of significant advances in the field of wound healing realised by incorporating emerging concepts from mechanobiology and immunology. The complete integumentary organ system (IOS) regeneration and scarless wound healing mechanism, which occurs in specific species, body sites and developmental stages, clearly shows that mechanical stress signals and immune responses play important roles in determining the wound healing mode. Advances in tissue engineering technology have led to the production of novel human skin equivalents and organoids that reproduce cell–cell interactions with tissue-scale tensional homeostasis, and enable us to evaluate skin tissue morphology, functionality, drug response and wound healing. This breakthrough in tissue engineering has the potential to accelerate the understanding of wound healing control mechanisms through complex mechanobiological and immunological interactions. In this review, we present an overview of recent studies of biomechanical and immunological wound healing and tissue remodelling mechanisms through comparisons of species- and developmental stage-dependent wound healing mechanisms. We also discuss the possibility of elucidating the control mechanism of wound healing involving mechanobiological and immunological interaction by using next-generation human skin equivalents.

[Application of Zunyi's Suture Method for donor site of anterolateral thigh flap]

OBJECTIVE

To investigate the effectiveness of multiple tension reduction suture of in-situ return needle vertical mattress suture and in-situ return needle horizontal mattress suture combination with intradermal intermittent continuous suture (denominated as Zunyi's Suture Method) on suturing the donor site of the anterolateral thigh flap.

METHODS

Between January 2019 and December 2019, 62 patients were treated with anterolateral thigh flaps to repair wounds. There were 46 males and 16 females, aged 9-67 years (mean, 31 years). The size of anterolateral thigh flap ranged from 6 cm×5 cm to 25 cm×7 cm. The donor site of the flap was sutured directly by the Zunyi's Suture Method. The skin on both sides of the incision was advanced to the middle, and the wound edge was attached and in a state of negative tension. The intradermal suture line was removed at 7 days after operation. The complications and scars at donor site were observed during follow-up. The Vancouver Scar Scale was used to assess the appearance of scars and the width of scars were measured at 6 months after operation.

RESULTS

The flaps survived smoothly, and the wounds healed by first intention. The incisions at donor sites healed by first intention at 2 to 3 weeks after operation. All patients were followed up 7-16 months, with an average of 10.7 months. There was no ischemic necrosis of the donor site or skin threading. There was pigmentation of the needle back point in the early stage, and the pigmentation completely disappeared after 3 to 6 months without scar hyperplasia. At 6 months after operation, liner scars were achieved in all the patients with an average Vancouver Scar Scale score of 2.5 (range, 1.0-3.5) and an average width of 2.4 mm (range, 0.8-9.1 mm).

CONCLUSION

The suture of the donor site of the anterolateral thigh flap with Zunyi's Suture Method can effectively reduce the tension on wound edges and scar hyperplasia.

Management of keloid scars: noninvasive and invasive treatments

Scars vary from mature linear scars to abnormal excessive scars such as hypertrophic scars and keloid scars. Keloid scars are fibro-proliferative disease entities that reflect an abnormal process of wound healing. They can cause pain, itching, stiffness, and psychological distress, all of which can affect quality of life. Various treatment options have been advocated as ways to prevent and treat keloid scars. These include noninvasive treatments such as use of silicone gel sheeting and compression therapy, and invasive treatments such as intralesional corticosteroid injections, surgery, and radiotherapy. Novel treatments include chemotherapy, immunotherapy, and anti-inflammatory therapies. Unfortunately, keloids continue to pose a significant challenge due to the lack of efficacious treatments. Therefore, clinicians should be familiar with various therapeutic options and apply the most suitable treatment plan for patients. In this review, we introduce the current therapeutic options for the management of keloid scars.

New strategy of modulating incision tension: A wound tension offloading device applied before surgery

Wound tension plays a key role in the process of wound healing and scar formation. Tension offloading devices have been reported to reduce postsurgical scar formation. This study aims to determine whether the application of a tension offloading device preoperatively would result in superior attenuation of scar genesis in comparison to traditional methods. Randomized, controlled trials were performed on 12 patients, 4 patients were treated both preoperatively and postoperatively, while the other 4 were treated only postoperatively. The remaining 4 patients did not receive any sort of intervention. The overall performance was analyzed over 6 months period. The skin elasticity coefficient improved significantly with the application of a tension-offloading device. Compared with control group, patients who received treatment via the device displayed a better result in scar width and regression of color. It was also shown that the use of a device in the group with twin pre-op and post-op intervention resulted in a reduction of the wound healing period in comparison to the post-op group. Application of a tension-offloading device preoperatively can reduce tensile forces acting on the incision, thereby resulting in faster wound healing and enhanced efficacy on postsurgical reapplication. The effectiveness of the device in preventing hypertrophic scar is likely to be improved by long-term application after operation.

Mechanotransduction in Wound Healing: From the Cellular and Molecular Level to the Clinic

GENERAL PURPOSE

To review the various mechanical forces that affect fibroblasts, keratinocytes, endothelial cells, and adipocytes at the cellular and molecular level as well as scar-reducing mechanical devices currently in clinical use.

TARGET AUDIENCE

This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

LEARNING OBJECTIVES/OUTCOMES

After participating in this educational activity, the participant will:1. Compare and contrast the responses of various types of cells to mechanical forces.2. Identify the mechanical devices and techniques that can help restore skin integrity.

Keloidal pathophysiology: Current notions

INTRODUCTION

Keloids are pathological scars that are notorious for their chronic and relentless invasion into adjacent healthy skin, with commonly seen post-therapeutic recurrence after monotherapies.

METHODS

An English literature review on keloid pathophysiology was performed by searching the PubMed, Embase and Web of Science databases, to find out the up-to-date relevant articles. The level of evidence was evaluated based on the included studies with the highest level of evidence first.

RESULTS

Keloid morphology, signs, symptoms and the histopathological changes that occur in the local cells and extracellular matrix components are described. The theories on the pathophysiology of keloidogenesis that have been proposed to date are also covered; these include endocrinological, nutritional, vascular, and autoimmunological factors. In addition, we describe the local mechanical forces (and the mechanosignalling pathways by which these forces shape keloid cell activities) that promote keloid formation and determine the direction of invasion of keloids and the body sites that are prone to them.

CONCLUSION

A better understanding of this pathological entity, particularly its mechanobiology, will aid the development of new diagnostic and therapeutic strategies for use in the clinic to prevent, reduce or even reverse the growth of this pathological scar.

LAY SUMMARY

Keloids are skin scars that are famous for their chronic invasion into healthy skin, with commonly seen recurrence after surgeries. Cells such as lymphocytes, macrophages, mast cells and endothelial cells are involved in keloid growth. Particularly, endocrinological, nutritional, vascular, autoimmunological and mechanical factors actively take part in keloid progression.

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.

The effectiveness of the intramuscular quadratus lumborum block in postoperative analgesia after cesarean section with vertical incision: a randomized, double-blinded placebo-controlled study

PURPOSE

Quadratus lumborum block (QLB) has recently been used for postoperative analgesia after abdominal surgery. Although there are several approaches to QLB, the effectiveness of intramuscular QLB (QLBi) remains controversial. The aim of the present study was to examine the effectiveness of QLBi for postoperative analgesia after cesarean section with a vertical midline incision.

METHODS

In this single-center, randomized, double-blinded placebo-controlled study, 36 women who were scheduled for elective cesarean section were randomly divided into a QLBi group (n = 18) and a placebo group (n = 18). In both groups, spinal anesthesia was performed with 10-11 mg hyperbaric bupivacaine and 15 µg fentanyl. After the surgery, in the QLBi group, 0.4 mL/kg of 0.25% ropivacaine was injected into the bilateral quadratus lumborum muscle under ultrasound guidance (the total volume was 0.8 mL/kg). In the placebo group, instead of ropivacaine, the subjects were injected with the same amount of normal saline. The primary outcome measure was elapsed time to first analgesic use from the QLBi block after cesarean section.

RESULTS

The data from all 36 patients were analyzed. There were no significant differences between the QLBi and placebo groups regarding elapsed time to first postoperative analgesic use [mean 230 (standard deviation 103) vs 194 (89) min; 95% confidence interval - 101 to 30; p = 0.27].

CONCLUSIONS

QLBi with the concentration and amount of local anesthetic used in the present study was clinically slightly effective, and the effect was limited for postoperative analgesia after cesarean section.

Keloids: Current and emerging therapies

Keloids are pathological scars that grow over time and extend beyond the initial site of injury after impaired wound healing. These scars frequently recur and rarely regress. They are aesthetically disfiguring, can cause pain, itching, discomfort as well as psychological stress, often affecting quality of life. Many treatment modalities, including surgical and non-surgical, have been explored and have been reported to be beneficial; however, none have been absolutely satisfactory or optimal for the treatment of all keloid subtypes to date. This poses a major challenge to clinicians. Often, a combinational therapeutic approach appears to offer the best results with higher patient satisfaction compared to monotherapy. The aetiopathogenesis of keloids is not fully elucidated; however, with recent advances in molecular biology and genetics, insight is being gained on the complex process of scar formation and hence new therapeutic and management options for keloids. In this paper, we explore the literature and summarise the general concepts surrounding keloid development and review both current (corticosteroids, surgical excision, silicone-based products, pressure therapy, radiotherapy, cryotherapy, laser therapy, imiquimod and 5-fluorouracil) and emerging (stem cell therapy, mitomycin C, verapamil, interferons, bleomycin, botulinum toxin type A and angiotensin-converting enzyme inhibitors) treatments. Increased knowledge and understanding in this area may potentially lead to the discovery and development of novel therapeutic options that are more efficacious for all keloid types.

LAY SUMMARY

Keloids are problematic scars that are difficult to treat and manage. The aetiopathogenesis of keloids is not clear; however, recent advances in molecular biology and genetics are beginning to shed light on the underlying mechanisms implicated in keloid scar formation which will hopefully lead to the development of treatment options for all keloid types. This review summarises current and emerging therapies.

Diagnosis and Treatment of Keloids and Hypertrophic Scars-Japan Scar Workshop Consensus Document 2018

There has been a long-standing need for guidelines on the diagnosis and treatment of keloids and hypertrophic scars that are based on an understanding of the pathomechanisms that underlie these skin fibrotic diseases. This is particularly true for clinicians who deal with Asian and African patients because these ethnicities are highly prone to these diseases. By contrast, Caucasians are less likely to develop keloids and hypertrophic scars, and if they do, the scars tend not to be severe. This ethnic disparity also means that countries vary in terms of their differential diagnostic algorithms. The lack of clear treatment guidelines also means that primary care physicians are currently applying a hotchpotch of treatments, with uneven outcomes. To overcome these issues, the Japan Scar Workshop (JSW) has created a tool that allows clinicians to objectively diagnose and distinguish between keloids, hypertrophic scars, and mature scars. This tool is called the JSW Scar Scale (JSS) and it involves scoring the risk factors of the individual patients and the affected areas. The tool is simple and easy to use. As a result, even physicians who are not accustomed to keloids and hypertrophic scars can easily diagnose them and judge their severity. The JSW has also established a committee that, in cooperation with outside experts in various fields, has prepared a Consensus Document on keloid and hypertrophic scar treatment guidelines. These guidelines are simple and will allow even inexperienced clinicians to choose the most appropriate treatment strategy. The Consensus Document is provided in this article. It describes (1) the diagnostic algorithm for pathological scars and how to differentiate them from clinically similar benign and malignant tumors, (2) the general treatment algorithms for keloids and hypertrophic scars at different medical facilities, (3) the rationale behind each treatment for keloids and hypertrophic scars, and (4) the body site-specific treatment protocols for these scars. We believe that this Consensus Document will be helpful for physicians from all over the world who treat keloids and hypertrophic scars.

Z-plasty and Postoperative Radiotherapy for Upper-arm Keloids: An Analysis of 38 Patients

Therapies for upper arm keloids include surgical excision followed by postoperative radiotherapy, silicone tape stabilization, and steroid plaster. However, a universally accepted therapeutic strategy for upper-arm keloids is lacking.

Applying the Chinese Wood Joinery Mortise-and-Tenon Principle to Repair Widening Surface Scars

We applied the classical Chinese wood joinery mortise-and-tenon principle to repair widening surface scars caused by incision tension. Along the outer margin of surface scars, the top half of the scar tissue was cut and removed. The authors designed serial tenon structures on the retained dermal surface of the scar and a series of corresponding mortise structures in the dermal tissue on the opposite side of the incision. Finally, the mortise and tenon structures were integrated and sutured, resulting in tensionless closure. Thirty-two surface scars were repaired with this method. The follow-up time ranged from 6 to 24 months. The incisions healed in the form of fine linear scars. No widening scars were observed in this series. The proposed mortise-and-tenon scar repair technique can effectively reduce incision tension and thus reduce scar formation at the incision site. The authors recommend this technique as an alternative effective method for revising widening surface scars.

Geometric modeling and a retrospective cohort study on the usefulness of fascial tensile reductions in severe keloid surgery

BACKGROUND

Severe keloids are currently treated with surgical resection followed by radiation. Radiotherapy is essential for preventing recurrences. Fascia tensile reduction suturing may also prevent recurrence. We asked whether superficial fascia tensile reduction with or without deep fascia tensile reduction reduced skin mechanical tension and yielded good outcomes.

METHODS

Geometric modeling on 3-dimensional anatomic shapes assessed the effect of superficial fascia tensile reduction with or without deep fascia tensile reduction on skin tension. A retrospective cohort study was performed on patients with severe anterior-chest keloids with Japan Scar Workshop-scar scale classification score ≥ 16 who underwent resection plus fascia tensile reduction plus radiotherapy between 2011 and 2016 and were followed for >18 months. Patient characteristics and 18-month postoperative outcomes were examined. Postoperative outcome was defined as rates of keloid disappearance, improvement, and obvious recurrence.

RESULTS

Maximal mechanical forces placed on the dermis by dermal sutures, dermal sutures plus superficial fascia tensile reduction, and dermal sutures plus superficial fascia tensile reduction plus deep fascia tensile reduction were 4,700, 573, and 697 Pa, respectively. Adding deep fascia tensile reduction to superficial fascia tensile reduction decreased the force on the superficial fascia. Of 77 cohort patients, 27 and 50 underwent superficial fascia tensile reduction and superficial fascia tensile reduction plus deep fascia tensile reduction, respectively. Superficial fascia tensile reduction plus deep fascia tensile reduction patients underwent complete excision more often (60.0% vs 37.0%, P = .046). The groups did not differ in 18-month surgical outcome, including recurrence rate (P = .670).

CONCLUSION

Our 2003 study showed that in anterior-chest keloids, resection plus non-fascial suturing plus radiotherapy led to a 43.1% recurrence. Thus, fascia tensile reduction suturing helps reduce anterior-chest keloid recurrence to ∼5.2%. Superficial fascia tensile reduction plus deep fascia tensile reduction is suitable for relatively large keloids that require total resection. Deep fascia tensile reduction may facilitate superficial fascia tensile reduction but may only be useful when it is technically difficult to achieve reduction with superficial fascia tensile reduction alone.

The Interplay of Mechanical Stress, Strain, and Stiffness at the Keloid Periphery Correlates with Increased Caveolin-1/ROCK Signaling and Scar Progression

BACKGROUND

Fibroproliferative disorders result in excessive scar formation, are associated with high morbidity, and cost billions of dollars every year. Of these, keloid disease presents a particularly challenging clinical problem because the cutaneous scars progress beyond the original site of injury. Altered mechanotransduction has been implicated in keloid development, but the mechanisms governing scar progression into the surrounding tissue remain unknown. The role of mechanotransduction in keloids is further complicated by the differential mechanical properties of keloids and the surrounding skin.

METHODS

The authors used human mechanical testing, finite element modeling, and immunohistologic analyses of human specimens to clarify the complex interplay of mechanical stress, strain, and stiffness in keloid scar progression.

RESULTS

Changes in human position (i.e., standing, sitting, and supine) are correlated to dynamic changes in local stress/strain distribution, particularly in regions with a predilection for keloids. Keloids are composed of stiff tissue, which displays a fibrotic phenotype with relatively low proliferation. In contrast, the soft skin surrounding keloids is exposed to high mechanical strain that correlates with increased expression of the caveolin-1/rho signaling via rho kinase mechanotransduction pathway and elevated inflammation and proliferation, which may lead to keloid progression.

CONCLUSIONS

The authors conclude that changes in human position are strongly correlated with mechanical loading of the predilection sites, which leads to increased mechanical strain in the peripheral tissue surrounding keloids. Furthermore, increased mechanical strain in the peripheral tissue, which is the site of keloid progression, was correlated with aberrant expression of caveolin-1/ROCK signaling pathway. These findings suggest a novel mechanism for keloid progression.