A randomized, controlled trial to determine the efficacy of paper tape in preventing hypertrophic scar formation in surgical incisions that traverse Langer's skin tension lines

Background: How a scar is managed postoperatively influences Its cosmetic outcome. After Suture removal, scars are susceptible to skin tension, which may be the trigger for hypertrophic scarring. Paper tape to support the scar may reduce multidirectional forces and prevent hypertrophic scarring. Methods: Seventy patients who had under gone cesarean section at the Royal Brisbane and Women's Hospital were randomized to treatment and control groups. Patients in the control group received no postoperative intervention. Patients in the treatment group applied paper tape to their scars for 12 weeks. Scars were assessed at 6 weeks, 12 weeks, and 6 months after surgery using Ultrasound to measure intradermal scar volume. Scars were also assessed using the International Clinical Recommendations. Results: Paper tape significantly decreased scar volume by a mean of 0.16 cm(3), (95 percent confidence Interval, 0.00 to 0.29 cm(3)) At 12 weeks after surgery, 41 percent of the control group developed hypertrophic scars compared with none in the treatment group (exact test, p = 0.003). In the treatment group, one patient developed a hypertrophic scar and four developed stretched scars only after the tape was removed. The odds of developing a hypertrophic scar were 13.6 times greater in the control than in the treatment group (95 percent confidence interval, 3.6 to 66.9). Of the 70 patients randomized, 39 completed the study. Four patients in the treatment group developed a localized red rash beneath the tape. These reactions were minor and transient and resolved without medical intervention. Conclusions: The development of hypertrophic and stretched scars in the treatment group only after the tape was removed suggests that tension acting on a scar is die trigger for hypertrophic scarring. Paper tape is likely to be an effective modality for the prevention of hypertrophic scarring through its ability to eliminate scar tension.

Bioengineered Approaches to Prevent Hypertrophic Scar Contraction

Burn injuries in the United States account for over one million hospital admissions per year, with treatment estimated at four billion dollars. Of severe burn patients, 30-90% will develop hypertrophic scars (HSc). Current burn therapies rely upon the use of bioengineered skin equivalents (BSEs), which assist in wound healing but do not prevent HSc. HSc contraction occurs of 6-18 months and results in the formation of a fixed, inelastic skin deformity, with 60% of cases occurring across a joint. HSc contraction is characterized by abnormally high presence of contractile myofibroblasts which normally apoptose at the completion of the proliferative phase of wound healing. Additionally, clinical observation suggests that the likelihood of HSc is increased in injuries with a prolonged immune response. Given the pathogenesis of HSc, we hypothesize that BSEs should be designed with two key anti-scarring characterizes: (1) 3D architecture and surface chemistry to mitigate the inflammatory microenvironment and decrease myofibroblast transition; and (2) using materials which persist in the wound bed throughout the remodeling phase of repair. We employed electrospinning and 3D printing to generate scaffolds with well-controlled degradation rate, surface coatings, and 3D architecture to explore our hypothesis through four aims.

In the first aim, we evaluate the impact of elastomeric, randomly-oriented biostable polyurethane (PU) scaffold on HSc-related outcomes. In unwounded skin, native collagen is arranged randomly, elastin fibers are abundant, and myofibroblasts are absent. Conversely, in scar contractures, collagen is arranged in linear arrays and elastin fibers are few, while myofibroblast density is high. Randomly oriented collagen fibers native to the uninjured dermis encourage random cell alignment through contact guidance and do not transmit as much force as aligned collagen fibers. However, the linear ECM serves as a system for mechanotransduction between cells in a feed-forward mechanism, which perpetuates ECM remodeling and myofibroblast contraction. The electrospinning process allowed us to create scaffolds with randomly-oriented fibers that promote random collagen deposition and decrease myofibroblast formation. Compared to an in vitro HSc contraction model, fibroblast-seeded PU scaffolds significantly decreased matrix and myofibroblast formation. In a murine HSc model, collagen coated PU (ccPU) scaffolds significantly reduced HSc contraction as compared to untreated control wounds and wounds treated with the clinical standard of care. The data from this study suggest that electrospun ccPU scaffolds meet the requirements to mitigate HSc contraction including: reduction of in vitro HSc related outcomes, diminished scar stiffness, and reduced scar contraction. While clinical dogma suggests treating severe burn patients with rapidly biodegrading skin equivalents, these data suggest that a more long-term scaffold may possess merit in reducing HSc.

In the second aim, we further investigate the impact of scaffold longevity on HSc contraction by studying a degradable, elastomeric, randomly oriented, electrospun micro-fibrous scaffold fabricated from the copolymer poly(l-lactide-co-ε-caprolactone) (PLCL). PLCL scaffolds displayed appropriate elastomeric and tensile characteristics for implantation beneath a human skin graft. In vitro analysis using normal human dermal fibroblasts (NHDF) demonstrated that PLCL scaffolds decreased myofibroblast formation as compared to an in vitro HSc contraction model. Using our murine HSc contraction model, we found that HSc contraction was significantly greater in animals treated with standard of care, Integra, as compared to those treated with collagen coated-PLCL (ccPLCL) scaffolds at d 56 following implantation. Finally, wounds treated with ccPLCL were significantly less stiff than control wounds at d 56 in vivo. Together, these data further solidify our hypothesis that scaffolds which persist throughout the remodeling phase of repair represent a clinically translatable method to prevent HSc contraction.

In the third aim, we attempt to optimize cell-scaffold interactions by employing an anti-inflammatory coating on electrospun PLCL scaffolds. The anti-inflammatory sub-epidermal glycosaminoglycan, hyaluronic acid (HA) was used as a coating material for PLCL scaffolds to encourage a regenerative healing phenotype. To minimize local inflammation, an anti-TNFα monoclonal antibody (mAB) was conjugated to the HA backbone prior to PLCL coating. ELISA analysis confirmed mAB activity following conjugation to HA (HA+mAB), and following adsorption of HA+mAB to the PLCL backbone [(HA+mAB)PLCL]. Alican blue staining demonstrated thorough HA coating of PLCL scaffolds using pressure-driven adsorption. In vitro studies demonstrated that treatment with (HA+mAB)PLCL prevented downstream inflammatory events in mouse macrophages treated with soluble TNFα. In vivo studies using our murine HSc contraction model suggested positive impact of HA coating, which was partiall impeded by the inclusion of the TNFα mAB. Further characterization of the inflammatory microenvironment of our murine model is required prior to conclusions regarding the potential for anti-TNFα therapeutics for HSc. Together, our data demonstrate the development of a complex anti-inflammatory coating for PLCL scaffolds, and the potential impact of altering the ECM coating material on HSc contraction.

In the fourth aim, we investigate how scaffold design, specifically pore dimensions, can influence myofibroblast interactions and subsequent formation of OB-cadherin positive adherens junctions in vitro. We collaborated with Wake Forest University to produce 3D printed (3DP) scaffolds with well-controlled pore sizes we hypothesized that decreasing pore size would mitigate intra-cellular communication via OB-cadherin-positive adherens junctions. PU was 3D printed via pressure extrusion in basket-weave design with feature diameter of ~70 µm and pore sizes of 50, 100, or 150 µm. Tensile elastic moduli of 3DP scaffolds were similar to Integra; however, flexural moduli of 3DP were significantly greater than Integra. 3DP scaffolds demonstrated ~50% porosity. 24 h and 5 d western blot data demonstrated significant increases in OB-cadherin expression in 100 µm pores relative to 50 µm pores, suggesting that pore size may play a role in regulating cell-cell communication. To analyze the impact of pore size in these scaffolds on scarring in vivo, scaffolds were implanted beneath skin graft in a murine HSc model. While flexural stiffness resulted in graft necrosis by d 14, cellular and blood vessel integration into scaffolds was evident, suggesting potential for this design if employed in a less stiff material. In this study, we demonstrate for the first time that pore size alone impacts OB-cadherin protein expression in vitro, suggesting that pore size may play a role on adherens junction formation affiliated with the fibroblast-to-myofibroblast transition. Overall, this work introduces a new bioengineered scaffold design to both study the mechanism behind HSc and prevent the clinical burden of this contractile disease.

Together, these studies inform the field of critical design parameters in scaffold design for the prevention of HSc contraction. We propose that scaffold 3D architectural design, surface chemistry, and longevity can be employed as key design parameters during the development of next generation, low-cost scaffolds to mitigate post-burn hypertrophic scar contraction. The lessening of post-burn scarring and scar contraction would improve clinical practice by reducing medical expenditures, increasing patient survival, and dramatically improving quality of life for millions of patients worldwide.

Recombinant human endostatin reduces hypertrophic scar formation in rabbit ear model through down- regulation of VEGF and TIMP-1.

Background: Recombinant human endostatin (Endostar) has been widely used to suppress angiogenesis in carcinoma patients. Hypertrophic scar (HS) tissue, much like a carcinoma, is often associated with angiogenesis. However, there have been few studies conducted on the effects of Endostar on HS or its mechanism. Objective: This paper investigated the effects Endostar on the HS of rabbit ears and studied the effects of Endostar on VEGF and TIMP-1 expression. Methods: Sixteen New Zealand white rabbits were used to establish HS models. Then, rabbit ears containing HS were randomly assigned to either the Endostar group or the control group. The changes of appearance and histology were evaluated using the naked eye, hematoxylin eosin staining, and a scar elevation index. The VEGF and TIMP-1 expressions were detected by immunohistochemical staining, RT-PCR, and western blot. Results: The thickness of the connective tissue in the Endostar group were thinner, the numbers of micro vessels and fibroblasts were fewer, and the collagen fibers were smoother. Moreover, the mRNA and protein expressions of VEGF and TIMP-1 in the Endostar group were significantly lower than those in the control group. Conclusion: The results suggested that Endostar reduced the formation of HS by down-regulation of VEGF and TIMP-1 expressions.

Reinforced hydrogels for silicone copolymer delivery for scar remediation

Hypertrophic scars are formed by collagen overproduction in wounded areas and often occur in victims of severe burns. There are several methods for hypertrophic scar remediation and silicone gel therapy is one of the more successful methods. Research by others has shown that the activity of these gels may be due to migration of amphiphilic silicone oligomers from the gel and into the dermis, down-regulating production of collagen by fibroblasts. Normal silicone oil (PDMS) does not produce the same effect on fibroblasts. The main purpose of this project is the introduction of a particular amphiphilic silicone rake copolymer into an appropriate network which can absorb and release the silicone copolymer on the scarred area. Hydrogels are polymeric crosslinked networks which can swell in water or a drug solution, and gradually release the drug when applied to the skin. The application of gel enhances the effectiveness of the therapy, reduces the period of treatment and can be comfortable for patients to use. Polyethylene glycol (PEG) based networks have been applied in this research, because the amphiphilic silicone rake copolymer to be used as a therapy has polyethylene oxide (PEO) as a side chain. These PEO side chains have very similar chemical structure to a PEG gel chain so enhancing both the compatibility and the diffusion of the amphiphilic silicone rake copolymer into and out of the gel. Synthesis of PEG-based networks has been performed by two methods: in situ silsesquioxane formation as crosslink with a sol-gel reaction under different conditions and UV curing. PEG networks have low mechanical properties which is a fundamental limitation of the polymer backbone. For mechanical properties enhancement, composite networks were synthesized using nano-silica with different surface modification. The chemical structure of in situ silsesquioxane in the dry network has been examined by Solid State NMR, Differential Scanning Calorimetry (DSC) and swelling measurements in water. Mechanical properties of dry networks were tested by Dynamic Mechanical Thermal Analysis (DMTA) to determine modulus and interfacial interaction between silica and the network. In this way a family of self-reinforced networks has been produced that have been shown to absorb and deliver the active amphiphilic silicone- PEO rake copolymer.

Pre-clinical evaluation of amphiphilic silicone oligomers for scar remediation

The formation of hypertrophic scars is a frequent outcome of wound repair and often requires further therapy with treatments such as silicone gel sheets (SGS; Perkins et al., 1983). Although widely used, knowledge regarding SGS and their mechanism of action on hypertrophic scars is limited. Furthermore, SGS require consistent application for at least twelve hours a day for up to twelve consecutive months, beginning as soon as wound reepithelialisation has occurred. Preliminary research at QUT has shown that some species of silicone present in SGS have the ability to permeate into collagen gel skin mimetics upon exposure. An analogue of these species, GP226, was found to decrease both collagen synthesis and the total amount of collagen present following exposure to cultures of cells derived from hypertrophic scars. This silicone of interest was a crude mixture of silicone species, which resolved into five fractions of different molecular weight. These five fractions were found to have differing effects on collagen synthesis and cell viability following exposure to fibroblasts derived from hypertrophic scars (HSF), keloid scars (KF) and normal skin (nHSF and nKF). The research performed herein continues to further assess the potential of GP226 and its fractions for scar remediation by determining in more detail its effects on HSF, KF, nHSF, nKF and human keratinocytes (HK) in terms of cell viability and proliferation at various time points. Through these studies it was revealed that Fraction IV was the most active fraction as it induced a reduction in cell viability and proliferation most similar to that observed with GP226. Cells undergoing apoptosis were also detected in HSF cultures exposed to GP226 and Fraction IV using the Tunel assay (Roche). These investigations were difficult to pursue further as the fractionation process used for GP226 was labour-intensive and time inefficient. Therefore a number of silicones with similar structure to Fraction IV were synthesised and screened for their effect following application to HSF and nHSF. PDMS7-g-PEG7, a silicone-PEG copolymer of low molecular weight and low hydrophilic-lipophilic balance factor, was found to be the most effective at reducing cell proliferation and inducing apoptosis in cultures of HSF, nHSF and HK. Further studies investigated gene expression through microarray and superarray techniques and demonstrated that many genes are differentially expressed in HSF following treatment with GP226, Fraction IV and PDMS7-g-PEG7. In brief, it was demonstrated that genes for TGFβ1 and TNF are not differentially regulated while genes for AIFM2, IL8, NSMAF, SMAD7, TRAF3 and IGF2R show increased expression (>1.8 fold change) following treatment with PDMS7-g-PEG7. In addition, genes for αSMA, TRAF2, COL1A1 and COL3A1 have decreased expression (>-1.8 fold change) following treatment with GP226, Fraction IV and PDMS7-g-PEG7. The data obtained suggest that many different pathways related to apoptosis and collagen synthesis are affected in HSF following exposure to PDMS7-g-PEG7. The significance is that silicone-PEG copolymers, such as GP226, Fraction IV and PDMS7-g-PEG7, could potentially be a non-invasive substitute to apoptosis-inducing chemical agents that are currently used as scar treatments. It is anticipated that these findings will ultimately contribute to the development of a novel scar therapy with faster action and improved outcomes for patients suffering from hypertrophic scars.

A porcine deep dermal partial thickness burn model with hypertrophic scarring

We developed a reproducible model of deep dermal partial thickness burn injury in juvenile Large White pigs. The contact burn is created using water at 92 degrees C for 15s in a bottle with the bottom replaced with plastic wrap. The depth of injury was determined by a histopathologist who examined tissue sections 2 and 6 days after injury in a blinded manner. Upon creation, the circular wound area developed white eschar and a hyperaemic zone around the wound border. Animals were kept for 6 weeks or 99 days to examine the wound healing process. The wounds took between 3 and 5 weeks for complete re-epithelialisation. Most wounds developed contracted, purple, hypertrophic scars. On measurement, the thickness of the burned skin was approximately 1.8 times that of the control skin at week 6 and approximately 2.2 times thicker than control skin at 99 days after injury. We have developed various methods to assess healing wounds, including digital photographic analysis, depth of organising granulation tissue, immunohistochemistry, electron microscopy and tensiometry. Immunohistochemistry and electron microscopy showed that our porcine hypertrophic scar appears similar to human hypertrophic scarring. The development of this model allows us to test and compare different treatments on burn wounds.

The effect of amphiphilic siloxane oligomers on fibroblast and keratinocyte proliferation and apoptosis

The formation of hypertrophic scars is a frequent medical outcome of wound repair and often requires further therapy with treatments such as Silicone Gel Sheets (SGS) or apoptosis-inducing agents, including bleomycin. Although widely used, knowledge regarding SGS and their mode of action is limited. Preliminary research has shown that small amounts of amphiphilic silicone present in SGS have the ability to move into skin during treatment. We demonstrate herein that a commercially available analogue of these amphiphilic siloxane species, the rake copolymer GP226, decreases collagen synthesis upon exposure to cultures of fibroblasts derived from hypertrophic scars (HSF). By size exclusion chromatography, GP226 was found to be a mixture of siloxane species, containing five fractions of different molecular weight. By studies of collagen production, cell viability and proliferation, it was revealed that a low molecular weight fraction (fraction IV) was the most active, reducing the number of viable cells present following treatment and thereby reducing collagen production as a result. Upon exposure of fraction IV to human keratinocytes, viability and proliferation was also significantly affected. HSF undergoing apoptosis after application of fraction IV were also detected via real-time microscopy and by using the TUNEL assay. Taken together, these data suggests that these amphiphilic siloxanes could be potential non-invasive substitutes to apoptotic-inducing chemical agents that are currently used as scar treatments.

A new future for growth factor complexes as wound therapies?

Background: Topical administration of growth factors (GFs) has displayed some potential in wound healing, but variable efficacy, high doses and costs have hampered their implementation. Moreover, this approach ignores the fact that wound repair is driven by interactions between multiple GFs and extracellular matrix (ECM) proteins. The Problem: Deep dermal partial thickness burn (DDPTB) injuries are the most common burn presentation to pediatric hospitals and also represent the most difficult burn injury to manage clinically. DDPTB often repair with a hypertrophic scar. Wounds that close rapidly exhibit reduced scarring. Thus treatments that shorten the time taken to close DDTPB’s may coincidently reduce scarring. Basic/Clinical Science Advances: We have observed that multi-protein complexes comprised of IGF and IGF-binding proteins bound to the ECM protein vitronectin (VN) significantly enhance cellular functions relevant to wound repair in human skin keratinocytes. These responses require activation of both the IGF-1R and the VN-binding αv integrins. We have recently evaluated the wound healing potential of these GF:VN complexes in a porcine model of DDTPB injury. Clinical Care Relevance: This pilot study demonstrates that GF:VN complexes hold promise as a wound healing therapy. Enhanced healing responses were observed after treatment with nanogram doses of the GF:VN complexes in vitro and in vivo. Critically healing was achieved using substantially less GF than studies in which GFs alone have been used. Conclusion: These data suggest that coupling GFs to ECM proteins, such as VN, may ultimately prove to be an improved technique for the delivery of novel GF-based wound therapies.

An investigation into the effect of amphiphilic siloxane oligomers on dermal fibroblasts

This study investigates the effect of well-defined poly(dimethylsiloxane)-poly(ethylene glycol) (PDMS-PEG) ABA linear block co-oligomers on the proliferation of human dermal fibroblasts. The co-oligomers assessed ranged in molecular weight (MW) from 1335 to 5208 Da and hydrophilic-lipophilic balance (HLB) from 5.9 to 16.6 by varying the number of both PDMS and PEG units. In general, it was found that co-oligomers of low MW or intermediate hydrophilicity significantly reduced fibroblast proliferation. A linear relationship between down-regulation of fibroblast proliferation, and the ratio HLB/MW was observed at concentrations of 0.1 and 1.0 wt % of the oligomers. This enabled the structures with highest efficiency to be determined. These results suggest the possible use of the PEG-PDMS-PEG block co-oligomers as an alternative to silicone gels for hypertrophic scar remediation.

Mathematical investigation of the interactions between the inflammatory response and mechanical aspects of dermal wound repair

Dermal wound repair involves complex interactions between cells, cytokines and mechanics to close injuries to the skin. In particular, we investigate the contribution of fibroblasts, myofibroblasts, TGFβ, collagen and local tissue mechanics to wound repair in the human dermis. We develop a morphoelastic model where a realistic representation of tissue mechanics is key, and a fibrocontractive model that involves a reasonable approximation to the true kinetics of the important bioactive species. We use each of these descriptions to elucidate the mechanisms that generate pathologies such as hypertrophic scars, contractures and keloids. We find that for hypertrophic scar and contracture development, factors regulating the myofibroblast phenotype are critical, with heightened myofibroblast activation, reduced myofibroblast apoptosis or prolonged inflammation all predicted as mediators for scar hypertrophy and contractures. Prevention of these pathologies is predicted when myofibroblast apoptosis is induced, myofibroblast activation is blocked or TGFβ is neutralised. To investigate keloid invasion, we develop a caricature representation of the fibrocontractive model and find that TGFβ spread is the driving factor behind keloid growth. Blocking activation of TGFβ is found to cause keloid regression. Thus, we recommend myofibroblasts and TGFβ as targets for clinicians when developing intervention strategies for prevention and cure of fibrotic scars.

Avaliação do impacto da blefaroplastia superior na qualidade de vida utilizando questionário padronizado (Qblefaro): estudo piloto

FUNDAMENTOS: Há escassa literatura sobre a avaliação dos resultados cirúrgicos e do impacto da cirurgia de blefaroplastia superior na qualidade de vida dos pacientes. OBJETIVO: Avaliar o impacto na qualidade de vida dos pacientes submetidos à cirurgia de blefaroplastia superior. MÉTODOS: Estudo prospectivo com questionário padronizado, em mulheres adultas submetidas à blefaroplastia superior e avaliadas após 90 dias para estimativa do impacto cirúrgico na qualidade de vida e de complicações. RESULTADOS: Foram avaliadas 41 mulheres adultas saudáveis (idade mediana 53 anos) no período de junho de 2005 a março de 2006. O questionário apresentou alta consistência interna. O elemento de qualidade de vida de maior impacto na primeira semana foi relacionado à percepção da aparência física, e o de menor impacto foi relacionadoà convivência com as pessoas próximas. A cicatrização hipertrófica foi a principal complicação tardia. O grau de satisfação com a cirurgia relacionou-se significativamente com a ausência de efeitos indesejados (p<0,01). CONCLUSÕES: Os autores sugerem ferramenta consistente para avaliar o impacto dessa intervenção cirúrgica na qualidade de vida dos pacientes. Destacam ainda altos índices de satisfação dos pacientes com a blefaroplastia superior.

Avaliação biológica dos extratos obtidos das sementes de Vatairea guianensis (Aublet).

As plantas medicinais são ampla e culturalmente utilizadas de forma empírica na Amazônia no tratamento de diversas doenças. Grande parte dessas plantas ainda não foi investigada cientificamente sobretudo quanto aos aspectos relacionados as atividades biológicas. A espécie selecionada neste trabalho é Vatairea guianensis, utilizada na medicina tradicional para tratar infecções de pele como as micoses cutâneas. Este trabalho avaliou a atividade antibacteriana in vitro dos extratos hidroetanólico, henicosânico, clorofórmico e metanólico obtidos das sementes de Vatairea guianensis pelo método da microdiluição em caldo para obtenção da Concentração Inibitória Mínima (CIM) e Concentração Bactericida Mínima (CBM), frente a bactérias Gram-positivas (Staphylococus aureus e Enterecoccus faecalis) e Gram-negativas (Pseudomonas aeruginosa e Salmonella sp). Avaliou-se também a atividade cicatrizante sobre feridas cutâneas abertas em ratos pela aplicação tópica do extrato hidroetanólico, representados pelos grupos G1 controle positivo (fibrinase); G2 controle negativo (sol salina); e grupos experimentais, (G3 dose 500mg/kg; G4 250mg/kg; G5 100mg/kg) por sete dias e a toxicidade aguda por via oral. A análise histológica do processo cicatricial foi avaliada, por meio de técnica convencional incluindo coloração HE e Picrossírius para observação das características histomorfológicas da reação inflamatória e análise descritiva da deposição de colágeno,respectivamente. Todos os extratos demonstraram atividade antimicrobiana contra todos os microrganismos testados com CIM que variaram de 3,12μg/mL a 50μg/mL e CBM com valores 6,25μg/mL a 100μg/mL. A análise histológica mostrou que o extrato hidroetanólico diminuiu a intensidade da reação inflamatória nos grupos G3 e G1, estimulou a síntese de colágeno tipo III em G1, G3 e G4 e aumentou a síntese de colágeno em G2 e G5. O experimento com extrato hidroetanólico obtido das sementes de Vatairea guianensis pareceu retardar o processo cicatricial nas doses de 500 e 250mg/kg em feridas abertas o que pode ser um efeito positivo por impedir a formação de cicatriz hipertrófica, sugerindo assim um efeito modulatório por parte do extrato. A avaliação da toxicidade aguda em camundongos revelou que o extrato hidroetanólico apresentou baixa toxicidade por via oral.

Evaluación de las propiedades clinimétricas de la escala POSAS y su aplicación en pacientes de la Fundación del Quemado en Bogotá

•Objetivos: Se tradujo, adaptó y evaluaron las propiedades clinimétricas de la escala POSAS en pacientes con cicatrices hipertróficas (CHT) y queloides (CQ) cómo secuelas de quemadura, que fueron manejados con Z plastias en la Fundación del Quemado en Bogotá (Colombia), entre Junio de 2015 a Abril de 2016. •Métodos: Estudio de evaluación de las propiedades clinimétricas de una escala. Se hizo una traducción y adaptación transcultural siguiendo el método de traducción-retrotraducción. Se aplicó el instrumento adaptado a cincuenta y dos pacientes (n=52) antes y después de la intervención quirúrgica. Se evaluó la validez, confiabilidad, sensibilidad al cambio y la utilidad de la escala. •Resultados: Se hallaron diferencias significativas en los puntajes obtenidos del Observador y del Paciente, antes y después de la intervención quirúrgica (p<0.000); a excepción de prurito. La escala POSAS demostró ser altamente confiable para la Escala del Observador y del Paciente (α = 0.912 y 0.765). Hubo alta correlación en las evaluaciones de dos observadores para las variables ordinales de la Escala del Observador (r>0.6). La concordancia entre las evaluaciones de dos observadores para las variables categóricas de la Escala del Paciente fue buena para la evaluación antes de la intervención para pigmentación y relieve (κ>0.61). Se demostró que el instrumento es capaz de detectar cambios clínicos en el tiempo (p<0.0000), a excepción de prurito (p= 0.271). •Conclusiones: La escala POSAS demostró ser un instrumento válido, confiable y útil para evaluar la calidad de la cicatriz en pacientes con CHT y CQ cómo secuelas de quemadura.