Abstract:
We consider a one-dimensional morphoelastic model describing post-burn scar contraction. Contraction can lead to a limited range of motion (contracture). Reported prevalence of burn scar contractures are 58.6% at 3-6 weeks and 20.9% at 12 months post-reconstructive surgery after burns. This model describes the displacement of the dermal layer of the skin and the development of the effective Eulerian strain in the tissue. Besides these components, the model also contains components that play a major role in the skin repair after trauma. These components are signaling molecules, fibroblasts, myofibroblasts, and collagen. We perform a sensitivity analysis for many parameters of the model and use the results for a feasibility study. In this study, we test whether the model is suitable for predicting the extent of contraction in different age groups. To this end, we conduct an extensive literature review to find parameter values. From the sensitivity analysis, we conclude that the most sensitive parameters are the equilibrium collagen concentration in the dermal layer, the apoptosis rate of fibroblasts and myofibroblasts, and the secretion rate of signaling molecules. Further, although we can use the model to simulate significant distinct contraction densities in different age groups, our results differ from what is seen in the clinic. This particularly concerns children and elderly patients. In children we see more intense contractures if the burn injury occurs near a joint, because the growth induces extra forces on the tissue. Elderly patients seem to suffer less from contractures, possibly because of excess skin.
摘要:
我们考虑描述烧伤后疤痕收缩的一维形态弹性模型。收缩可导致有限的运动范围(挛缩)。据报道,烧伤后3-6周时烧伤瘢痕挛缩的患病率为58.6%,12个月时为20.9%。该模型描述了皮肤真皮层的位移和组织中有效欧拉应变的发展。除了这些组件,该模型还包含在创伤后皮肤修复中起主要作用的成分。这些成分是信号分子,成纤维细胞,肌成纤维细胞,和胶原蛋白。我们对模型的许多参数进行了敏感性分析,并将结果用于可行性研究。在这项研究中,我们检验了该模型是否适合预测不同年龄组的收缩程度。为此,我们进行了大量的文献回顾,以找到参数值。从敏感性分析来看,我们得出结论,最敏感的参数是真皮层中的平衡胶原蛋白浓度,成纤维细胞和肌成纤维细胞的凋亡率,和信号分子的分泌速率。Further,尽管我们可以使用该模型来模拟不同年龄段的显着不同的收缩密度,我们的结果与诊所的结果不同.这尤其涉及儿童和老年患者。在儿童中,如果烧伤发生在关节附近,我们会看到更强烈的挛缩,因为生长会对组织产生额外的力。老年患者的挛缩似乎较少,可能是因为多余的皮肤。