TENDON FIBER-MATRIX MECHANICS--THEORY AND EXPERIMENTS

描述(摘自申请表)：受伤和修复的肌腱和 重建的韧带具有受损的机械性能。他们失去了一半的 他们的强度和僵硬，这可能会导致再次受伤或长期关节 有问题。肌腱力学性能下降的原因主要是 未知，但可能与肌腱机械完整性的破坏有关 微观结构，如纤维、基质或纤维与基质的相互作用。连 在正常的未受损肌腱中，对肌腱的力学作用知之甚少。 这些微结构。在这项研究中，假设机械 肌腱微结构对纤维、基质和纤维基质的贡献 相互作用在正常的肌腱行为中是重要的。在当前 建议书、材料建模和拉伸测试的工程工具 用来检验这一假说。在直接测量肌腱微结构时 显然是有价值的，我们的方法是从表示这些 数学模型中的微结构，并添加有针对性的生化和 后续研究中的微观结构措施。以下是具体目标 将会完成。在具体目标中，将展示1肌腱的微结构 在材质模型中。我们以前曾表示过 材料模型中的脊柱纤维环，这导致了新的 对纤维-基质相互作用在该组织中的作用的洞察。在 模型中，将使用结构张量来数学地表示肌腱 各向同性基质中的纤维。在具体目标2中，机械贡献 肌腱微结构的强度将在拉伸试验中进行测量。最后，在 具体目标3将通过预测来验证模型是否适用于复杂载荷 直接测量双向拉伸时的应力应变行为。通过 量化这些微结构在正常情况下的力学贡献 肌腱，我们不仅可以了解正常的肌腱功能，还可以 生成基线信息，以研究地点和方式等问题 肌腱的力学性能在肌腱修复或韧带修复后受损 免费的。这些信息将使我们能够开发和评估潜力 治疗方式。

DESCRIPTION (Taken from the application): Injured and repaired tendons and reconstructed ligaments have impaired mechanical properties. They lose half of their strength and stiffness, which may lead to re-injury or to long-term joint problems. The causes of the decreased tendon mechanical properties are largely unknown, but may be related to disruption in the mechanical integrity of tendon micro-structures such as the fibers, matrix or fiber-matrix interactions. Even in normal undamaged tendon, little is known of the mechanical contributions of these micro-structures. In this study, it is hypothesized that the mechanical contributions of the tendon micro-structures of fiber, matrix, and fiber-matrix interactions are significant in normal tendon behavior. In the current proposal, engineering tools of material modeling and tensile testing will be used to test this hypothesis. While directly measuring tendon micro-structure is clearly valuable, our approach is to begin by representing these micro-structures in a mathematical model and to add targeted biochemical and micro-structural measures in subsequent studies. The following specific aims will be completed. In Specific Aim 1 tendon micro-structure will be represented in a material model. We have previously represented the micro-structure of the anulus fibrosus of the spine in a material model, which resulted in new insights into the role of fiber-matrix interactions in that tissue. In the model, structural tensors will be used to mathematically represent the tendon fiber within an isotropic matrix. In Specific Aim 2 the mechanical contribution of tendon micro-structures will be measured in tensile tests. Finally, in Specific Aim 3 the model will be validated for complex loading by predicting and directly measuring the stress-strain behaviors in biaxial tension. By quantifying the mechanical contributions of these micro-structures in normal tendon, we will not only obtain insight into normal tendon function, but also generate baseline information from which to study questions of where and how tendon mechanical properties are impaired following tendon repairs or ligament gratis. This information will enable us to develop and assess potential treatment modalities.