Three-dimensional finite element modelling of skeletal muscles: Parameter identification, simulation and verification

由于大多数肌肉紧密地包裹在“肌肉包”中，它们在收缩时必须与周围的肌肉组织相互作用。为了更深入地了解在力产生和收缩速度前提下的肌肉包体，有必要对肌肉包体的结构、三维变形和动力发展进行研究。基于这个问题，这个项目在整个资助阶段的主要目标是开发一个三维肌肉模型，允许在肌肉收缩过程中对力的发展和三维变形进行现实的预测。这已经在兔的比目鱼肌（SOL）中实现了。在最后的资助阶段，开发的模型还将转移到兔的其他小腿肌肉（腓肠肌：GAS，足底肌：PLA），最终将合并成肌肉包模型（SOL， GAS， PLA）。因此，完成整个项目的最后阶段的目标是额外获取几何数据（腱膜定位，三维纤维分布），由于肌肉填充对肌肉结构的影响，其必要性已被证明。此外，将完成前一资助阶段的公开工作，以确定GAS和PLA的材料特性，以及数据评估和模型验证。由于耗时和有时意外的工作步骤（这是处理应用程序所必需的），这在以前资助的项目期间是不可能的。因此，在GAS和整个肌肉包的收缩过程中，仍有大量的、实验性的、三维肌肉表面数据需要评估。在最后一个资助阶段收集的数据将被纳入描述肌肉包的三维模型。因此，第一次有了一个肌肉包模型，可以处理关于肌肉、肌肉包和身体部分的功能和设计的选择问题。

As most muscles are tightly packed in ‘muscle-packages’, they have to interact with surrounding muscle tissue during contraction. In order to gain a deeper understanding of muscle packing under the premise of force generation and contraction velocity, it is necessary to study the architecture, the three-dimensional deformation and the power development of muscle packages.Based on this question, the main goal of this project throughout the entire funding phase is the development of a three-dimensional muscle model that allows realistic predictions of force development and three-dimensional deformation during muscle contractions. This was already achieved for the soleus muscle (SOL) of the rabbit. In this final funding phase, the developed model will also be transferred to other calf muscles of the rabbit (gastrocnemius muscle: GAS, plantaris muscle: PLA), which will ultimately be merged into a muscle package model (SOL, GAS, PLA).Thus, the goal of this final phase, which completes the overall project, is the additional acquisition of geometry data (aponeurosis localisation, three-dimensional fibre distributions) whose necessity has been proven due to the impact of muscle packing on muscle architecture. Further, open work from the previous funding phase for the characterisation of the material properties of GAS and PLA as well as for data evaluation and model validation shall be completed. Due to time-consuming and sometimes unexpected working steps (which were necessary for the processing of the application), this was not possible in the previously funded project period. Hence, there are extensive, experimental, three-dimensional muscle surface data during contraction for the GAS and the entire muscle package that still need to be evaluated.The data collected in this last funding phase will be incorporated into a three-dimensional model describing the muscle package. Thus, for the first time, a muscle package model is available, which enables the handling of selected questions on the function and the design of muscles, muscle packages and body segments.