Abstract The objective of this study was to develop a probabilistic representation of the hip capsule, which is calibrated to experimental capsular torque-rotation behavior and captures the observed variability for use in population-based studies. A finite element model of the hip capsule was developed with structures composed of a fiber-reinforced membrane, represented by 2D quadrilateral elements embedded with tension-only non-linear spring. An average capsule representation was developed by calibrating ligament properties (linear stiffness, reference strain) so that torque-rotation behavior matched mean cadaveric data. A probabilistic capsule was produced by determining the ligament property variability which represented ±2 SD measured in the experiment. Differences between experimental and model kinematics across all positions had RMS error of 4.7°. Output bounds from the optimized probabilistic capsule representation were consistent with ±2 SD of experimental data; the overall RMS error was 5.1°. This model can be employed in population-based finite element studies of THA to assess mechanics in realistic scenarios considering implant design, as well as surgical and patient factors.

中文翻译：

---

概率有限元髋关节囊表示的开发和校准

摘要 本研究的目的是开发髋关节囊的概率表示，该表示被校准为实验性关节囊扭矩-旋转行为，并捕捉观察到的变异性以用于基于人群的研究。使用由纤维增强膜组成的结构开发了髋关节囊的有限元模型，由嵌入仅受拉非线性弹簧的二维四边形单元表示。通过校准韧带特性（线性刚度、参考应变）来开发平均胶囊表示，以便扭矩-旋转行为与平均尸体数据相匹配。通过确定韧带特性变异性产生概率胶囊，该变异性代表实验中测量的±2 SD。所有位置的实验和模型运动学之间的差异具有 4.7° 的 RMS 误差。优化的概率胶囊表示的输出范围与实验数据的 ±2 SD 一致；总 RMS 误差为 5.1°。该模型可用于 THA 的基于群体的有限元研究，以评估考虑植入物设计以及手术和患者因素的现实场景中的力学。