Institute for Biomechanics, ETH Zurich, Zurich, Switzerland.
AnyBody Technology A/S, Aalborg, Denmark.
PLoS One. 2018 Sep 17;13(9):e0204109. doi: 10.1371/journal.pone.0204109. eCollection 2018.
Musculoskeletal models represent a powerful tool to gain knowledge on the internal forces acting at the joint level in a non-invasive way. However, these models can present some errors associated with the level of detail in their geometrical representation. For this reason, a thorough validation is necessary to prove the reliability of their predictions. This study documents the development of a generic musculoskeletal model and proposes a working logic and simulation techniques for identifying specific model features in need of refinement; as well as providing a quantitative validation for the prediction of hip contact forces (HCF). The model, implemented in the AnyBody Modeling System and based on the cadaveric dataset TLEM 2.0, was scaled to match the anthropometry of a patient fitted with an instrumented hip implant and to reproduce gait kinematics based on motion capture data. The relative contribution of individual muscle elements to the HCF and joint moments was analyzed to identify critical geometries, which were then compared to muscle magnetic resonance imaging (MRI) scans and, in case of inconsistencies, were modified to better match the volumetric scans. The predicted HCF showed good agreement with the overall trend and timing of the measured HCF from the instrumented prosthesis. The average root mean square error (RMSE), calculated for the total HCF was found to be 0.298BW. Refining the geometries of the muscles thus identified reduced RMSE on HCF magnitudes by 17% (from 0.359BW to 0.298*BW) over the whole gait cycle. The detailed study of individual muscle contributions to the HCF succeeded in identifying muscles with incorrect anatomy, which would have been difficult to intuitively identify otherwise. Despite a certain residual over-prediction of the final hip contact forces in the stance phase, a satisfactory level of geometrical accuracy of muscle paths has been achieved with the refinement of this model.
肌肉骨骼模型是一种强大的工具，可以以非侵入性的方式获得关节水平内部力的知识。然而，这些模型可能存在与几何表示细节水平相关的一些误差。因此，需要进行彻底的验证以证明其预测的可靠性。本研究记录了通用肌肉骨骼模型的开发，并提出了一种工作逻辑和模拟技术，用于确定需要改进的特定模型特征；并提供了髋关节接触力（HCF）预测的定量验证。该模型在 AnyBody 建模系统中实现，基于 TLEM 2.0 尸体数据集，经过缩放以匹配配备仪器化髋关节植入物的患者的人体测量，并根据运动捕捉数据再现运动学。分析了单个肌肉元素对 HCF 和关节力矩的相对贡献，以确定关键几何形状，然后将其与肌肉磁共振成像（MRI）扫描进行比较，如果存在不一致，则对其进行修改以更好地匹配容积扫描。预测的 HCF 与仪器化假体测量的 HCF 的整体趋势和时间吻合较好。对于总 HCF，计算得出的平均均方根误差（RMSE）为 0.298BW。对因此确定的肌肉几何形状进行细化，使 HCF 幅度的 RMSE 降低了 17%（从 0.359BW 降低到 0.298*BW），整个步态周期。对 HCF 中单个肌肉贡献的详细研究成功地确定了具有不正确解剖结构的肌肉，如果没有这种方法，这些肌肉很难直观地识别。尽管在站立阶段最终髋关节接触力的预测存在一定的剩余过度预测，但通过对该模型的细化，已经达到了肌肉路径几何精度的令人满意的水平。
