Non-rigid modeling of the human musculoskeletal system

软组织有助于减弱撞击诱导力在人体内的传递。然而，大多数人体肌肉骨骼系统的生物力学模型没有考虑软组织效应。其中一个主要原因是，到目前为止，活体受试者中软组织和骨骼相互之间的运动特征基本上没有文献记载。对活体受试者的节段性软组织质量的准确估计也非常有限。这降低了任何为量化由于撞击而产生的软组织效应而开发的生物力学模型的准确性。因此，将改进对活体受试者软组织和骨量大小的估计(将纳入生物力学模型)。将基于简单分段人体测量学开发新的组织质量预测方程。并与双光子X射线吸收法(DXA)得到的节段质量估计值进行了验证。如果将特定于人的软组织和刚性组织质量估计值用于分析不同年龄和体型的活体受试者的撞击响应，则可以在生物力学模型保真度方面取得显著进展。此外，将使用粘弹性力学系统来模拟撞击后软组织和刚性组织的动态行为。还将建立腿部和足部的有限元模型，并进行对比测试。此外，局部肌肉疲劳对撞击后节段反应和肌肉僵硬的作用将继续下去有待评估。表面加速度计将提供通过身体节段和关节传递的力的大小的估计。软组织在减少潜在伤害力传递方面的效果将基于膝盖和肘关节等关节的模型输出来确定。节段响应变异性将通过研究反映真实的日常工作和体育活动的上肢和下肢影响来评估，这些影响可能导致受伤(例如，伸手摔倒，跑步时脚后跟着地)。

Soft tissues help to attenuate the transmission of impact induced forces through the body.  However, most biomechanical models of the human musculoskeletal system do not consider soft tissue effects.  One main reason for this is that the movement characteristics of soft tissues and bone relative to one another in living subjects are largely undocumented to date.  Accurate estimates of the masses of segment soft tissues for living subjects are also very limited.  This reduces the accuracy of any biomechanical model that is developed to quantify soft tissue effects as a result of impact.  Therefore, improved estimates of soft tissue and bone mass magnitudes in living subjects (to be incorporated in biomechanical models) will be obtained for the upper and lower extremities and trunk.  Tissue mass prediction equations will be developed based on simple segment anthropometrics, and validated against segment mass estimates obtained by Dual Photon X-ray Absorptiometry (DXA).  Considerable gains in biomechanical model fidelity could be realized if person-specific soft and rigid tissue mass estimates were utilized in the analysis of the impact response of living subjects of varying ages and body types.  The dynamic behaviour of the soft and rigid tissues following impact will be modeled using visco-elastic mechanical systems.  A finite element model of the leg and foot will also be developed and tested in comparison.  The role of local muscle fatigue on the segment response and muscle stiffness following impact will continue to be evaluated.  Surface accelerometry will provide estimates of the magnitudes of transmitted forces through body segments and joints.  The effects that soft tissues have on reducing the transmission of potentially injurious forces will be determined based on model outputs at joints such as the knee and elbow.  Segment response variability will be evaluated by studying upper and lower extremity impacts that reflect genuine every day work and sport activities that can result in injury (e.g. falling on an outstretched hand, heel landings during running).