Non-rigid modeling of the human musculoskeletal system

软组织有助于减弱冲击力通过身体的传递。 然而，大多数人体肌肉骨骼系统的生物力学模型不考虑软组织的影响。 一个主要的原因是，软组织和骨相对于彼此在活体对象的运动特性，在很大程度上是没有记录的日期。 活体段软组织质量的准确估计也非常有限。 这降低了任何生物力学模型的准确性，该模型被开发用于量化由于撞击而产生的软组织效应。 因此，将获得活体受试者的软组织和骨量大小的改进估计值（将纳入生物力学模型），用于上肢和下肢以及躯干。 将基于简单的节段人体测量学开发组织质量预测方程，并根据双光子X射线吸收测定法（DXA）获得的节段质量估计值进行验证。 生物力学模型的保真度可以实现相当大的收益，如果人特定的软组织和刚性组织质量的估计被用于分析不同年龄和身体类型的活体受试者的冲击响应。 软组织和刚性组织的动态行为的影响将使用粘弹性力学系统建模。 还将开发腿部和足部的有限元模型并进行比较测试。 将继续评估局部肌肉疲劳对撞击后节段反应和肌肉僵硬的作用。 表面加速度测量将提供通过身体部分和关节传递的力的大小的估计。 将根据膝关节和肘关节的模型输出确定软组织对减少潜在伤害力传递的影响。 将通过研究上肢和下肢冲击来评价节段反应变异性，这些冲击反映了可能导致受伤的日常工作和体育活动（例如，摔倒在伸出的手上，跑步期间脚跟着地）。

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).