Soft tissues in the pelvic region - novel characterization of properties and modifiers, and their influence on musculoskeletal loading

在与跌倒相关的撞击过程中，组织损伤的风险与撞击载荷的大小和分布直接相关。虽然该领域普遍认识到软组织在骨盆外侧(即‘臀部’区)跌倒时对撞击动力学的重要影响，但关于这些组织的特征、修改它们的因素以及准确描述它们对撞击动力学的影响的算法的信息有限。因此，拟议的研究由四个相辅相成的“主题”组成，将对骨盆区域软组织的基本机械特性、其潜在的修饰物以及这些软组织如何影响负荷动态产生新的见解。主题1和2将使用新的超声成像技术来研究个人因素(例如性别、年龄、身体成分)如何影响骨盆软组织的厚度和机械特性。这将通过全面应用剪切波弹性成像和与压痕力-偏转轮廓同步的B型成像来实现。在主题3中，人类志愿者将被用来检查这些软组织特性对骨盆外侧撞击动力学的影响。具体地说，参与者将经历一系列的加载场景(静态卧倒到低能量跌倒)。应用于骨盆皮肤表面的冲击动力学将使用测力板和高速压力测量系统进行测量，我们将研究主题1和2中检查的软组织特性如何与冲击动力学相关。所有以前的成果将通过使用经过验证的机械髋关节撞击模拟器整合到主题4中。根据主题1-3中观察到的特性范围定制的代理软组织材料将用于制作多达100个代理软组织覆盖物。这些软组织被整合到髋关节撞击模拟器中，将经历一系列撞击能量的模拟侧向坠落。载荷传感系统将测量冲击动力学，包括最终传递到股骨下面的载荷。总而言之，拟议的研究计划将产生世界上最可靠的骨盆区域软组织特性的表征，以及这些组织在侧向撞击时对髋部区域施加的负荷的影响。除了改进横向冲击的数学和力学模型外，这项研究还将促进与行业合作伙伴的合作，以改进用于压疮和髋部骨折的基于工程的载荷衰减装置的设计。参与培训的学员将体验到一个公平、多样化和包容性的研究环境，该环境使用多学科方法，包括人体实验研究、新型成像技术、机械冲击模拟器和数学建模。这些新颖的技能组合将支持他们成为学术或行业未来的领导者。

During fall-related impacts, the risk of tissue damage is directly related to the magnitude and distribution of impact loads. While the field generally recognizes the important influence of soft tissues on impact dynamics during falls on the lateral pelvis (i.e. `hip' region), there is limited information about the characteristics of these tissues, the factors that modify them, and algorithms that accurately describe their influence on impact dynamics. Accordingly, the proposed research, comprised of four complementary `Themes', will generate novel insights into the basic mechanical properties of the soft tissues in the pelvic region, their underlying modifiers, and how these soft tissues influence loading dynamics. Themes 1 and 2 will use novel ultrasound imaging techniques to investigate how individual factors (e.g. sex, age, body composition) influence the thickness and mechanical properties of pelvic soft tissues. This will be accomplished through a comprehensive application of shear wave elastography, and B-mode imaging synchronized with indentation force-deflection profiling. In Theme 3, human volunteers will be used to examine the influence of these soft tissue properties on lateral pelvis impact dynamics. Specifically, participants will undergo a series of loading scenarios (static lying to low energy falls). Impact kinetics applied to the pelvic skin surface will be measured with force plates and high-speed pressure measurement systems, and we will examine how the soft tissue properties examined in Themes 1 and 2 relate to impact dynamics. All previous outcomes will be integrated in Theme 4 through the use a validated mechanical hip impact simulator. Surrogate soft tissue materials, custom-made to match the range of properties observed in Themes 1-3, will be used to create up to 100 surrogate soft tissue coverings. These soft tissues, incorporated into the hip impact simulator, will undergo simulated sideways falls with a range of impact energies. Load sensing systems will measure impact kinetics, including the loads ultimately transmitted to the underlying femur. In summary, the proposed program of research will produce the world's most robust characterization of soft tissue properties in the pelvic region, in addition to the influence of these tissues on the loads applied to the hip region during lateral impacts. In addition to improving mathematical and mechanical models of lateral impact, this research will catalyze collaborations with industry partners to improve the design of engineering-based load attenuation devices for pressure sores and hip fractures. The trainees involved will experience an equitable, diverse, and inclusive research environment that uses multi-disciplinary approaches including experimental studies with humans, novel imaging technology, mechanical impact simulators, and mathematical modeling. These novel skill-sets will support their emergence as future leaders in academic or industry settings.