Agnew Amanda M, Murach Michelle M, Dominguez Victoria M, Sreedhar Akshara, Misicka Elina, Harden Angela, Bolte John H, Kang Yun-Seok, Stammen Jason, Moorhouse Kevin
Injury Biomechanics Research Center, The Ohio State University.
National Highway Traffic Safety Administration, Vehicle Research and Test Center.
Stapp Car Crash J. 2018 Nov;62:119-192. doi: 10.4271/2018-22-0004.
Despite safety advances, thoracic injuries in motor vehicle crashes remain a significant source of morbidity and mortality, and rib fractures are the most prevalent of thoracic injuries. The objective of this study was to explore sources of variation in rib structural properties in order to identify sources of differential risk of rib fracture between vehicle occupants. A hierarchical model was employed to quantify the effects of demographic differences and rib geometry on structural properties including stiffness, force, displacement, and energy at failure and yield. Three-hundred forty-seven mid-level ribs from 182 individual anatomical donors were dynamically (~2 m/s) tested to failure in a simplified bending scenario mimicking a frontal thoracic impact. Individuals ranged in age from 4 - 108 years (mean 53 ± 23 years) and included 59 females and 123 males of diverse body sizes. Age, sex, body size, aBMD, whole rib geometry and cross-sectional geometry were explored as predictors of rib structural properties. Measures of cross-sectional rib size (Tt.Ar), bone quantity (Ct.Ar), and bone distribution (Z) generally explained more variation than any other predictors, and were further improved when normalized by rib length (e.g., robustness and WBSI). Cortical thickness (Ct.Th) was not found to be a useful predictor. Rib level predictors performed better than individual level predictors. These findings moderately explain differential risk for rib fracture and with additional exploration of the rib's role in thoracic response, may be able contribute to ATD and HBM development and alterations in addition to improvements to thoracic injury criteria and scaling methods.
尽管在安全方面取得了进展，但机动车碰撞中的胸部损伤仍然是发病和死亡的重要原因，而肋骨骨折是最常见的胸部损伤。本研究的目的是探索肋骨结构特性的变异来源，以确定车辆乘员肋骨骨折风险差异的来源。采用分层模型来量化人口统计学差异和肋骨几何形状对包括刚度、力、位移以及破坏和屈服时的能量等结构特性的影响。在模拟正面胸部撞击的简化弯曲场景中，对来自182个个体解剖捐赠者的347根中级肋骨进行动态（约2米/秒）测试直至破坏。个体年龄范围为4至108岁（平均53±23岁），包括59名女性和123名不同体型的男性。研究探讨了年龄、性别、体型、骨密度、整个肋骨几何形状和横截面几何形状作为肋骨结构特性的预测因素。横截面肋骨尺寸（Tt.Ar）、骨量（Ct.Ar）和骨分布（Z）的测量通常比任何其他预测因素能解释更多的变异，并且在通过肋骨长度进行归一化时（例如，稳健性和WBSI）会进一步改善。未发现皮质厚度（Ct.Th）是一个有用的预测因素。肋骨水平的预测因素比个体水平的预测因素表现更好。这些发现适度地解释了肋骨骨折的差异风险，并且随着对肋骨在胸部反应中作用的进一步探索，除了改进胸部损伤标准和缩放方法外，可能有助于推进ATD和HBM的发展及改进。
