Prange Michael T, Luck Jason F, Dibb Alan, Van Ee Chris A, Nightingale Roger W, Myers Barry S
Injury and Orthopaedic Biomechanics Laboratory, Duke University.
Stapp Car Crash J. 2004 Nov;48:279-99. doi: 10.4271/2004-22-0013.
The adult head has been studied extensively and computationally modeled for impact, however there have been few studies that attempt to quantify the mechanical properties of the pediatric skull. Likewise, little documentation of pediatric anthropometry exists. We hypothesize that the properties of the human pediatric skull differ from the human adult skull and exhibit viscoelastic structural properties. Quasi-static and dynamic compression tests were performed using the whole head of three human neonate specimens (ages 1 to 11 days old). Whole head compression tests were performed in a MTS servo-hydraulic actuator. Testing was conducted using nondestructive quasi-static, and constant velocity protocols in the anterior-posterior and right-left directions. In addition, the pediatric head specimens were dropped from 15cm and 30cm and impact force-time histories were measured for five different locations: vertex, occiput, forehead, right and left parietal region. The compression stiffness values increased with an increase in velocity but were not significantly different between the anterior-posterior and right-left directions. Peak head acceleration during the head impact tests did not significantly vary between the five different impact locations. A three parameter model that included damping represented the pediatric head impact data more accurately than a simple mass-spring system. The compressive and impact stiffness of the pediatric heads were significantly more compliant than published adult values. Also, infant head dimensions, center of gravity and moment of inertia (Iyy) were determined. The CRABI 6-month dummy impact response was similar to the infant cadaver for impacts to the vertex, occiput, and forehead but dramatically stiffer in lateral impacts. These pediatric head anthropomorphic, compression, and impact data will provide a basis to validate whole head models and compare with ATD performance in similar exposures.
成人头部已被广泛研究并建立了用于撞击的计算模型，然而，很少有研究试图量化小儿颅骨的力学性能。同样，关于小儿人体测量学的文献也很少。我们假设人类小儿颅骨的特性与成人颅骨不同，并具有粘弹性结构特性。使用三个人类新生儿标本（年龄为1至11天）的整个头部进行了准静态和动态压缩测试。在MTS伺服液压致动器中进行了整个头部的压缩测试。测试采用无损准静态和恒定速度协议，分别在前-后和右-左方向进行。此外，将小儿头部标本从15厘米和30厘米处掉落，并测量了五个不同位置（头顶、枕部、前额、右顶叶和左顶叶区域）的冲击力-时间历程。压缩刚度值随速度增加而增加，但在前-后和右-左方向之间没有显著差异。头部撞击测试期间的峰值头部加速度在五个不同撞击位置之间没有显著变化。一个包含阻尼的三参数模型比简单的质量-弹簧系统更准确地代表了小儿头部撞击数据。小儿头部的压缩和撞击刚度明显比已发表的成人值更柔顺。此外，还确定了婴儿头部尺寸、重心和转动惯量（Iyy）。CRABI 6个月假人的撞击响应在头顶、枕部和前额撞击时与婴儿尸体相似，但在侧面撞击时明显更硬。这些小儿头部人体测量、压缩和撞击数据将为验证整个头部模型以及与类似暴露情况下的ATD性能进行比较提供基础。
