Department of Mechanical Engineering, University of Utah, Salt Lake City, UT 84112.
J Biomech Eng. 2021 Jul 1;143(7). doi: 10.1115/1.4050460.
Skull fracture is a common finding for both accidental and abusive head trauma in infants and young children, and may provide important clues as to the energy and directionality of the event leading to the skull fracture. However, little is understood regarding the mechanics of skull fracture in the pediatric skull, and how accidental fall parameters contribute to skull fracture patterns. The objectives of this research were to utilize a newly developed linear elastic fracture mechanics finite element model of infant skull fracture to investigate the effect of impact angle and fall height on the predictions of skull fracture patterns in infants. Nine impact angles of right parietal bone impacts were simulated from three different heights onto a rigid plate. The average ± standard deviation of the distance between the impact location and fracture initiation site was 8.0 ± 5.9 mm. Impact angle significantly affected the fracture initiation site (p < 0.0001) and orientation (p < 0.0001). A 15 deg variation in impact angle changed the initiation site up to 47 mm. The orientation of the fracture pattern was dependent on the impact location and ran either horizontal or vertical toward the ossification center of the bone. Fall height significantly affected the fracture length (p = 0.0356). Specifically, at the same impact angle, a 0.3 m increase in fall height increased the skull fracture length by 21.39 ± 34.26 mm. These data indicate that environmental variability needs to be carefully considered when evaluating infant skull fracture patterns from low-height falls.
颅骨骨折是婴儿和幼儿意外和虐待性头部创伤的常见表现，可能为导致颅骨骨折的事件的能量和方向提供重要线索。然而，对于儿科颅骨中的颅骨骨折机制以及意外坠落参数如何导致颅骨骨折模式，人们知之甚少。本研究的目的是利用新开发的婴儿颅骨骨折线性弹性断裂力学有限元模型，研究冲击角度和坠落高度对婴儿颅骨骨折模式预测的影响。从三个不同高度模拟了 9 个右侧顶骨撞击的冲击角度到刚性板上。撞击位置和骨折起始位置之间的平均距离 ± 标准偏差为 8.0 ± 5.9 mm。冲击角度显着影响骨折起始位置（p < 0.0001）和方向（p < 0.0001）。冲击角度 15 度的变化会导致起始位置变化高达 47 mm。骨折模式的方向取决于撞击位置，并且要么向骨骼的骨化中心水平延伸，要么垂直延伸。坠落高度显着影响骨折长度（p = 0.0356）。具体来说，在相同的冲击角度下，坠落高度增加 0.3 m 会使颅骨骨折长度增加 21.39 ± 34.26 mm。这些数据表明，在评估来自低高度坠落的婴儿颅骨骨折模式时，需要仔细考虑环境变化。
