Hernández Ivonne A, Fyfe Ken R, Heo Giseon, Major Paul W
Faculty of Medicine and Dentistry, Department of Dentistry, University of Alberta, Room 4051b, Dentistry/Pharmacy Centre, Edmonton, AB, Canada T6G 2N8.
Clin Biomech (Bristol). 2005 Dec;20(10):1011-8. doi: 10.1016/j.clinbiomech.2005.07.002. Epub 2005 Sep 13.
To evaluate kinematics of head movement related to impact velocity, gender and awareness in simulated low velocity rear-end impacts.
Thirty individuals were subjected in random order to three rear-end impacts: two unexpected impacts causing chair acceleration of 4.5m/s2 (slow) and 10.0m/s2 (fast) and one 10.0m/s2 expected impact. Rearward head displacement, and linear and angular head accelerations were recorded.
Angular head displacement was almost two times higher for the fast than the slow unexpected-impacts (P=0.04). Rearward and forward angular head accelerations increased two to three times with increased impact magnitude (P<0.05). Rearward and forward linear head accelerations were two and a half to three and a half times higher for the fast than for the slow unexpected impacts (P<0.05). Males presented two times higher upward linear head acceleration than females in the unexpected fast impact. No significant magnitude differences were identified for impact awareness in kinematics of head movement (P>0.05). Rearward angular head acceleration reached the peak between 62 and 84 ms later than the rearward linear head acceleration (P<0.05) in all impacts. No significant differences were identified for timing of kinematics of head movement (P>0.05) with increased impact magnitude; however, statistical powers were low.
Kinematics of head movement increases with increased impact magnitude. Gender differences exist for vertical linear head acceleration only. Temporal and amplitude awareness do not change the magnitude in kinematics of head movement. There are temporal differences between angular and linear head accelerations.
评估在模拟的低速追尾碰撞中，与碰撞速度、性别和意识相关的头部运动学特征。
30名受试者按随机顺序接受三次追尾碰撞：两次意外碰撞，导致座椅加速度分别为4.5m/s²（慢速）和10.0m/s²（快速），以及一次预期的10.0m/s²碰撞。记录头部向后位移、头部线性加速度和角加速度。
快速意外碰撞时的头部角位移几乎是慢速意外碰撞时的两倍（P = 0.04）。随着碰撞强度增加，头部向后和向前的角加速度增加了两到三倍（P < 0.05）。快速意外碰撞时的头部向后和向前线性加速度比慢速意外碰撞时高2.5到3.5倍（P < 0.05）。在意外快速碰撞中，男性向上的头部线性加速度比女性高两倍。在头部运动学中，碰撞意识在运动学上没有显著的大小差异（P > 0.05）。在所有碰撞中，头部向后角加速度达到峰值的时间比头部向后线性加速度晚62至84毫秒（P < 0.05）。随着碰撞强度增加，头部运动学的时间没有显著差异（P > 0.05）；然而，统计功效较低。
头部运动学特征随碰撞强度增加而增加。仅在垂直线性头部加速度方面存在性别差异。时间和幅度意识不会改变头部运动学的大小。头部角加速度和线性加速度之间存在时间差异。
