Hernandez Fidel, Wu Lyndia C, Yip Michael C, Laksari Kaveh, Hoffman Andrew R, Lopez Jaime R, Grant Gerald A, Kleiven Svein, Camarillo David B
Department of Mechanical Engineering, Stanford University, Stanford, CA, USA.
Ann Biomed Eng. 2015 Aug;43(8):1918-34. doi: 10.1007/s10439-014-1212-4. Epub 2014 Dec 23.
This preliminary study investigated whether direct measurement of head rotation improves prediction of mild traumatic brain injury (mTBI). Although many studies have implicated rotation as a primary cause of mTBI, regulatory safety standards use 3 degree-of-freedom (3DOF) translation-only kinematic criteria to predict injury. Direct 6DOF measurements of human head rotation (3DOF) and translation (3DOF) have not been previously available to examine whether additional DOFs improve injury prediction. We measured head impacts in American football, boxing, and mixed martial arts using 6DOF instrumented mouthguards, and predicted clinician-diagnosed injury using 12 existing kinematic criteria and 6 existing brain finite element (FE) criteria. Among 513 measured impacts were the first two 6DOF measurements of clinically diagnosed mTBI. For this dataset, 6DOF criteria were the most predictive of injury, more than 3DOF translation-only and 3DOF rotation-only criteria. Peak principal strain in the corpus callosum, a 6DOF FE criteria, was the strongest predictor, followed by two criteria that included rotation measurements, peak rotational acceleration magnitude and Head Impact Power (HIP). These results suggest head rotation measurements may improve injury prediction. However, more 6DOF data is needed to confirm this evaluation of existing injury criteria, and to develop new criteria that considers directional sensitivity to injury.
这项初步研究调查了直接测量头部旋转是否能改善对轻度创伤性脑损伤（mTBI）的预测。尽管许多研究表明旋转是mTBI的主要原因，但监管安全标准使用仅包含3个自由度（3DOF）的平移运动学标准来预测损伤。此前无法获得人类头部旋转（3DOF）和平移（3DOF）的直接6自由度测量值，以检验额外的自由度是否能改善损伤预测。我们使用6自由度仪器化护齿测量了美式橄榄球、拳击和综合格斗中的头部撞击，并使用12种现有的运动学标准和6种现有的脑有限元（FE）标准预测临床诊断的损伤。在513次测量的撞击中，有前两次对临床诊断的mTBI的6自由度测量。对于该数据集，6自由度标准对损伤的预测性最强，超过了仅3自由度平移和仅3自由度旋转标准。胼胝体中的峰值主应变，一种6自由度FE标准，是最强的预测指标，其次是两个包括旋转测量的标准，峰值旋转加速度大小和头部撞击力（HIP）。这些结果表明头部旋转测量可能会改善损伤预测。然而，需要更多的6自由度数据来证实对现有损伤标准的这一评估，并制定考虑损伤方向敏感性的新标准。
