Department of Biomedical Engineering, Wake Forest School of Medicine, Winston-Salem, NC,USA.
Department of Biomedical Engineering and Sciences, Virginia Tech-Wake Forest University, Winston-Salem, NC,USA.
J Appl Biomech. 2022 Apr 28;38(3):136-147. doi: 10.1123/jab.2021-0098. Print 2022 Jun 1.
Head impact exposure is often quantified using peak resultant kinematics. While kinematics describes the inertial response of the brain to impact, they do not fully capture the dynamic brain response. Strain, a measure of the tissue-level response of the brain, may be a better predictor of injury. In this study, kinematic and strain metrics were compared to contact characteristics in youth football. Players on 2 opposing teams were instrumented with head impact sensors to record impact kinematics. Video was collected to identify contact scenarios involving opposing instrumented players (ie, paired contact scenarios) and code contact characteristics (eg, player role, impact location). A previously validated, high-resolution brain finite element model, the atlas-based brain model, was used to simulate head impacts and calculate strain metrics. Fifty-two paired contact scenarios (n = 105 impacts) were evaluated. Lighter players tended to have greater biomechanical metrics compared to heavier players. Impacts to the top of the helmet were associated with lower strain metrics. Overall, strain was better correlated with rotational kinematics, suggesting these metrics may be better predictors of the tissue-level brain response than linear kinematics. Understanding the effect of contact characteristics on brain strain will inform future efforts to improve sport safety.
头部碰撞暴露通常使用峰值合成运动学来量化。虽然运动学描述了大脑对冲击的惯性反应，但它们并不能完全捕捉到大脑的动态反应。应变是大脑组织水平反应的度量，可能是损伤的更好预测指标。在这项研究中，运动学和应变指标与青年足球的接触特征进行了比较。两支对立球队的球员都配备了头部撞击传感器来记录撞击运动学。收集视频以识别涉及对立仪器化球员的接触情况（即配对接触情况）并对接触特征进行编码（例如，球员角色、撞击位置）。使用先前验证的高分辨率大脑有限元模型，基于图谱的大脑模型，模拟头部撞击并计算应变指标。评估了 52 个配对接触情况（n=105 次撞击）。与较重的球员相比，较轻的球员往往具有更大的生物力学指标。头盔顶部的撞击与较低的应变指标相关。总的来说，应变与旋转运动学的相关性更好，这表明这些指标可能比线性运动学更好地预测大脑组织水平的反应。了解接触特征对大脑应变的影响将为未来提高运动安全性的努力提供信息。
