Hitosugi Masahito, Murayama Haruo, Motozawa Yasuki, Ishii Kanto, Ogino Masahiro, Koyama Katsuhiro
Department of Legal Medicine, Shiga University of Medical Science.
Biomed Res. 2014;35(5):339-44. doi: 10.2220/biomedres.35.339.
This study investigated biomechanical mechanisms of acute subdural hematoma caused by judo and sought preventive measures to reduce injury. A Japanese judo expert repeatedly threw an anthropometric test device using two throwing techniques, Osoto-gari and Ouchi-gari. Linear and angular accelerations of the head were measured. Both throwing techniques resulted in the dummy falling backwards, with the occipital area of the head contacting the mat, and peak linear and angular accelerations being observed when the head contacted the mat. For linear acceleration, the posterior-anterior direction showed the greatest force (41.0 ± 2.6 G using Osoto-gari, and 86.5 ±4.3 G using Ouchi-gari). For angular acceleration, values for sagittal plane rotation were greatest among the three directions measured (3315 ± 168 rad/s(2) using Osoto-gari, and 1328 ± 201 rad/s(2) using Ouchi-gari). We concluded that occipital head contact produced the most forceful longitudinal linear and sagittal plane angular accelerations; subsequent stretches and ruptures of parasagittal bridging veins resulting in acute subdural hematoma. As severe head injuries can result if a person's head comes into contact with the mat, offensive throwing techniques should be restricted to participants able to sufficiently demonstrate the Ukemi technique.
本研究调查了柔道所致急性硬膜下血肿的生物力学机制，并寻求预防损伤的措施。一名日本柔道专家使用大内刈和小内刈两种投技反复投掷一个人体测量测试装置。测量了头部的线性加速度和角加速度。两种投技都导致假人向后摔倒，头部枕部与垫子接触，并且当头部接触垫子时观察到线性加速度和角加速度的峰值。对于线性加速度，前后方向显示出最大的力（大内刈为41.0±2.6G，小内刈为86.5±4.3G）。对于角加速度，在测量的三个方向中矢状面旋转的值最大（大内刈为3315±168rad/s²，小内刈为1328±201rad/s²）。我们得出结论，枕部头部接触产生了最强烈的纵向线性加速度和矢状面角加速度；随后矢状窦旁桥静脉的拉伸和破裂导致急性硬膜下血肿。由于如果人的头部与垫子接触可能会导致严重的头部损伤，攻击性投技应仅限于能够充分展示受身技术的参与者。
