THE MECHANICS OF BRAIN INJURIES
THE MECHANICS OF BRAIN INJURIES
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DOI：
10.1093/oxfordjournals.bmb.a071895
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发表时间：
1945-01-01
影响因子：
6.7
通讯作者：
HOLBOURN, AHS
中科院分区：
文献类型：
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作者：
HOLBOURN, AHS
几乎所有关于暴力导致脑损伤机制的理论都有一定的道理（Jakob，1912; Sjovall，1943; Anzelius，1943），但在作者看来（Holbourn，1943; 1944 a），只有头骨弯曲、骨折和头部旋转（Goggio，1941）才是重要的。物理学家会把大多数理论家的相对失败归因于他们处理问题的错误方法，因为他们一开始就把注意力集中在一个特定的机制上（例如政变和对冲，或脑贫血的产生）。物理学家最初的假设是，大脑的损伤是大脑中每个点的运动、力和变形的直接或间接后果。运动、力和变形并不是相互独立的，所以用变形来表示一切就足够了。这些都是严格遵守牛顿运动定律，但与近似的构成和形状的头骨和大脑。因此，进一步的进展只能来自更好的近似。要考虑的力作为叠加原理的结果，在这个特殊的问题中，假设每一个原因产生它自己的独立伤害是合理正确的。这些原因可以被认为是（a）颅骨弯曲对大脑产生的力，（B）颅骨骨折或骨缝分离产生的力，（c）头部整体运动产生的力，即使颅骨变形也会存在。(c)可以细分为（cj）线性加速力、（cj）旋转加速力、（Cj）离心力、（cj）科里奥利力。其中（C1）和（C4）显然可以忽略不计。现在可以把每个无穷小元素由于（a，B，clr Ct）而产生的变形分析为两种且只有两种类型：（a）形状的变化，或变形，而体积没有变化（物理学家把这分析为一组剪切应变）;（P）体积的变化而没有变形，（a）极容易伤害有生命的物体（Holbourn，1944 B）或无生命的物体。(P)由于流体静压的增加而导致的体积减小（px）和由于流体静压的减小而导致的体积增大（P1）。常识表明，只要不引起血管长时间闭塞，（P）是无害的。它对周围神经的无害性已得到证实（Grundfest，1936）。(Pg)也是无害的，除非压力的降低足以引起气穴现象，即蒸汽或溶解气体的气泡的释放。
There is some truth in almost all the theories of the mechanisms of brain injuries due to violence (Jakob, 1912; Sjovall, 1943; Anzelius, 1943), but in the writer's view (Holbourn, 1943; 1944a) only skull-bending, fracture, and rotation (Goggio, 1941) of the head are important. The physicist would attribute the comparative failure of most of the theorists to their wrong method of approaching the problem, in that they began by fastening their attention on a particular mechanism (eg coup and contrecoup, or production of cerebral anaemia). The physicist's initial assumption is that damage to the brain is a consequence, direct or indirect, of the movements, forces and deformations at each point in the brain. The movements, forces and deformations arc not independent; so that it is sufficient to express everything in terms of deformations. These are worked out with strict adherence to Newton's laws of motion, but with approximations to the constitution and shape of skull and brain. Hence further advances can come only from making better approximations.The Forces to be Considered As a consequence of the principle of superposition, it is reasonably correct to assume in this particular problem that each cause produces its own independent injury. These causes may be regarded as (a) forces on the brain resulting from bending of the skull,(b) forces resulting from fracture of the skull or separation of sutures,(c) forces resulting from movement of the head as a whole and which would exist even if the skull were undeformable.(c) may be sub-divided into (cj) linear acceleration forces,(c,) rotational acceleration forces,(Cj) centrifugal forces,(cj) Coriolis forces. Of these (Cj) and (c4) are clearly negligible. Now it is allowable to analyse the deformations of each Infinitesimal element due to (a, b, clr Ct) into two and only two types (a) change of shape; or distortion, without change of volume (this is analysed by physicists into a set of shearstrains) and (P) a change in volume without distortion,(a) is extremely liable to injure animate (Holbourn, 1944b) or inanimate objects.(P) is of two kinds (px) decrease in volume due to increase of hydrostatic pressure and (P,) increase in volume due to decrease in hydrostatic pressure. Common sense suggests that (P^ is harmless provided it does not cause prolonged occlusion of blood vessels. Its harmlessness has been verified for peripheral nerves (Grundfest, 1936).(Pg) is also harmless unless the decrease in pressure is sufficient to cause cavitation, ie liberation of bubbles of vapour or dissolved gases.