胸部撞击时胸壁的动力学响应与胸部损伤

目的：探讨胸部准静态撞击时胸壁动力学响应过程及其与损伤的关系。方法：在犬胸壁肋骨、胸骨等部位布放加速度传感器，监测胸壁运动过程，结合撞击物理参数分析胸壁的动力学响应与损伤的关系。结果：胸壁的粘性标准是预测胸部伤情的可靠参数，变形量、压缩响应和变形速度与损伤程度有一定的相关性，当撞击速度较低而变形量较大时，损伤形式演变成“挤压型”；当撞击速度高而变形量较低时，则演变为“冲击型”损伤。撞击能量、速度和撞击力对损伤的预测是间接的，机体结构和生物力学特性上的差异影响了它们间的相关性。高速撞击时损伤的防护应以减小变形速度为主，选择一种能降低体壁运动加速度和变形速度的材料对损伤的防护是有益的。结论：胸壁的变形运动过程是影响胸部损伤的关键，粘性标准是预测胸部伤情的可靠参数。

Dynamic response of chest wall and thoracic injuries during chest impact

Objective :To explore the dynamic response of chest wall and its relationship with the injury severity during static chest impact. Methods :Accelerometers were fixed on the ribs,sternum,and other areas to record the movement of chest wall in dogs,which were subjected to chest impact at velocity from 714 m/s to 1905 m/s.Combined with impact parameters,the relationship between the dynamic response and injury severity was analyzed. Results :Viscous criterion was the best parameter indicating the injury severity.Deformation,compression response and deformation speed were correlated with injury severity in some degrees.A crushing type injury would occur when the impact velocity was low enough and the compression response large.On the contrary,the blast type injury would appear when the impact velocity was high and the compression response was small enough.Impact energy,velocity and force only reflected the injury severity indirectly due to the difference of structure and biomechanics characteristics beteween different organs.Efforts should be made to reduce the deformation speed in the prevention of injuries caused by high velocity impact.A kind of material,which could decrease the movement acceleration and deformation speed,was helpful for the injury prevention. Conclusions :The movement of chest wall appears to be the major factor conflicting the thoracic injuries.Viscous criterion may be the valid parameter indicating the injury severity.