动力性胸腰保护器对中上胸椎保护的有限元研究

Infinite element study of dynamic thoracic waist protector for intermedial and upper thoracic verbetrae

[目的]通过建立有限元模型,研究垂直坠地时中上胸椎（T1-7）在动力性胸腰保护器（简称胸腰护具）保护下所受的应力变化,评价其对中上胸椎（T1-7）的保护作用。[方法]根据中国力学可视人数据库,构建了加载胸腰护具与否的两组人体躯干部有限元模型,第一组模型没有加载胸腰护具,第二组模型加载胸腰护具,通过其垂直坠地与仿真地面的撞击试验,比较两组模型中上胸椎（T1-7）椎体上所受的应力,并进行统计学分析。[结果]在第二组模型中中上胸椎（T1-7）受到的应力比第一组明显减少,两组胸椎所受的最大应力经配对设计t检验,P〈0.05,存在统计学意义。在第二组模型中加载护具的两侧肩带和腰围部所受的应力出现集中。[结论]胸腰护具可以明显减少垂直坠地时T1-7椎体所受的应力,具有预防老年人跌倒性中上胸椎骨折的作用。

[Objective]To evaluate the stress variation of intermedial and upper thoracic vertebrae（1-7） and the effect of dynamic thoracic waist protector during vertical fall with the protector based on finite element model.[Method]Two groups of finite element models were estabilished.The simulation model of trunk of human body impacted the simulation floor during vertical fall.Dynamic thoracic waist protector was not loaded in the first group but loaded in the second group.The maximal stress of thoracic vertebrae（1-7） were compared between the two groups with statistics.[Result]It was found that the stress of thoracic vertebrae（1-7） in the second group were obviously decreased.There were statistic significance between groups in the t-test of match-paired design（P〈0.05）.Stresses concentrated on the shoulder girdle and waist of the simulation protector.[Conclusion]The stress of intermedial and upper thoracic vertebrac（1-7） was obviously decreased during vertical fall with the dynamic thoracic waist protector.The protector can prevent fracture of thoracic vertebrae（1-7） in the elderly.