骨质疏松性椎体骨折后局部应力分布的有限元研究

The effect of back extensor on osteoporosis refracture of vertebra body

目的研究骨质疏松性椎体骨折后椎体局部应力分布情况,解释再骨折发生的原理。方法获取健康老年女性胸腰段CT平扫数据,通过Mimics及Geomagic对胸腰段椎体进行三维实体化,并修饰模型,使之符合分析要求,导入有限元软件ANSYS分析,通过改变结构的物理属性设定,获得健康及退变腰椎在不同背部伸肌质量情况下的应力分布情况。结果背伸肌在理想状态下,能够将骨折后作用与腰1上表面的最大应力减小25%。结论背部伸肌能够维持脊柱正常力学结构平衡,其素质的提高能够更好的增加肌骨骼适应性,对于骨质疏松患者预防骨折和再骨折有着重要的意义。

Objective Observing the stress distribution situation after compression fracture of vertebra body. Methods The data of vertebral body was got from CT on one female patient,60 years old. We converted the 2D data of vertebral body to 3D model, decorate and furnish the model to accomodate the finite element software. After setting the parameter of the model, and loading different load situation, we got the final result of the distribution of compression fracture vertebra body. Results Under ideal muscle strength situation, the maximum stress on top surface of fractured vertebral body decreased about 25 % than degenerated muscle. Conclusions The strength of back muscle will keep the balance of the spine, improve the fitness of the muscle skeleton of spine and decrease the risk of vertebral body fracture.