基于软骨和韧带的全腕关节有限元模型建立和舟状骨生物力学研究

Scaphoid biomechanical study based on finite element analysis of human wrist joint including cartilage and ligament

目的通过基于CT扫描数据包含韧带和软骨的腕关节有限元模型构建、受力分析,在传统仅以骨为研究和建模对象的有限元领域做出突破,以期为后期开展全结构、多组织生物力学有限元分析的研究提供参考。方法应用Mimics、Geomagic Studio、Abaqus等软件,采用快速个体化建模方法对1名29岁成年健康男性志愿者的右侧尺桡骨远端至近端指骨的CT扫描数据进行快速建立模型,施加沿中指轴线的静力载荷和约束,观察米塞斯应力的分布情况、最大值及其所处部位。结果在100、300N压力下,最大应力分别为1.059×108和3.178×108 Pa,在不同应力载荷下,腕关节的最大应力值和最小应力值部位均相同。不同荷载状态下应力云图显示,舟状骨最大应力值出现在腰部区域,可明确解释临床工作中舟状骨骨折多见于腰部,并且有效验证了本模型的真实性和有效性。结论采用个体化建模方法可对腕关节整体结构模型进行运算分析,在模拟韧带结构和软骨结构的分析中,可采用简化的梁结构和相互作用对实现。

Objective To construct a finite element model of wrist ligaments and cartilage containing the image data based on CT construction and stress analysis, soas to make a breakthrough in the study on bone finite element modeling and to further study the whole structure and multi-organizational biomechanical finite element analysis. Methods Mimics, Geomagic Studio and Abaqus softwares were used for rapid individualized modeling in a 29-year-old adult healthy male volunteers. CT scan was performed from the right radius and ulna distal to the proximal phalanx when the middle finger static axial loads and constraints were given. Chamisesi stress distribution, maximum stress and the location where the maximum affected were observed. Results The maximum stress were 1. 059 × 108 Pa and 3. 178 × 108 Pa under 100 N and 300 N pressure, respectively. Under different stress loads, both maximum stress and minimum stress were located at the same parts of the wrist. Under different loading conditions, stress cloud showed scaphoid maximum stress appeared at waist area, which could clearly explain why scaiphoid fracture is more common in the waist in clinic, and effectively verify the authenticity and validity of the model. Conclusion The operation analysis of overall structure of the wrist joint can be achieved by individualized modeling. The analysis of simulation ligaments and cartilage structure can be used to simplify the interaction of the beam structure. （Shanghai Med J, 2014, 37： 602-605）