基于骨肌多体动力学前臂旋前旋后的有限元分析

Finite element analysis of forearm pronation and supination based on musculoskeletal dynamics of multibody

目的探讨前臂旋前旋后运动的肌力变化以及肱骨应力、位移的生物力学特性。方法根据Dicom数据在MIMICS中重建三维肱骨并在Hypermesh中划分网格和材料赋值。采用志愿者的身高、体重数据在AnyBody骨骼肌肉系统中建立个性化上肢的骨骼肌肉模型,模拟前臂旋前旋后运动,导出旋前旋后运动过程中的肌力等边界条件,将此数据作为肱骨有限元分析的边界条件。最后在Abauqus中行肱骨应力、位移大小的分析。结果前臂0°~90°旋前运动时主要是旋前圆肌、旋前方肌发挥作用,旋前圆肌约90°时肌肉力最大,旋前方肌约40°时肌肉力最大。当前臂0°~90°旋后运动时主要是旋后肌、肱二头肌发挥作用,二者肌肉力在旋后约90°时最大。旋前运动约90°时肱骨受到的应力、位移最大,而旋后运动约10°时肱骨受到的应力、位移最大。应力大致在肱骨中下1/3处集中,而位移集中在肱骨的中部及远端,且以肱骨远端最为明显。结论利用AnyBody骨骼肌肉系统成功模拟了前臂旋前旋后运动并与有限元分析联动,在肌力加载下分析肱骨应力、位移。肱骨中下段是骨折的好发部位。

Objective To investigate the changes of muscle force and the biomechanics of the humeralstress and displacement in the pronation and supination motions of the forearm.Methods A three-dimensional reconstruction of humerus was performed based on Dicom data by Mimics Mesh division and material assignment were carried out in Hypermesh.According to the height and weight of volunteers,the musculoskeletal model of volunteers'individualized upper limbs was established by AnyBody.The pronation and supination of forearm were simulated.The muscle force and constraint conditions during the motion were derived.The derived data were taken as the boundary conditions of finite element analysis.Finally,the analysis of the force and displacement of the humerus was performed by Abauqus.Results The forearm 0°-90°pronation motion mainly plays a role in pronator teres muscle and pronator quadratus muscle.The pronator teres and pronator quadratus muscle force is the largest when the pronator is about 90°and 40°,respectively.The forearm 0°-90°supination movement is mainly caused by the supinator and biceps muscles.The muscle force of the two groups is maximum at about 90°supinator.When the pronation motion is about 90°,the stress and displacement of the humerus are the largest;when the supination is about 10°,the stress and displacement of the humerus are the largest.The stress is concentrated approximately in the lower third of the humerus;the displacement is concentrated in the middle and distal ends of the humerus,and is most prominent at the distal end of the humerus.Conclusion Using AnyBody musculoskeletal system,the forearm pronation and supination motion is successfully simulated and synchronized by finite element analysis,the humeral stress and displacements are analyzed by loading,which shows the mid low part of humerus is the prone site of fracture.