Finite Element Analysis of the Distal Tibia and Fibula Stress and Displacement Change after Different Transtibial Amputation

SONG Dengxin; CAO Yun; HE Xiaowen; DING Xu; YI Chengla

Abstract：Animal models of two kinds of transtibial amputation were established—the traditional transtibial amputation model and transtibial osteomyoplastic amputation model.Two kinds of entity model and finite element model were established in Simpleware 6.0 and Abaqus 6.12 software.By simulating the physiological loading,the displacement and stress changes of tibia and fibula distal were calculated by finite element analysis.In the same load conditions,the maximum relative displacement between the tibia and fibula in transtibial osteomyoplastic amputation model was significantly reduced than in traditiona lamputation model when stump against buck-ling,extension,vertical load;the relative displacement in the tibiofibular joint in transtibial osteomyoplastic amputation model was signif-icantly reduced than in traditional amputation model when against buckling,extension,abduction load,while that was significantly in-creased than in traditional amputation model when against adduction load.When stump against buckling,extension,abduction,vertical and rotation load,fibular stress in transtibial osteomyoplastic amputation model was significantly increased,while the stress of tibiofibular joint in transtibial osteomyoplastic amputation model was significantly reduced.The endurance and stability of proximal tibiofibular joint was increased by fibula bone bridge in transtibial osteomyoplastic amputation,the instability of fibula was reduced when loaded.The technique of transtibial osteomyoplastic amputation has a better biomechanical effect.