糖尿病患者足底压力和鞋垫减压结构的有限元分析

Plantar Pressure and Offloading Insole Structure for Diabetic Patients:A Finite Element Analysis

目的分析糖尿病患者足底压力特征,设计鞋垫的减压结构,以降低足底软组织表面压力和内部应力。方法基于CT影像建立人体足部三维有限元模型。在糖尿病患者足底高压区设计孔结构。采用正交试验和有限元法,分析孔的直径、深度、间距对足底软组织表面压力和内部应力的影响,得到最优方案,分别用有限元法和实验法分析多孔鞋垫的减压效果。结果糖尿病患者足底压力峰值高于健康人。在跖骨区和跟骨区采用直径5 mm、深6 mm、间距2 mm的孔结构,降低软组织表面压力和内部应力的效果较好,行走过程中足趾区、跖骨区、中足区和跟骨区的压力峰值分别降低15.6%、45.6%、53.5%和10.1%。结论有限元分析有助于了解糖尿病患者足底软组织内部应力;多孔鞋垫能降低软组织表面压力和内部应力。

Objective To investigate the plantar pressure features of diabetic patients,and design the offloading structure of insole to reduce the plantar pressure and internal stress of the soft tissue.Methods A three-dimensional finite element model of foot was established based on CT images.Hole structure was designed in the high plantar pressure area of diabetic patients.The effects of diameter,depth and interval of holes on plantar pressure was analyzed through orthogonal test and finite element analysis,to obtain the optimal scheme;and the offloading effect was analyzed with finite element analysis and experiment.Results The peak plantar pressure was higher in diabetic patients than in healthy individuals.The holes with 5 mm diameter,6 mm depth and 2 mm interval in metatarsal and calcaneus regions might effectively reduce the plantar pressure and internal stress of soft tissue,which was 15.6%,45.6%,53.5%and 10.1%less of the peak plantar pressure on toes,metatarsal,midfoot and calcaneus area,respectively,compared to walking without insoles.Conclusion Finite element analysis is helpful to explore the internal stress of soft tissue in diabetic patients,and insole with hole structure can reduce the plantar pressure and internal stress of soft tissue.