新型跟骨外固定支架治疗SandersⅢAB型跟骨骨折的有限元分析

Finite element analysis of the treatment of Sanders typeⅢAB calcaneal fractures with a new type of calcaneal external fixation

目的应用有限元分析方法,比较一种新型外固定支架与钢板在治疗SandersⅢAB型跟骨骨折的应力分布及生物力学的稳定性。方法获取一位正常成人踝及跟骨CT图像,应用软件构建跟骨SandersⅢAB型骨折模型及其外固定模型、钢板模型,经材料赋值及力学加载,记录各模型的骨折块位移情况,并分析其应力分布情况。结果模型载荷加载后,钢板模型中,钢板及螺钉位移峰值为0.13 mm,跟骨骨块位移峰值为0.26 mm;钢板及螺钉应力峰值为281.10 MPa,跟骨骨块应力峰值为297.40 MPa。外固定模型中,外支架位移峰值为0.17 mm,跟骨骨块位移峰值为0.27 mm;外固定及克氏针应力峰值为125.40 MPa,跟骨骨块应力峰值为38.13 MPa。结论该新型外固定支架在治疗SandersⅢAB型骨折时,固定牢靠、有效,能提供足够的生物力学稳定性,为跟骨骨折的治疗提供了新思路。

Objective To compare the stress distribution and biomechanical stability of a new type of external fixator and locking plate in the treatment of Sanders typeⅢAB calcaneal fracture by finite element analysis.Methods The CT images of the ankle and calcaneus of a normal adult were obtained.The Sanders typeⅢAB calcaneal fracture model and two types of fixation models of the calcaneus were constructed by software.After material assignment and mechanical loading,the displacement of the fracture block of each model was recorded and its stress distribution was analyzed.Results The peak displacement of the plate and screw in the locking plate fixation model was 0.13 mm,while the calcaneus displacement peak was 0.26 mm.The peak stress for the steel plate and screw was 281.10 MPa,and for the calcaneal bone block,it was 297.40 MPa.In the external fixation model,the external support exhibited a peak displacement of 0.17 mm,while the calcaneus demonstrated a peak displacement of 0.27 mm.The peak stress of calcaneal bone block was 38.13 MPa.Conclusion This external fixator is reliable and effective in the treatment of Sanders typeⅢAB calcaneal fracture.It provides sufficient biomechanical stability and introduces a novel approach for the treatment of calcaneal fractures.