异体骨接骨板联合不同螺钉治疗股骨干骨折有限元分析

目的对比分析异体骨接骨板分别联合可吸收螺钉(聚-DL-乳酸)和钛合金螺钉(Ti-6Al-4V)治疗股骨干骨折的应力分布情况,验证可吸收螺钉的强度,为临床提供力学依据。方法利用螺旋CT扫描股骨,将扫描数据以DICOM格式导入mimics软件中,建立股骨三维模型。在proe5.0中建立接骨板模型和螺钉模型(简化为圆柱),装配完成后,导入ansys12.0划分网格、材料赋值,并施加700 N轴向载荷、15 N·m弯曲载荷、15 N·m扭转载荷。结果在三种载荷下6根可吸收螺钉最大主应力的最大值为5.75 Mpa、6根钛合金螺钉最大主应力的最大值为24.9 Mpa;两种不同螺钉固定下,股骨和接骨板的应力分布基本相同。结论可吸收螺钉适应于同种异体骨接骨板的固定,与钛合金螺钉相比,具有减少骨头螺钉孔处的应力遮挡的优点。

Finite Element Analysis of Allogeneic Bone Plates Combined with Different Screw in the Treatrment of Femoral Shaft Fractures

Objective To comparative analysis of two different screws allogeneic bone plate in the treatment of femoral fracture stress distribution,and to provide the mechanical basis for the clinical.Methods CT images of femur were obtained from spiral ct,which were subsequently imported into mimics software according to DICOM standard,and then built a three-dimensional model of the femur.Built bone plates model and screws model（ simplified cylinder） in proe 5.0 and then importing into ansys12.0 meshed and assigned with material properties after assembly was completed.And applying 700 N axial load,15N·M bending load,15 N·M torsional load.The maximum value of 6 absorbable screw＇s maximum principal stress is 5.75 Mpa,of 6 titanium screws is 24.9 Mpa under the three load.Two different screws,the stress distribution of the femur and the bone plate is substantially the same.Conclusion Absorbable screw adapted to allogeneic bone plates fixation,compared with titanium screws,has the advantage of reducing the bone screw holes at the stress shielding.