有限元法分析髋关节表面置换后髋关节的力学特点

摘要

背景:有限元分析在全髋关节置换中的研究比较多,对髋关节表面置换后生物力学分布特点的研究较少.目的:三维有限元法分析髋关节表面置换后髋关节的生物力学特点.方法:建立金属对金属髋关节表面置换后的三维有限元模型,在髋臼侧加载与重力线平行的350 N载荷,观察假体应力分布、股骨应力分布和股骨头不同区域应力值.结果与结论:①髋臼杯沿和髋臼主体的应力值分别为(0.63±0.34)MPa和(1.89±0.67)MPa,髋臼杯沿的应力值高于髋臼主体(P<0.05);②应力集中在股骨颈,股骨头和股骨颈交界处出现应力遮挡,股骨假体柄周围骨质的应力值为(158.24±28.79)MPa,股骨假体柄应力值为(186.46±22.37)MPa,股骨假体柄周围骨质和股骨假体柄的应力值比较差异无显著性意义(P>0.05);③股骨头分区8个区域之间应力值差异有显著性意义(P<0.05),区域6和区域8的应力值高于其他区域(P<0.05);④表明金属对金属髋关节表面置换后股骨颈应力集中,股骨假体侧应力遮挡,股骨颈内侧、股骨颈假体和骨质交界处的应力较大.%BACKGROUND:There are many researches on the finite element analysis of total hip arthroplasty, but the biomechanical distribution after hip surface replacement is little reported.OBJECTIVE: To analyze the biomechanical characteristics after hip surface replacement based on three- dimensional finite element analysis.METHODS: The three-dimensional finite element model after metal-to-metal hip surface replacement was established.The load of 350 N paralleling to the gravity line was loaded on the acetabulum. The stress distribution of the prosthesis and femur and the stress of the different regions of the femoral head were observed.RESULTS AND CONCLUSION: (1) The stress value of the acetabular cup was significantly higher than that of the acetabular body ((0.63± 0.34) vs. (1.89±0.67) MPa, P < 0.05). (2) The stress was concentrated on the femoral neck. The femoral head and femoral neck junction appeared with stress occlusion. The stress around the femoral prosthesis stem was (158.24±28.79) MPa, and the stress value of the femoral prosthesis stem was (186.46±22.37) MPa, showing no significant difference (P > 0.05). (3) The stress value showed significant difference among femoral head regions (P <0.05), and the stress of the regions 6 and 8 was significantly higher than that of the other regions (P < 0.05). (4) These results show that after metal-to-metal hip surface replacement, femoral neck stress is concentrated, the stress of the femoral prosthesis is occluded, and the stress at the medial femoral neck as well as the junction of femoral neck prosthesis and bone is larger.