Finite element analysis of the mechanical properties of the hip joint after hip surface replacement

Shi Liang; Hui Wen-bin; Liu Zong-zhi; Yang Pei

doi:10.3969/j.issn.2095-4344.2017.27.001

Abstract：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.