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2022, Vol. 26 ›› Issue (6): 858-863Positive effect of supracondylar femoral osteotomy on the correction of knee varus based on three-dimensional reconstruction and finite element analysisLi Shuo1, Su Peng1, Zhang Li2, Wu Qiulong1, Hu Xiangyu1, Lai Yuliang1
Abstract: BACKGROUND: Studying the effect of supracondylar femoral osteotomy in treatment of varus knee from the direction of biomechanics can have a positive effect on the understanding of the surgical treatment of knee varus deformity by osteotomy. OBJECTIVE: Based on the CT data, the preoperative and postoperative three-dimensional models of the knee joint of supracondylar femoral osteotomy are constructed. A modeling method of tissue is introduced. The feasibility of the method and the positive effect of supracondylar osteotomy of femur was verified through biomechanical analysis. METHODS: The preoperative and postoperative CT data of a patient with supracondylar femoral osteotomy surgery were selected at random to establish the knee bone model based on image segmentation, and the three-dimensional model of the knee meniscus and major ligaments between knee joints was established based on contour extension. After meshing and material definition, the load was applied under the same working condition (1 000 N, in the direction of lower limb force line), and the finite element simulation was carried out on the preoperative and postoperative model. Compared with the research results, the feasibility of modeling method was tested. The stress difference at the proximal tibia and the changes of stress peak point with time of preoperative and postoperative knee joint were studied. RESULTS AND CONCLUSION: (1) The postoperative peak of medial tibia was 2.334 MPa and the lateral tibia peak value was 2.819 MPa. The differences of stress from the previous scholars were contrasted to test the effectiveness of the model and the feasibility of the modeling method. (2) The preoperative peak tibial stress was 7.085 MPa, which was higher than the postoperative peak tibial stress (2.819 MPa). Meanwhile, with the change of time, the stress concentration of tibia before operation was more obvious, and the stress concentration of tibia after operation had been improved. (3) Results indicated that supracondylar femoral osteotomy had a positive effect on the correction of varus knee. Key words:image segmentation, supracondylar osteotomy of femur, grid division, finite element simulation, contact stress, effectiveness |