ABSTRACT
BACKGROUND: Patients with severe ankylosing kyphosis are often treated with orthopedic osteotomy, but with high surgical risk, treatment schemes are individualized, and the biological morphology and mechanical properties of the deformed spine are complex. Meanwhile, the finite element model is more adaptable for biomechanical analysis of the spinal deformity. However, its application in the treatment of ankylosing kyphosis in China was little reported.OBJECTIVE: To establish an ankylosing kyphosis finite element model so as to investigate the relationship between different osteotomy methods and the deformation and stress distribution of the spine.METHODS: A three-dimensional finite element model of ankylosing kyphosis was established, and then imported into ANASYS software, to simulate vertebral column decancellation and vertebral column resection at T12 and L1 levels,respectively. The vertebrae and screw were loaded with the same load, and deformation and stress nephograms were obtained.RESULTS AND CONCLUSION: (1) The deformation of the osteotomy at T12 level was significantly larger than that at L1 level. (2) The stress distribution of the decancellation osteotomy concentrated on the pedicle screw and titanium bar; the stress concentration of vertebral column resection was the intervertebral cage. (3) Individualized surgical treatment of ankylosing kyphosis may influence the selection of the osteotomy segment and osteotomy operation. The osteotomy segment may affect the stability of the spine, and stress distribution of internal fixation is likely related to the method of internal fixation. (4) This conclusion may provide theoretical reference for the biomechanical study of analysing ankylosing kyphosis.