Three-dimensional finite element analysis of pediclesubtraction osteotomy for ankylosing spondylitis with kyphotic deformity / 中国组织工程研究

ABSTRACT

BACKGROUND: The effect of pediclesubtraction osteotomy is obvious, and the incidence of correction degree loss is low. So, it has been the first choice for the correction of ankylosing spondylitis with kyphotic deformity. OBJECTIVE: To establish a three-dimensional finite element model of ankylosing spondylitis with kyphotic deformity by computer aided software, and to analyze the biomechanical characteristics.METHODS: A ankylosing spondylitis patient with kyphotic deformity was selected, and spinal full-length anteroposterior images were photographed, and the patient received magnetic resonance imaging. A three-dimensional model of ankylosing spondylitis with kyphotic deformity was established, and then a three-dimensional finite element model of ankylosing spondylitis with kyphotic deformity was generated. Three different types of models were established for three different surgeries at the osteotomy angle of 20°, 30° and 40°. Correction effect and biomechanics were analyzed. RESULTS AND CONCLUSION: (1) A three-dimensional finite element model of ankylosing spondylitis with kyphotic deformity was successfully established at the osteotomy angle of 20°, 30° and 40°. The maximum principal stresses of three different screw titanium rods were 54.632, 194.230, 394.860 Mpa. (2) Three different surgeries were successfully simulated. The correction degree of the model 3 was optimal, but the stress distribution was large; displacement was obvious. After internal fixation, the complications of stability and internal fixation failure increased. The model 2 had good correction degree, appropriate stress distribution, and decreased complications of fixation failure.