Finite element analysis of kyphosis in ankylosing spondylitis treated by different osteotomy methods / 中国组织工程研究

ABSTRACT

BACKGROUND: Kyphosis in ankylosing spondylitis is sagittal or coronal imbalance, but there is a lack of study on its orthopedic biomechanics, and biomechanics is of great significance for the reconstruction of spinal stability after orthopedic surgery.OBJECTIVE: To establish a three-dimensional (3D) finite element model of kyphosis in ankylosing spondylitis treated by osteotomy on software, and to analyze its biomechanical properties, thus providing theoretical basis for clinical practice.METHODS: A 3D finite element model of kyphosis in ankylosing spondylitis was established based on CT data, and the predetermined angle of the osteotomy at L2 was measured. Afterwards, vertebral column decancellation and vertebral column resection were stimulated, and then the biomechanical parameters were analyzed. RESULTS AND CONCLUSION: (1) The 3D finite element models of kyphosis in ankylosing spondylitis treated by vertebral column decancellation or vertebral column resection at L3 were established successfully. (2) The stress on the screw and contact at each segment in the vertebral column decancellation group was significantly higher than that in the vertebral column resection group except for S1. (3) To conclude, both two methods can reconstruct the sagittal balance,but vertebral column decancellation exhibits significantly higher stress on the screw. Indeed, the incidence of internal fixation failure and complications in vertebral column decancellation is higher than that in vertebral column resection at the same segment and angle.