青少年特发性脊柱侧凸Lenke5型胸腰段后路矫形后钛棒有限元分析

Finite element analysis of titanium rods after adolescent idiopathic scoliosis Lenke5 type thoracolumbar correction

目的通过对矫形后Lenke5型青少年特发性脊柱侧凸(AIS)患者T3~L5节段钛棒应力变化分析,为Lenke5型AIS手术改进提供参考。方法建立1例2018年8月25日于内蒙古医科大学第二附属医院行侧凸矫形手术患者脊柱T3~L5节段三维有限元模型,随机采集前屈,后伸,左、右侧屈,左、右旋转六种工况下椎体与钛棒连接处5个应力点,利用SPSS 22.0进行统计分析,分析钛棒应力变化趋势。结果在前屈,后伸,左、右侧屈工况下,钛棒应力呈“W”型变化;在左、右旋转工况下,钛棒应力呈“〈”型变化;钛棒在T11(胸弯下端椎)与T12(腰弯上端椎)应力较大。结论钛棒在胸弯下端椎与腰弯上端椎应力较大,尤其在左、右旋转工况下。

Objective To analyze the changes of the titanium rod stress in the T3-L5 segment of Lenke5 type adolescent idiopathic scoliosis(AIS)patients after correction,and provide reference for the improvement of Lenke5 type AIS surgery.Methods A three-dimensional finite element model of the T3-L5 spine segment of a patient who underwent scoliosis correction surgery in the Second Affiliated Hospital of Inner Mongolia Medical University on August 25,2018 was established.The five stress points at the junction of the vertebral body and the titanium rod under six working conditions of anterior flexion,posterior extension,left and right flexion,left and right rotation were randomly collected.SPSS 22.0 was used for statistical analysis to analyze the stress change trend of the titanium rod.Results Under the working condition of anterior flexion,posterior extension,left and right flexion,the stress of the titanium rod showed a“W”-shaped change,and a“〈”-shaped change under left and right rotation conditions.Titanium rods had greater stress on T11(lower thoracic curve)and T12(upper lumbar curve).Conclusion Titanium rods have greater stress in the lower end vertebrae of thoracic curve and upper end vertebra of lumbar curve,especially under left and right rotation conditions.