短节段椎弓根螺钉置入内固定椎体成形治疗胸腰椎骨折的生物力学检测  

Biomechanics of vertebroplasty-augmented short-segment pedicle screw fixation of traumatic thoracolumbar fractures

作　　者：李家谋[1] 张昆亚[2] 韩伟峰[1] 林欣[1] 刘志成[2] 

机构地区：[1]首都医科大学附属北京天坛医院骨科,北京市100050 [2]首都医科大学生物工程学院生物力学实验室,北京市100069

出　　处：《中国组织工程研究与临床康复》2011年第39期7284-7287,共4页Journal of Clinical Rehabilitative Tissue Engineering Research

摘　　要：背景:为避免单纯椎弓根螺钉置入内固定治疗胸腰段骨折出现的内固定物松动、断裂,及合并植骨时出现的骨折不愈合、后凸畸形丢失,而发展的短节段椎弓根螺钉合并椎体成形技术治疗胸腰段骨折,临床已有应用,但其生物力学方面鲜有研究。目的:观察应用椎弓根螺钉置入内固定椎体成形治疗胸腰椎骨折的生物力学变化。方法:12个冻存的新鲜胸腰段脊椎(T12～L2)标本,用于制备胸腰椎骨折模型,备测试。分为3组,经皮椎体成形术组:给予经单侧椎弓根注入低黏度的含对比剂骨水泥5～7mL;椎弓根螺钉内固定组:于T12、L2椎弓根置入螺钉;强化组:行椎弓根螺钉内固定的同时行伤椎骨水泥椎体成形术,测试各组静态最大抗压强度及刚度。结果与结论:骨水泥分布面积皆大于50%,经皮椎体成形术组和椎弓根螺钉内固定组最大静态抗压强度与刚度均小于强化组最大强度和刚度(P<0.05)。椎弓根螺钉内固定组椎弓根螺钉较小强度下出现弯曲,而强化组在达到极性轴向压缩强度时才出现弯曲。提示应用短节段椎弓根钉置入内固定椎体成形治疗胸腰椎骨折提高了固定的强度及刚度,并且维持了复位伤椎高度,提高了稳定性,减少了椎弓根螺钉的并发症。BACKGROUND：Vertebroplasty-augmented short-segment pedicle screw fixation is developed to avoid implant loosing,rupture,bone nonunion,and loss of kyphosis due to single pedicle screw fixation for treatment of thoracolumbar fractures.This treatment has been applied in clinic,but the relevant biomechanical studies are rare.OBJECTIVE：To observe the biomechanical changes in the treatment of traumatic thoracolumbar fractures with short-segment pedicle screw fixation with vertebroplasty.METHODS：Twelve fresh frozen thoracolumbar spines（T12-L2） were used.Models of traumatic thoracolumbar fractures were prepared and divided into three groups：Percutaneous vertebroplasty（PVP） group,pedicle screw fixation group,and PVP-augmented short-segment pedicle screw fixation group.RESULTS AND CONCLUSION：In the three groups,the cement distribution area was all beyond 50% vertebral body.The failure load and stiffness in the PVP-augmented short-segment pedicle screw fixation group were higher than those in the other two groups（P 0.05）.Screw bending formed due to a lower intensity in the pedicle screw fixation group than that in the PVP-augmented short-segment pedicle screw fixation group.Vertebroplasty supplementation may improve the axial pullout strength,failure load and stiffness of the short-segment pedicle screw.It is important for decreasing the incidence of pedicle screw failure and progressive spinal deformity.

关 键 词：胸腰椎骨折 椎体成形 生物力学 椎弓根螺钉 内固定 

分 类 号：R318[医药卫生—生物医学工程]