单侧PKP骨水泥注射过中线分布对压缩性骨折椎体两侧刚度的影响

目的:评价单侧椎体后凸成形术(PKP)中骨水泥注射超越椎体中线与否对椎体轴向及两侧刚度的影响。方法:3具防腐成人胸腰椎椎体标本(T4～L1)用于实验。通过MTS平台给椎体施加轴向压力,制作压缩性椎体骨折模型,同时进行球囊辅助下经单侧椎弓根穿刺椎体后凸成形术,根据骨水泥是否过椎体中线分为两组,骨水泥注射不过椎体中线(A组,n=9);骨水泥注射过椎体中线(B组,n=8),骨水泥注射量为椎体体积的10%。24h后放置在MTS-858材料实验平台上,给标本分别施加0～300N轴向和侧方压力载荷,记录并比较骨水泥注射术后,两组椎体轴向及两侧的刚度差异。结果:轴向压缩载荷下,A组与B组间轴向压缩刚度无显著差异(P>0.05);在椎体侧方压缩载荷下,尽管A组椎体骨水泥穿刺侧的刚度与B组间差异无显著性(P>0.05);但在非穿刺侧刚度上,B组显著高于A组,差异有显著性(P<0.05)。结论:行单侧PKP时,若骨水泥填充不过椎体中线时,则非穿刺侧刚度明显低于穿刺侧,而骨水泥填充过中线时,则两侧椎体刚度可同时得到显著强化。

Effects of cross-midline cement distribution on the stiffness of varied sites in compressive fractured vertebrae after unipedicular PKP:a biomechanical study

Objective:To evaluate the effects of cross-midline cement injection on axial and bilateral vertebral stiffness of varied sites in compressive fractured vertebrae after unipedicular PKP.Method:Vertebral bodies harvested from 3 cadaver spines(T4-L1) were experimentally induced into compressive vertebral fractures models by MTS.Subsequently the specimens were stabilized using transpedicular balloon-assisted PKP(group A,n=9,unipedicular hemivertebral,non cross-midline cement injection,group B,n=8,unipedicular c...