可注射硫酸钙MIIGX3与医用骨水泥对椎弓根钉固定作用的比较研究

Comparison of the biomechanical effect of minimally invasive injectable graft 3 on pedicle screw fixation with that of bone cement

[目的]用可注射硫酸钙M IIGX3(m in im ally invasive in jectab le graft X3,以下简称M IIGX3)及医用骨水泥分别强化猪腰椎椎弓根钉内固定,测定椎弓根钉最大轴向拔出力,比较两种材料对椎弓根钉固定强度的影响。[方法]8个新鲜猪腰椎作为实验对象,在同一椎体双侧椎弓根制作钉道,一侧在固定螺钉前加用M IIGX3(M IIGX3组),另一侧加用骨水泥(骨水泥组)。24 h后行轴向拔出力测试。[结果]最大轴向拔出力,M IIGX3组1915±375 N,骨水泥组3625±775 N,二者配对t检验有显著差异(P<0.01)。[结论]骨水泥对椎弓根钉的固定作用大于M IIGX3。当存在脊柱滑脱需较大提拉力量或椎弓根钉需承受较大拔出力的节段,使用骨水泥进行强化更为合适。

[ Objective ] To compare the biomechanical effect of minimally invasive injectable graf X3 （MIIGX3 ） on strengthening pedicle screw fixation with that of bone cement. [ Method] Eight fresh pig lumbar vertebrae were harvested. One track was made in each vertebral pedicle. Before pedicle screw fixation, one track of one side bortebra was augmented with MIIGX3, and another side vertebra with bone cement. Pullout test was performed 24 hours after the fixation, and maximum axial pullout strength was measured. [Result]The maximum axial pullout strength is 1915 N±375 N in MIIGX3 group, and 3625 N ±775 N in bone cement group. There was significant difference between two groups（P 〈0.01 ）. [ Conclusion] Bone cement has much greater biornechanical effect on strengthening pedicle screw fixation than MIIGX3 does.