载阿仑膦酸钠骨水泥抑制钛磨屑诱导的假体周围骨溶解

目的 比较载阿仑膦酸钠丙烯酸骨水泥与皮下注射阿仑膦酸钠抑制钛磨眉诱导的骨溶解的效果.方法 48只成年雄性新西兰兔随机均分为无钛磨屑且无阿仑膦酸钠组(A组),有钛磨屑注射且无阿仑膦酸钠组(B组),钛磨屑分别注射0.1%、0.5%、1.0%载阿仑膦酸钠丙烯酸骨水泥组(C、I)、E组),钛磨屑注射且皮下手射阿仑膦酸钠组(F组),每组8只.将载阿仑膦酸钠骨水泥植入兔股骨远端.制备磨屑诱导骨溶解动物模型.术后8周对股骨行组织形态学分析、骨密度(bone mineral density,BMD)测定及界面力学测试结果 B组假体周围可见明显的骨溶解,而C、D、E、F组骨溶解明显少于B组.B组假体周围BMD和骨-骨水泥界面抗剪强度分别较A组下降17%和56%;D组假体周围BMD和界面抗剪强度较B组分别增加29%和62%;E组假体周围BMD和界画抗剪强度较B组分别增加37%和29%;F组假体周围BMD和界面抗剪强度较B组分别增加51%和69%;C组、D组、E组分别与F组比较,假体周围BMD和界面抗剪强度的差异均无统计学意义.结论 载阿仑瞵酸钠丙烯酸骨水泥与皮下注射阿仑瞵酸钠均可在一定程度上抑制磨屑诱导的骨吸收,增强界画抗剪强度.

Effects of local and systemic alendronate delivery on wear debris-induced osteolysis in vivo

Objective To investigate the effects of locally and systemically administered alendronate on wear-debris induced osteolysis in vivo. Methods Endotnxin-free titanium particles were injected into rabbit femurs prior to insertion of a non-weight-bearing polymethylmethacrylate plug into the distal femur canal. Then the particles were repeatedly injected into the knee 2, 4 and 6 weeks after the implantation. Alendronate was incorporated into bone cement for local delivery at three different concentrations 0.1, 0.5, and 1.0 weight%(wt%)]. For systemic delivery, alendronate was subcutaneously injected ( 1.0 mg· kg-1·week-1).Results Eight weeks after operation, there was significant evidence of osteolysis surrounding the plug in the control group, while markedly-blocked osteolysis was noted in the local delivery group (0.5 wt% and 1.0 wt%), and the systemic delivery group. It was found that alendronate had improved peri-prosthetic bone mineral density in a dose-effect model. Notably, no significant difference was found between local delivery of 0.5 wt% alendronate and systemic delivery in bone mineral density and implant fixation. Conclusion Alendronate-loaded bone cement (0.5 wt% ) may be as effective as the systemic delivery in inhibiting titanium particle-induced osteolysis.