阿仑膦酸钠局部释放对假体周围骨溶解的抑制作用

目的 通过阿仑膦酸钠(ALN)复合羟基磷灰石(HA)涂层假体,检测局部释放的ALN对骨溶解的抑制作用. 方法 选择18只雌性新西兰大白兔,随机均分为实验组、阳性对照组和空白对照组,三组均于左侧胫骨平台处向胫骨髓腔竖直植入HA涂层假体.在植入前,实验组于HA涂层表面复合ALN 5 mg,且实验组和阳性对照组涂层表面均匀涂抹25μg超高相对分子质量聚乙烯颗粒,空白对照组不做处理.术后12周取左侧胫骨行骨组织形态学、生物力学以及影像学测馈,检测ALN体外释放周期,并评估抗骨溶解效果. 结果 与对照组相比,实验组的骨皮质厚度(+9.26%)、假体生物力学固定强度(极限抗剪强度:+36.42%、表观抗剪刚度:+37.79%、总能量吸收值:+30.00%)、骨-假体接触率(+44.40%)、假体周围骨体积分数(+16.07%)、骨矿化水平(钙盐沉积岛平均而积:+598.86%、钙盐沉积岛面积分数:+650.11%)和假体周围骨密度(+62.05%)均明显增高,差异有统计学意义(P<0.05);反映成骨细胞活性的各项参数(类骨质表面:+33.53%、类骨质厚度:+49.60%、骨形成速率:+91.62%、松质骨骨矿沉积率:+48.04%、皮质骨骨矿沉积率:+60.42%)也有不同程度的增高,差异有统计学意义(P<0.05). 结论 非多孔HA涂层假体复合ALN的局部释放可以明显抑制超高相对分子质量聚乙烯颗粒诱导的假体周围骨溶解,ALN在预防磨屑诱导的假体周围骨溶解过程中能够增强成骨细胞活性.

Locally released alendronate in HA-coating prosthesis inhibits osteolysis induced by wear debris of ultro-high molecular weight polyethylene

Objective To test the effect of locally released alendronate in the HA-coating of pros-thesis on the osteolysis induced by wear debris of ultro-high molecular weight polyethylene (UHMWPE). Methods Eighteen female New Zealand rabbits were divided into 3 groups randomly (experimental group, positive control group and blank control group). HA-coating implants were inserted into the left tibial cavities. Prior to implantation, 5 mg of ALN was added into the HA-coating in the experimental group, while 25 μg of UHMWPE particles were laid evenly on the coating in the experimental and positive control groups but nothing in the blank control group. After 12 weeks, histomorphometry, biomechanical test and SEM were performed to evaluate the anti-osteolysis effects of the prostheses. The alendronate release cycle was examined in vitro. Results Compared with control groups, cortical bone thickness (+ 9.26%), biomechanical implant fixa-tion (ultimate shear strength: + 36.42%, apparent shear stiffness: + 37.79%, total energy absorption: + 30.00%), bone-to-implant contact (+44.40%), peri-implant bone volume fraction (+16.07%), bone mineralization (average area of calcium deposit islands: +598.86%, percentage of calcium deposit islands: +650.11%), and peri-implant bone density (+62.05%) all increased in the experimental group, and the parameters indicating the osteoblast activity also increased (osteoid surface: +33.53%, osteoid thickness: +49.60%, bone formation rate: +91.62%, mineral apposition rate: +48.04%, endosteal mineral ap-position rate: +60.42% ) . Conclusion Locally released ALN from a non-porous HA-coating implant can significantly suppress the peri-implant osteolysis induced by UHMWPE particles, and can boost the os-teoblast activity at the same time as well.