Micro-CT评价唑来膦酸对磨损颗粒诱导假体周围骨溶解模型的抑制作用

Micro-CT evaluating inhibitory effect of zoledronic acid on polyethylene particle-induced periprosthetic osteolysis model

目的 :研究唑来膦酸对磨损颗粒诱导假体周围骨溶解大鼠模型的骨微结构的影响。方法 :选取30只成年雄性SPF级SD大鼠(重250~300 g),随机分成假手术组、模型组和唑来膦酸组,每组10只。通过往大鼠右侧股骨置入钛钉和聚乙烯颗粒进行造模,术后3 d假手术组、模型组皮下注射0.9%生理盐水2 ml/kg,唑来膦酸组皮下注射唑来磷酸0.1 mg/kg,每周1次,共8周。8周后取各组大鼠右侧股骨标本采用Micro-CT对大鼠股骨松质骨微结构进行扫描,应用三维重建处理和分析软件进行处理得到图像及BMD、BV/TV、Tb.N、Tb.Th、SMI、BS/BV、Tb.Sp、Tb.Pf等参数进行分析。结果:Micro-CT三维成像显示,模型组大鼠股骨骨密度较假手术组明显下降,骨微结构破坏严重,骨小梁稀疏变细,连续性降低;唑来膦酸组与模型组比较,骨微结构又出现明显改善。对大鼠股骨微结构的Micro-CT参数进行分析,模型组大鼠股骨BMD(0.081±0.020)明显低于假手术组(0.160±0.018)及唑来膦酸组(0.125±0.012),差异有统计学意义;模型组大鼠股骨BV/TV(10.563±1.070)低于假手术组(27.935±1.834)及唑来膦酸组(14.559±1.258),差异有统计学意义;模型组大鼠股骨Tb.N(1.005±0.165)低于假手术组(2.058±0.108)及唑来膦酸组(1.515±0.126),差异均有统计学意义;模型组大鼠股骨Tb.Th(0.075±0.016)明显低于假手术组(0.158±0.016)及唑来膦酸组(0.124±0.011),差异均有统计学意义。同时,模型组大鼠股骨SMI(1.817±0.127)明显高于假手术组(1.104±0.120)及唑来膦酸组(1.547±0.122),差异均有统计学意义;模型组大鼠股骨BS/BV(35.784±1.650)明显高于假手术组(21.506±2.771)及唑来膦酸组(30.399±2.730);模型组大鼠股骨Tb.Sp(0.735±0.107)高于假手术组(0.423±0.057)及唑来膦酸组(0.577±0.082),差异均有统计学意义;模型组大鼠股骨Tb.Pf(9.088±1.283)明显高于假手术组(2.447±0.703)及唑来膦酸组(5.862±1.042),差异有统计学意义。结论:唑来膦酸可以通过改变大鼠骨微结构达到抑制磨损颗粒诱发的骨溶解的作用,为使用唑类酸作为一种治疗性干预手段来防止假骨溶解提供了科学依据。

Objective：To observe inhibitory effect of zoledronic acid on polyethylene particle-induced periprosthetic osteolysis model. Methods：Thirty male adult specific-pathogen-free SD rats（weighted 250 to 300 g） were randomly divided into sham group,model group,and zoledronic acid group,10 in each group. Modeling were building by titanium screws and polyethylene particles implanted into right femur of rats,sham group and model group were performed hypodermic injection by0.9% saline with 2 ml/kg,zoledronic acid with 0.1 ml/mg were injected into zoledronic acid group,once a week for 8 weeks.After 8 weeks,right femur specimens were drawn and used to san microstructure of femoral cancellous bone in rats model was examined by Micro-CT,and the images were treated with three-dimension reconstruction and analysis software BMD,BV/TV,Tb.N,Tb.Th,SMI,BS/BV,Tb.Sp and Tb.Pf and other parameters include. Results：According to Micro-CT three-dimensional imaging,BMD in model group was significantly decreased than sham group,bone microstructure damage was serious,bone trabecula changed thinning continuity; while bone microstructure was obviously improved compared with model group and zoledronic acid group. After analyzing Micro-CT parameters of femur microstructure,BMD in model group（0.081±0.020） was significantly decreased than control group（0.160±0.018） and zoledronic acid group（0.125 ±0.012）; BV/TV in model group（10.563±1.070） was obviously lower than control group（27.935±1.834） and zoledronic acid group（14.559±1.258）; Tb.N in model group（1.005±0.165） was lower than control group（2.058±0.108） and zoledronic acid group（1.515±0.126）; while Tb.Th in model group（0.075±0.016） was decreased than control group（0.158±0.016） and zoledronic acid group（0.124±0.011）.Meanwhile,SMI in model group（1.817±0.127） was significantly higher than control group（1.104±0.120） and zoledronic acid group（1.547±0.122）; BS/BV in model group（35.784±1.650） was higher than control group（21.506±2.771） and zoledronic acid group（30.399±2.730）; Tb.Sp in model group（0.735±0.107） was higher than control group（0.423±0.057） and zoledronic acid group（0.577±0.082）,TB.Pf in model group（9.088±1.283） was higher than control group（2.447±0.703） and zoledronic acid group（5.862±1.042）. Conclusion：Zoledronic acid could change bone microstructure of rats to inhibit polyethylene particle-induced bone solution,which provides a scientific basis for prevent bone solution by zoledronic acid as a therapeutic intervention.