Micro-CT评价新型低弹β钛合金对动物骨质疏松性骨折愈合的影响  

The application of micro-computed tomography (microCT) for the assessment of the effect of the new low elastic modulus β Ti alloy on bone healing of osteoporotic fracture in an animal model

作　　者：沙漠[1] 郭征[1] 付军[1] 李述军[2] 李靖[1] 张涌泉[1] 吴智刚[1] 袁超凡[1] 石磊[1] 王军[1] 

机构地区：[1]第四军医大学西京医院全军骨科研究所,西安710032 [2]中科院金属研究所

出　　处：《中国骨质疏松杂志》2007年第10期704-708,共5页Chinese Journal of Osteoporosis

基　　金：国家自然科学基金资助项目(30471754)

摘　　要：目的micro-CT评价新型低弹β钛合金内植物对大鼠骨质疏松骨折愈合的作用及应力遮挡效应。方法SD雌性大鼠去势,建立骨质疏松动物模型,采用Utvag方法制备双股骨骨折模型,选用弹性模量分别为110GPa和30GPa的钛合金制成髓内针固定骨折,左侧为高弹组,右侧为低弹组,分别于术后2、4、6、12w行micro-CT测定,检测骨小梁的体积(BV)、样本体积(TV)、骨体积分数(BVF)、骨小梁间隙(Tb.Sp)、骨小梁厚度(Tb.Th)、骨小梁数(Tb.N)和结构模型指数(SMI)等指标,比较两种弹性模量钛合金植入物对骨折骨痂形成的影响,并进行统计学分析。结果骨质疏松大鼠股骨骨折后4w,兴趣区域1(ROI1)区,低弹组除TV、Tb.Sp高于高弹组外,BV、BVF、Tb.Th均低于高弹组;术后6w,ROI1区,低弹组TV值高于高弹组,其余差异无显著性;术后12w,ROI1区,低弹组TV、BV、Tb.N、Tb.Th、SMI均高于高弹组。ROI2区,低弹组BV、BVF、SMI均高于高弹组。结论新型低弹β钛合金内植物有利于大鼠骨质疏松骨折早期骨痂的形成,并提高骨折愈合的远期质量,减少了骨折固定节段的骨量丢失。Objective To investigate the influence of the low-modulus of elasticity （30 GPa） fixation on bone healing of osteoporotie fracture and the effects of stress shielding by miero-CT. Methods Thirty female Sprague- Dawley rats, aged 3 months, were selected, OVX was performed twelve weeks before femur fracture, the fracture of left femur was stabilized with the high-modulus of elasticity titanium alloy pin and the right with the low-modulus of elasticity. The bony calluses were observed miero-CT at two, four, six, and twelve weeks after fracture. The parameters included BV, TV, BVF, Tb. Th, Tb. N, Tb. Sp, SMI. Results The calluses at the low-modulus of elasticity group showed a significantly lower percentage of mineralized bone at 2 - 4 weeks postoperatively, and a higher amount of fibrous callus than the high-modulus of elasticity group. The calluses were no longer distinguishable at 6 - 9 weeks. The superior trabecular bone mierostructure was produced and less bone loss were shown under the low-modulus of elasticity pin at 12 weeks. Conclusion The new low elastic modulus β Ti alloy seemed to increase the fibrous callus formation at the initial phase, and improve the quality of bone healing at the later phase.

关 键 词：弹性模量 钛合金 micro—CT 骨质疏松性骨折 

分 类 号：R817.5[医药卫生—影像医学与核医学]