新型低弹高强度β钛合金对大鼠骨质疏松性骨折愈合的影响  

Effects of novel β titanium alloy with high strenghth and low elastic modulus on bone healing of osteoporotic fracture in rats

作　　者：沙漠[1] 郭征[2] 付军[2] 李述军[3] 李靖[2] 吴智刚[2] 袁超凡[2] 石磊[2] 王军[2] 

机构地区：[1]解放军第一七五医院骨科,漳州363000 [2]第四军医大学附属西京医院全军骨科研究所 [3]中国科学院金属研究所

出　　处：《中华创伤杂志》2009年第12期1123-1128,共6页Chinese Journal of Trauma

基　　金：国家自然科学基金资助项目（30471754）,国家高技术研究发展计划（863计划）资助项目（2007AA03ZA31）

摘　　要：目的评价新型低弹β钛合金内置物对大鼠骨质疏松骨折愈合的作用及应力遮挡效应。方法40只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33GPa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6，12周行组织学、Micro—CT及生物力学检测，Micro—CT检测指标为骨小梁的体积（BV）、样本体积（TV）及骨体积分数（BVF），生物力学检测指标为最大载荷，比较两种弹性模量钛合金置人物对骨折骨痂形成及力学特性的影响，并进行统计学分析。结果低弹组显示了更多的胶原及骨痂形成，骨小梁更厚，板层骨排列更加规则。骨质疏松大鼠股骨骨折后6周，低弹组ROI 1区TV值高于高弹组（P〈0．05），其余差异无统计学意义；术后12周，低弹组ROI 1区TV值、BV值均高于高弹组（P〈0．05）。低弹组R012区BV高于高弹组（P〈0．05）。生物力学检测提示低弹组最大载荷优于高弹组。结论新型低弹B钛合金内置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 effects of a novel β titanium fixation with high strength and low elastic modulus on bone healing of osteoporotic fracture and its effects on stress shielding. Methods Forty female Sprague-Dawley rats were oophorectomized before establishment of femur fracture model. The fracture of left femur was stabilized by titanium alloy pin with high elastic modulus （ 110 GPa, high elasticity modulus group） and the fracture of right femur by titanium alloy pin with low elastic modulus （30 GPa, low elasticity modulus group）. Six and 12 weeks later, the bone volume （BV）, total volume （TV） and bone volume fraction （BVF） were detected by Micro-CT, and the maximum load was detected by biomechanical test. The effects of two titanium alloy pins on formation of bony calluses and mechanical properties of bones were compared. Results Compared with the low elasticity modulus group, more collagen and bony callus, thicker bone trabeculae and more regular lamellar bone were found in the high elasticity modulus group. In low elasticity modulus group, TV （ROI 1） was increased obviously at week 6, with no statistical differences in BV （ ROI 1 ）, BV （ ROI 2 ） and maximum load between two groups （P 〈 0.05 ）. TV and BV in region ROI 1 in the low elasticity modulus group were significantly higher than that in high elasticity modulus group （ P 〈 0.05 ）, while BV in region ROI 2 in low elasticity modulus group was significantly higher than that in high elasticity modulus group at week 12 postoperatively （ P 〈 0.05 ）. Biomechnical test indicated that the maximum load in low elasticity modulus group was higher than that in high elasticity modulus group. Conclusions The novel β titanium alloy with high strength and low elastic modulus helps reduce effects of stress shielding, diminish bone resorption, increase the fibrous callus formation at the initial phase and improve the quality of bone healing at the later phase.

关 键 词：骨质疏松 股骨骨折 钛 大鼠 弹性模量 

分 类 号：R687.3[医药卫生—骨科学]