Micro-CT动态观察骨质疏松骨折的愈合  

Dynamic observation of osteoporotic fracture healing using micro-CT

作　　者：王耀琴[1,2] 彭江[1] 眭翔[1] 赵钧如[1] 薛静[1] 许文静[1] 汪爱媛[1] 卢世璧[1] 覃秀桃[2] 

机构地区：[1]中国人民解放军总医院骨科研究所,北京100853 [2]山西医科大学,太原030001

出　　处：《中国骨质疏松杂志》2013年第3期283-287,共5页Chinese Journal of Osteoporosis

基　　金：国家自然基金(30872633);国家科技支撑计划(2009BA187B02);军队"十二五"重点项目(BWS11J025);国家重点基础研究发展计划(2012CB518106)

摘　　要：目的通过Micro-CT探讨骨质疏松大鼠股骨干骨折愈合过程中骨痂的体积、骨矿物密度、骨小梁结构等的动态变化规律。方法将清洁级4月龄雌性Wistar大鼠40只,体重300 g±20 g,行双侧卵巢切除术(OVX),3个月后形成骨质疏松模型。进行股骨干中段骨折造模,髓内钉固定。骨折固定术后,分别于术后4周,6周,8周,12周进行骨折端显微CT观察,并进行骨结构和骨矿物密度(BMD)的定量分析。术后12周取材进行组织学观察。结果骨质疏松大鼠骨折后8周骨折区骨痂总体积(Total Volume,TV)、骨痂中高矿化组织出现下降趋势,但无统计学差异。骨组织占骨痂总体积的比率(Bone Volume Fraction,BVF)随时间点有明显上升趋势,且12周后显著大于4周。骨痂中总体矿物密度(Bone Mineral Density,BMD),12周明显高于4周。矿化组织自身的密度(TissueMineral Density,TMD),12周高于4周,8周于6周比较,均有显著性差异。骨小梁厚度(Tb.Th)和骨小梁间隙(Tb.SP),12周与4周、6周比较均有显著性差异,且Tb.SP在12周出现下降,12周时改建塑型基本完成。组织学观察显示,术后12周,骨折断端板层骨改建形成骨小梁,恢复骨结构的完整性。结论对于骨质疏松骨折大鼠早期,Micro-CT分析显示骨痂数量因损伤而增加,但软骨性骨痂至骨痂演变过程较慢。骨折后期,矿化诱导新骨生成,且骨折大鼠在12周基本完成矿化,从而促进骨折修复。Objective To investigate the dynamic change of callus volume, bone mineral density （BMD） , and trabecullar bone structure during the healing of osteoporotic femoral shaft fractures in rat using micro-CT. Methods A total of 40 4-month-old female Wistar rats, weighted 300 ± 20 g, received bilateral ovariectomy （OVX）. The osteoporosis model was established after 3 months. The middle of the femoral shaft was fractured and intramedullarily nailed. Bone structure and BMD were observed on 4 - , 6 - , 8 - , and 12- week using micro-CT after the operation. Histological observation was performed at the 12^th week after the operation. Results The callus total volume （TV） andhigh-mineralized tissue in the callus declined at the 8^th week, but there was no significant difference. Bone volume fraction （BVF） was in a upward trend, and BVF at the 12^th week was significantly larger than that at the 4^th week. BMD at the 12^th week was significantly higher than that at the 4^th week. The tissue mineral density （TMD） at the 12^th week was higher than that at the 4^th week. TMD of the 8^th week was higher than that at the 6^th week. Trabecular thickness （Tb. Th） and trabecular bone sepatium （Tb. SP） at the 12^th week were significantly different compared to those at the 4^th week and the 6^th week. Tb. SP declined at the 12^th week. The process of remodeling was basically completed at the 12^th week. Histological observation showed that the lamellar bone of fracture fragments remodeled into trabecular bone and restored the integrity of the structure. Conclusion The micro-CT analysis reveals that the number of callus increases due to injury at early stage of osteoporotic fractures in rats. The changing of cartilage bone callus into bone callus is a slow evolutionary process. New bone formation is induced by mineralization at the later stage of fracture. The mineralization is basically completed at the 12^th week, which contributes to the repair of the fracture.

关 键 词：骨质疏松骨折 Micro—CT 

分 类 号：R580[医药卫生—内分泌] R683[医药卫生—内科学]