目的

建立新西兰兔牵张成骨模型，利用Micro-CT骨微结构指标探讨骨碎补总黄酮对牵张成骨模型脊柱骨量的影响。

方法

普通级新西兰兔12只，雄性，体重 1.8～2.2 kg，按随机数表法随机分为3组：空白组、对照组和实验组，每组4只动物。对照组与实验组进行牵张成骨造模，空白组行假手术；术后实验组给予骨碎补总黄酮（0.03 g·kg^-1·d^-1），另两组予等量生理盐水灌胃60 d。随后处死取同一节段脊柱骨行标本Micro-CT扫描，获取骨密度（BMD）、骨体积分数（BV/TV）、骨小梁分离度（Tb.Sp）骨小梁厚度（Tb.Th）、骨小梁间隙（Tb.N）、骨表面积骨体积比值（BS/BV），采用单因素方差分析比较三组间数据，多重比较采用LSD检验。

结果

术后观察所有家兔活动正常，对照组与实验组兔子奔跑、跳跃等动作减少。Micro-CT定量分析显示：三组比较，BMD、BS/BV、Tb.Th、Tb.N、BV/TV、Tb.Sp等值差异有统计学意义（F=3.751、3.141、8.590、4.037、4.133、5.110，均为P＜0.05）。组间两两比较显示，与空白组相比，对照组BMD、Tb.Th、Tb.N、BV/TV下降，BS/BV、Tb.Sp升高（均为P＜0.05）；与实验组相比，对照组的BMD、Tb.Th、Tb.N、BV/TV下降，Tb.Sp升高（均为P＜0.05）；空白组与实验组相比差异无统计学意义（均为P＞0.05）。

结论

牵张成骨术后存在脊柱椎骨骨量减少的现象，有骨质疏松的风险存在。骨碎补总黄酮可维持牵张成骨模型的脊柱骨量，预防骨质疏松的发生。

Objective

To establish a New Zealand rabbit distraction osteogenesis model， and to investigate the effect of total flavonoids of drynaria rhizome on spinal bone volume of distraction osteogenesis model by Micro-CT bone microstructure indices.

Methods

Twelve New Zealand male rabbits， weighing 1.8 to 2.2 kg， were randomly divided into three groups according to the random number table method： the blank group， the control group and the experimental group， with four animals in each group. The control and experimental groups were subjected to distraction osteogenesis modelling， and the blank group were subjected to sham operation. After the operation， the experimental group were given total flavonoids of drynaria rhizome（0.03g·kg^-1·d^-1 ） ， and the other two groups were given equal amounts of saline lavage for 60 d. After the animal was sacrificed， the same spinal bones were removed and scanned by micro-CT. Bone mineral density （BMD），bone volume fraction （BV/TV）， trabecular separation （Tb.Sp）， trabecular thickness （Tb.Th）， trabecular gap （Tb.N） and bone surface area to bone volume ratio （BS/BV） were measured. One-way ANOVA was used to analyse the data of the three groups， and LSD test was used for multiple comparisons.

Results

All the rabbits were observed and showed normal activities after operation. The rabbits in the control and experimental groups showed a decrease in running and jumping. Quantitative analysis of micro-CT showed statistically significant differences in BMD， BS/BV， Tb.Th， Tb.N， BV/TV， and Tb.Sp among the three groups （F=3.751， 3.141， 8.590， 4.037， 4.133，5.110， all P＜0.05）. BMD， Tb.Th， Tb.N， BV/TV decreased， and BS/BV and Tb.Sp increased in the control group compared with the blank group （all P＜0.05）. Compared with the experimental group， BMD， Tb.Th， Tb.N， BV/TV decreased and Tb.Sp increased in the control group （all P＜0.05）； the difference was not statistically significant in the blank group compared with the experimental group （all P ＞0.05）.

Conclusions

Bone mass may decrease after distraction osteogenesis， this may lead to a risk of osteoporosis. The total flavones of drynaria rhizome can maintain the spine bone mass of distraction osteogenesis model and prevent the occurrence of osteoporosis.