用组织工程方法修复山羊胫骨骨缺损的实验研究

EXPERIMENTAL STUDY OF CAPRINE TIBIA DIAPHYSEAL DEFECT REPAIRED WITH THE TISSUE ENGINEERING METHOD

制备组织工程用山羊胫骨骨缺损模型 ,研究用组织工程的方法修复山羊胫骨骨缺损的可行性。2 7只中国青山羊制备单侧胫骨中段 2 0mm的骨膜与骨缺损 ,7孔钢板内固定 ,随机分 3组 :空白组不进行植入处理 ;对照组 (CHAP组 )单纯植入羟基磷灰石 (CHAP) ;实验组 (CHAP/BMSc组 )植入CHAP与骨髓基质细胞 (BMSc)的复合物。术后 4、8、12周放射学检查X线片光密度指数比值、组织学方法评价各组骨缺损修复情况 ,12周CHAP/BMSc组与CHAP组做压应变与三点弯曲实验 ,评价骨缺损修复后的生物力学性质。结果显示 ,术后4、8、12周X线片光密度指数比值空白组无明显变化 ,CHAP组低于CHAP/BMSc组 (P <0 0 5 ) ;组织学切片显示CHAP/BMSc组成骨较CHAP组早、多 ;12周三点弯曲实验载荷、弯曲应力CHAP/BMSc组高于C组 (P <0 0 5 )。提示山羊胫骨 2 0mm骨与骨膜缺损不能自行修复 ,可满足骨组织工程大动物实验需要 ;CHAP与BMSc复合修复骨缺损在成骨时间、成骨量与质量上均优于单纯CHAP。

To prepare an experimental caprine model of tibia bone diaphyseal defect used in tissue engineering and defect repair with the tissue engineering method, 27 Chinese caprines were divided into 3 groups: blank, control, and test. The 20mm left tibia diaphyseal defect of each caprine was made and fixed with plates. The blank group was not filled with coral hydroxyapatite (CHAP) or bone marrow stroma cell (BMSc). The control group and the experimental group were filled with CHAP and CHAP/BMSc respectively. The results of three groups were evaluated by X ray examination, optical density index of X ray film and histology 4, 8, 12 weeks after operation. The biomechanical characteristics of the specimens of the CHAP group and the CHAP/BMSc group were tested by three point bending test 12 weeks after operation.The results showed that the optical density indices of X ray film of the blank group were not significantly different 4, 8, 12 weeks after operation and indices of the CHAP group were significantly smaller than those of the CHAP/BMSc group ( P <0 05). More bones were found in the experimental group as compared with the control group. The loads and bending stresses of the CHAP/BMSc group were remarkably higher than those of the CHAP group. The results demonstrate that the caprine model of 20mm tibia diaphyseal defect can't be repaired by caprine itself, but can satisfy the tissue engineering's demands. The effect of BMSc in combination with CHAP on the repair of bone defect is better than that of CHAP alone both in quantity and quality of bone formation.