BACKGROUND:Cartilage scaffold plays an important role in articular cartilage injury, but it is stil restricted in practice, leading to the repair failure using tissue-engineered cartilage. OBJECTIVE:To explore the preparation method of cartilage scaffold with directional structure and its repairing effect in cartilage injury of rabbits. METHODS:Directional cartilage scaffolds were prepared by temperature gradient induced phase separation technique. The cross-linking of cartilage scaffold was completed with genipin. The physical and mechanical properties of scaffolds were determined. Forty-eight white rabbits were modeled into exercised-induced articular cartilage injury and equivalently randomized into two groups, fol owed by implantation of non-directional or directional scaffolds. Samples were col ected at postoperative 6, 12 and 24 weeks to compare the repair effect of two scaffolds on rabbit joint injury. RESULTS AND CONCLUSION:Scanning electron microscope showed that the regular microstructures on the longitudinal section of directional scaffolds were aligned in the same direction, while the longitudinal and transverse planes of the non-directional scaffolds showed porous honeycomb structures. The elastic modulus of the directional scaffold was significantly higher than that of the non-directional scaffold (P<0.05). O’Driscol histological scores in the directional scaffold group were significantly higher than those in the non-directional scaffold group at 6, 12 and 24 weeks postoperatively (P<0.05). At postoperative 24 weeks, in the directional scaffold group, the three-dimensional reconstruction of the rabbit defect region was flat and smooth, and coronal two-dimensional scanning showed the cartilage thickness of the newborn cartilage was very close to that of the normal bone;the cartilage surface in the non-directional rabbits was flat under three-dimensional CT, and coronal two-dimensional scanning showed that the repaired cartilage was almost the same as the normal cartilage. Hematoxylin-eosin staining showed that at 24 weeks postoperatively, the defect site disappeared and the cartilage cel s arranged in the vertical direction in the directional scaffold group. There were typical cartilage lacunae at the defect site in the non-directional scaffold group at 24 weeks postoperatively. Our findings suggest that the directional cartilage scaffold prepared using temperature gradient induced phase separation technique holds good physical and mechanical properties, and its implantation into the rabbit articular cartilage injury induced by exercise can promote the injury repair to obtain ideal mechanical properties.%背景：软骨支架材料虽然在运动关节软骨损伤中发挥了重要的作用，但是在实际开展过程中仍受到较多的限制，导致组织工程化软骨修复达不到预期目标。目的：探讨定向结构软骨支架材料制备方法及在大白兔运动关节软骨损伤中的修复效果。方法：利用温度梯度热诱导相分离技术制备定向结构软骨支架材料，采用京尼平完成对软骨支架材料的交联，并测定支架材料的物理、力学性能。48只大白兔建立运动关节软骨损伤模型，随机将大白兔分为非定向支架组和定向支架组(n=24)，分别于运动关节软骨损伤处植入非定向支架和定向支架，6，12，24周后取材，比较2种支架在大白兔运动关节损伤中的修复效果。结果与结论：①扫描电镜观察：定向支架组纵切面上可见排列相对整齐的微管样结构，且方向一致；而非定向支架组纵切面与横切面表现为多孔蜂窝状结构；②弹性模量：定向支架组支架材料弹性模量显著高于非定向支架组(P<0.05)；③O'Driscoll量表评分：定向支架组大白兔术后6，12，24周显微CT下O'Driscoll量表评分显著高于非定向支架组(P<0.05)；④CT扫描：术后24周定向支架组大白兔CT下三维重建可见缺损部位平坦、光滑，冠状面二维扫面可见新生类软骨厚度与周围正常骨十分接近；非定向组大白兔3D下显示软骨表面比较平整，冠状面2D显示修复软骨与正常软骨基本相同；⑤苏木精-伊红染色：定向支架组术后24周缺损部位消失，软骨细胞呈垂直方向排列；非定向支架组术后24周缺损部位存在典型软骨陷窝，与周围软骨组织存在差异；⑥结果提示，采用温度梯度热诱导相分离技术制备的定向微管结构软骨支架具有良好的物理、力学性能，将其植入大白兔运动关节损伤软骨中能促进损伤部位修复，获得理想的机械力学性能。
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