不同方向关节软骨缺损时软骨修复及膝关节运动功能恢复有无差异?

Cartilage repair and motor function recovery in knee joint during articular cartilage defects at different directions

背景:目前关于关节软骨缺损修复的研究方法较多,其中微骨折技术已得到普遍应用。目的:观察不同方向(冠状位与矢状位)关节软骨缺损时膝关节运动功能恢复及组织修复形态学变化情况。方法:建立兔膝关节股骨内侧髁全厚2 mm关节软骨缺损模型,根据切口方向分为冠状位组与矢状位组。分别在造模5,10,20周时行大体观察,取标本做石蜡切片后行苏木精-伊红染色、胶原蛋白染色,并应用光学显微镜和免疫组织学检查观察关节软骨缺损处的组织修复情况。造模后定期检查2组兔的关节活动度。结果与结论:2组缺损处均可见越过股骨髁的一条白线,缺损修复的关节面与原位软骨平齐,并达到了骨性愈合,手术处理的膝关节对功能无影响。光学显微镜下2组均可见软骨下骨的部分重建,主要由纤维软骨修复,骨重建的水平低于邻近的原位软骨的潮线。免疫组织学检查可见2组标本的缺损处均呈现Ⅰ型胶原染色逐步减弱,Ⅱ型胶原染色逐步增强。提示不同方向(冠状位与矢状位)关节软骨缺损的组织修复及膝关节运动功能恢复无明显差异。

BACKGROUND： At present, there are many researches about repairing articular cartilage defects. In particular, the microfracture technique has been widely used. OBJECTIVE： To observe recovery of knee joint motor function and morphological changes in tissue repair during articular cartilage defects with different directions （coronal position and sagittal position）. METHODS： Articular cartilage fracture models with 2 mm-thick medial femoral condyles of rabbit knee joint were established. According to incision directions, models were assigned to coronal and sagittal groups. At 5, 10 and 20 weeks after model induction, general observation was performed. Specimens were sliced into paraffin sections, and subjected to hematoxylin-eosin staining and collagen staining. Tissue repair at the articular cartilage defects was observed using optical microscope and immunohistochemical method. After model induction, range of motion of rabbit joints was regularly examined in the two groups. RESULTS AND CONCLUSION： A white line was seen across the femoral condyles at defects in the two groups. Articular surface at defect repair was at the level of in situ cartilage, and reached a bone union. Knee joint treated by operation did not affect function. Under light microscope, partial reconstruction of subchondral bone was seen in the two groups, mainly fibrocartilage repair. The level of bony remodeling was lower than tidal line of adjacent in situ cartilage. Immunohistochemical method exhibited that type I collagen staining gradually reduced at defects of specimens, but type II collagen staining gradually increased. These results suggested that there was no significant difference in the recovery of motor function of knee joint and the repair of articular cartilage with different directions （coronal and sagittal position）.