摘要
目的观察采用应力松弛接骨板固定对骨折愈合的影响及机制。方法对２４只新西兰免两侧胫骨干截骨，分别采用应力松弛接骨板和坚硬接骨板固定，术后２、４及８周采用核酸原位杂交技术和透射电镜观察骨折愈合过程中骨痂胶原ｍＲＮＡ的表达及细胞超微结构变化。结果骨折后２周，应力松弛接骨板组骨痂内见较多功能活跃的成骨细胞和成软骨细胞，分别表达Ⅰ型和 Ⅱ型胶原ｍＲＮＡ；４周时成骨细胞数量明显增加，功能更加活跃， Ｉ型胶原表达水平也达到高峰。此时活跃的破骨细胞开始出现； ８周时仍可见到较多功能活跃的成骨细胞、破骨细胞及Ⅰ型胶原ｍＲＮＡ表达。而坚硬接骨板组２、４周时，成骨细胞数量及功能均不及应力松弛接骨板组；８周时破骨细胞功能活跃，伴有相邻骨细胞骨溶解现象。结论应力松弛接骨板的应力松弛作用，促进了局部间充质细胞向成骨细胞和成软骨细胞分化，并且高水平表达 Ⅰ、Ⅱ血型胶原 ｍＲＮＡ，有利于骨痂改建的顺利进行。
To investigate the influence of stress-relaxation plate on fracture healing and its mechanism. Methods Twenty－four New Zealand rabbits were used in this study. Bilateral tibia were osteotomized in the middle and fixed with stress-relaxation plate (group SRP) and rigid plate (group RP) respectively. The transmission electron microscopy (TEM) examination and analysis of collagen mRNA expression in situ hybridization were compared between SRP group and RP group during 2-8 weeks postoperatively. Results In SRP group, the TEM observation and in situ hybridization study showed that a great number of osteoblasts and chondroblasts with high functional activity emerged and expressed high levels of type Ⅰ andⅡ collagen mRNA respectively 2 weeks after operation. By 4 weeks after fracture, more and more osteoblasts appeared without chondroblasts, the level of expressing type I collagen mRNA also amounted to a peak. The active osteoclasts also emerged at this time. These signs continued until 8 weeks postoperatively. While in RP group, no chondroblasts could be seen at the early stage of fracture, both the number and functional activity of osteoblasts were lower than those of the SRP group. By 8 weeks after implantion, the osteoblasts were seldom found, meanwhile, the osteoclasts become more active accompanied with signs of osteocytic osteolysis, which indicate the prevailed resorption process in the remodelling stage. In addition, there were only expression of type I collagen mRNA during the different periods after operation, and the level of expression was lower than that of the SRP group. Conclusion Stress-relaxation of SRP stimulates the osteogenetic cells differentiated into osteoblast and chondroblast, which express high level of type Ⅰ and type Ⅱ collagen mRNA respectively; it also benefits callus remodelling.
出处
《中华骨科杂志》
CAS
CSCD
北大核心
2000年第6期362-365,共4页
Chinese Journal of Orthopaedics
基金
国家自然科学基金!(39470698)
