聚乙烯醇水凝胶弹性体复合物修复关节软骨缺损的实验研究

A study on repair of the defects of articular cartilage with polyvinyl alcohol hydrogel elastomers composite device

目的:研究应用聚乙烯醇水凝胶弹性体复合物作为关节软骨替代物修复成年犬的关节软骨缺损。方法:取8只成年犬随机均分为A、B两组,每组4只。在犬双后肢膝关节股骨内髁负重面制造软骨缺损区,在缺损区植入同等大小的聚乙烯醇水凝胶弹性体复合物。手术后8周和24周分别将A、B两组实验动物处死取材。在肉眼和光镜下观察植入物周围的软骨和软骨下骨,对应的半月板和胫骨面的软骨组织。结果:大体观察,实验动物术后关节功能良好,植入物在8周和24周均未见松动和脱落,与软骨下骨牢固结合。植入物周围软骨和对应部位的半月板和胫骨面软骨未见退变表现。光镜下观察8周和24周植入物周围未见软骨组织退变表现;软骨下骨组织长入钛纤维网孔隙中,形成生物力学固定;植入物周围无淋巴细胞浸润。结论:聚乙烯醇水凝胶弹性体具有与关节软骨类似的物理特性和良好的生物相容性,能作为关节软骨替代物修复关节软骨的缺损,恢复关节面的完整,维持关节功能。

Objective:To investigate the use of polyvinyl alcohol hydrogel elastomers composite device as the substitute of articular cartilage to repair the defects in dogs.Method:Eight mature adult mongrel dogs were randomly divided into two groups. Both hind legs of each dog were operated to make defects of cartilage in the load-bearing portions of the medial femoral condyles. The polyvinyl alcohol hydrogel elastomers composite device was implanted in the defects afterward. Four dogs were sacrificed in 8 weeks and others were killed in 24 weeks postoperatively. The cartilage around the implant, the subchondral bone, the menisci and the tibial joint surface were observed with light microscopes.Result:The range of motion of each animal′s knee joint was almost normal after operation. All of the implants attached firmly to the underlying bone through bone ingrowth into the pores of the titanium fiber mesh after 8 and 24 weeks. There were not any lymphocyte infiltration around the implants and no cartilage degeneration. Conclusion: The polyvinyl alcohol hydrogel elastomers have good lubrication properties, adequate shock-absorbing ability, high wear resistance and good biocompatibility, which is similar to the properties of the articular cartilage. The composite device became firmly attachedy to the host bone as a result of bone penetration through the pores of the titanium fiber mesh substrate. It could be used as artificial articular cartilage to repair the defects of cartilage.Author′s address Department of Orthopaedics, the Third Hospital, Peking University,Beijing,100083