聚乙烯颗粒对植入体周成骨的影响

Effect of UHMWPE Particles on Bone Formation Around an Implant

目的 观察聚乙烯颗粒对植入体周成骨的作用。方法 建立植入体无菌松动的动物模型 ,定期向连通植入体 -骨界面的关节腔内注射聚乙烯 (UHMWPE)颗粒。结果 植入体周骨小梁表面碱性磷酸酶 (AL P)阳性染色的细胞减少 ;植入体表面骨结合率术后 6周为 15 .0 6 %± 1.70 % ,12周为 18.38%± 2 .4 9% ,2 0周为 2 4 .2 0 %± 3.6 8% ,显著低于同期对照组 (P<0 .0 5 ) ;植入体周骨小梁密度术后 6周为 2 0 .4 5 %± 7.79% ,12周为 19.16 %± 7.77% ,2 0周为 15 .74 %± 9.0 5 % ,6周时其与对照组相比无显著性意义 (P>0 .0 5 ) ,而在 12、2 0周时二者差异有显著性意义 (P<0 .0 5 )。结论 聚乙烯 (UHMWPE)颗粒在髓腔内植入体周微环境中阻碍新骨形成。

Objective To observe the effect of UHMWPE particles on bone formation adjacent to an implant in intramedullary canal circumstances. Methods In vivo study two cylindrical implants with smooth surface made of Ti-A were placed into distal femur and proximal tibia stems of rabbit via its knee, UHMWPE particles were injected repeatedly into rabbit knee connecting to the implant-bone interface at definite intervals. Results The amount of alkaline phophatase(ALP)positive cells decreased gradually and osteocytes disappeared from the bony lacunae in trabeculae somewhere. The percentage of the implante surface that has new bone in direct contact with the implant(Bone Ongrowth)was 15.06%±1.70%, 18.38%±2.49%, 24.20%±3.68% 6, 12, 20 weeks after operation respectively, the percentage of new bone in the initial gap(Bone-Gap Healing or Trabecular Density) was 20.45%±7.79%, 19.16%±7.77%, 15.74%±9.05% 6, 12, 20 weeks after operation respectively. Apart from Bone-Gap Healing after 6 weeks. They all had significant difference( P <0.05) in each time group. Conclusion UHMWPE particles showed negative effects on bone formation adjacent to an implant in intramedullary canal circumstances.