Development of Optimun Design, Trial Production and Evaluation Systems for Knee Joint Prostheses with High Performace Similar to Natural Synovial Joints

本研究的目的是开发高性能膝关节假体的优化设计、试制和评估系统。采用了以下方法。【自然膝关节三维几何分析及膝关节假体几何设计的提出】通过激光位移仪或磁共振成像对自然膝关节模型进行几何测量，进行几何分析。在几何分析的基础上，提出了以最小应变能为目标的自适应曲面重构设计。提出了双圆柱形设计，以提高行走过程中形成的液膜的回收率。【试制与评价】采用个人电脑控制的数控机床，以丙烯酸树脂和超高分子量聚乙烯为原料，生产出圆柱形、双圆柱形、球形和重塑模型。部分部件由不锈钢制成。人工膝关节采用PVA（聚乙烯醇）水凝胶、半互穿网状水凝胶或硅橡胶。观察了这些模型的流体膜形成和摩擦行为。仿真试验验证了自适应曲面重构和双圆柱设计的有效性。椭圆连接膝关节假体在柔面横向设计上具有优势。现有解剖设计膝关节假体的磨损试验表明，摩擦学严重程度控制着磨损模式。应用电影x线摄影技术对患者膝关节假体进行运动分析。【自适应多模态润滑的优化设计】本课题的研究总结提出了膝关节假体自适应多模态润滑的设计理念。结果表明，采用较好的一致性几何设计或适当的半径设计，以及采用具有边界润滑能力的柔顺材料均可提高润滑性能。用原子力显微镜（AFM）观察了蛋白质分子对边界的润滑作用。为临床应用指明了设计方向。少

The object of this research is to develop the systems for optimum design, trial production and evaluation of knee prostheses with high performance.The following method were carried out.[Three-dimensional geometrical analysis of natural knee joints and proposition of geometrical design for knee prostheses] Geometrical analysis was carried out based on geometrical measurement of natural knee joint model by laser displacement meter or Magnetic Resonance Images. On the basis of geometrical analysis, adaptive surface remodeling design was proposed by minimizing the strain energy during walking motion. Duo-cylindrical design was proposed to improve the recovery of fluid film formation during walking motion.[Trial production and evaluation] Cylindrical, duo-cylindrical, spherical and remodeling models were produced from acrylic resin and ultrahigh molecular weight polyethylene by personal computer controlled NC machine. Some components were prepared from stainless steel. The artificial cartil … More age of PVA (polyvinylalcohol) hydrogel, semi-interpenatrating network hydrogel or silicone rubber were applied for knee prostheses. Fluid film formation and frictional behavior for these models were observed. Effectiveness of adaptive surface remodeling and duo-cylindrical design was evaluated in simulatot test. The knee prostheses of elliptical conjunction showed superiority in transverse design for compliant surface. The wear tests of existing knee prostheses of anatomical design exhibited that the tribological severity controls wear modes. Cine-radiography was applied for the motion analysis of knee prostheses in patients.[Optimun design with adaptive multimode lubrication] The design concept of adaptive multimode lubrication for knee prostheses was proposed from the summarization of this research project. It was shown that geometrical design with better congruity or with appropriate radius, and the application of compliant materials accompanied with boundary lubricating ability enhance the lubricating performance. The boundary lubrication by protein molecules was examined by atomic force microscopy (AFM) .The design direction was shown for clinical application. Less