人工髋关节假体磨损性能的研究现状

Wearing performance of artificial hip joint

聚乙烯用于人工髋、膝等关节置换材料已有40多年的历史,具有低的摩擦因数和磨损率、良好的机械性能及生物相容性。但聚乙烯磨损颗粒引起的局部界面骨溶解,导致假体无菌松动,是造成人工髋关节置换失败的主要原因。为了提高人工髋关节的摩擦性能,新的关节假体组合界面,如金属对金属、陶瓷对陶瓷引起了研究者的关注。金属对金属人工髋关节的线性摩擦率只相当于金属对普通超高分子聚乙烯的百分之一,但金属对金属人工髋关节存在应力遮挡效应,同时期释放的金属离子具有潜在的毒性。陶瓷材料具有良好的生物相容性、摩擦系数低,磨损小,耐磨力强,但陶瓷内衬断裂影响了陶瓷对陶瓷人工髋关节的长期效果。进一步改善材料的功能适应性,探索新的髋关节假体材料表面改性的方法,对人体髋关节生物摩擦行为和润滑机制进行研究是目前研究的主要问题。

Polyethylene has been used as materials for artificial hip or knee for more than 40 years. It has low friction factor, wear rate, good mechanical function and biocompatibility. However, polyethylene wearing particle-caused local interface osteolysis, resulting in aseptic loosening is the primary reason for artificial hip replacement failure. To improve friction performance of artificial hip joint, joint prosthesis assembly interface such as metal to metal and ceramics to ceramics has arouse more attention. Linear friction rate of metal to metal artificial hip is one percent of metal to ultrahigh molecular polyethylene, but metal to metal artificial hip joint has stress shielding effect and potential toxicity. Ceramics has good biocompatibility, low friction coefficient, and wear-resistance, but lined ceramics breakage affects long-term effect of ceramics to ceramics artificial hip joint. To improve material function, explore prosthesis surface modification, and know biological friction and lubrication mechanism are important issues in current studies.