Davidson J A, Poggie R A, Mishra A K
Orthopaedic Research Department, Smith & Nephew Richards Inc., Memphis, TN 38116.
Biomed Mater Eng. 1994;4(3):213-29.
The debris generated by the progressive wear of total joint replacement (TJR) devices is considered a primary cause of osteolysis, bone resorption, and premature failure of artificial hips and knees. The vast majority of this debris originates from the UHMWPE articulating surfaces caused by tribological interaction with the opposing metal or ceramic surface and hard particulates contained in the sinovial fluid. Entrapment of third body debris, such as cortical bone, PMMA cement, and titanium debris, between the articulating surfaces can cause abrasion of both the hard bearing surface and the UHMWPE. The propensity for abrasive wear is dependent on the relationship between the hardness of the third-body debris and the hardness of the bearing surfaces. To gain a better understanding of this relationship and its effect on wear, the abrasive wear behavior of several metal and ceramic bearing surfaces was characterized in terms of the hardness of both the third-body debris and the metal or ceramic substrate. The effects of abrasion and increased surface roughness of the metal or ceramic surfaces on wear of the UHMWPE was also determined. In addition, the amount of UHMWPE wear was quantified in terms of the amount (particles/ml) of titanium fretting-type debris contained in solution. The results of this investigation showed the resistance to abrasive wear of the metal and ceramic bearing surfaces to increase with increasing surface hardness. Bone debris, PMMA cement, and titanium debris produced visible abrasion of all metal surfaces including nitrogen ion implanted Ti-6Al-4V. The ceramic bearing surfaces showed no evidence of abrasion and produced the least amount of UHMWPE wear. The wear of UHMWPE sliding against Co-Cr-Mo was found to increase with increasing levels of 1.48 microns titanium debris added to the wear test solution. The rate of UHMWPE wear increased rapidly for concentrations of titanium debris in the test solution exceeding about 10(5) particles/ml. These test results suggest that third-body particles, both large and small, are capable of causing increased abrasive wear of UHMWPE, and that abrasion of the hard bearing surfaces will occur if the hardness of the third-body debris exceeds the hardness of the metal or ceramic bearing surface.
全关节置换（TJR）装置渐进性磨损产生的碎屑被认为是骨溶解、骨吸收以及人工髋关节和膝关节过早失效的主要原因。这些碎屑绝大多数源自超高分子量聚乙烯（UHMWPE）关节表面，是由其与相对的金属或陶瓷表面的摩擦学相互作用以及滑液中所含的硬颗粒导致的。关节表面之间夹入第三体碎屑，如皮质骨、聚甲基丙烯酸甲酯（PMMA）骨水泥和钛碎屑，会导致硬支承表面和UHMWPE都出现磨损。磨料磨损的倾向取决于第三体碎屑硬度与支承表面硬度之间的关系。为了更好地理解这种关系及其对磨损的影响，根据第三体碎屑以及金属或陶瓷基底的硬度，对几种金属和陶瓷支承表面的磨料磨损行为进行了表征。还确定了金属或陶瓷表面的磨损和表面粗糙度增加对UHMWPE磨损的影响。此外，根据溶液中所含钛微动型碎屑的量（颗粒/毫升）对UHMWPE的磨损量进行了量化。这项研究的结果表明，金属和陶瓷支承表面的抗磨料磨损能力随表面硬度的增加而增强。骨碎屑、PMMA骨水泥和钛碎屑对包括氮离子注入的Ti-6Al-4V在内的所有金属表面都产生了明显磨损。陶瓷支承表面没有磨损迹象，并且产生的UHMWPE磨损量最少。发现UHMWPE与钴铬钼合金对磨时，随着添加到磨损试验溶液中的1.48微米钛碎屑水平的增加，UHMWPE的磨损也增加。当试验溶液中钛碎屑的浓度超过约10⁵颗粒/毫升时，UHMWPE的磨损速率迅速增加。这些试验结果表明，无论大小，第三体颗粒都能够导致UHMWPE的磨料磨损增加，并且如果第三体碎屑的硬度超过金属或陶瓷支承表面的硬度，硬支承表面就会出现磨损。
