Saikko V O
Helsinki University of Technology, Laboratory of Machine Design, Espoo, Finland.
Acta Orthop Scand. 1995 Dec;66(6):501-6. doi: 10.3109/17453679509002302.
Ultra-high molecular weight polyethylene acetabular cups backed by Ti-6Al-4V acetabular shells were articulated against Co-Cr-Mo alloy, ion-implanted Co-Cr-Mo alloy, and zirconia ceramic femoral heads in a hip joint simulator. Three tests of three million walking cycles each were run with five different head-cup combinations. The wear of the cups was measured gravimetrically at half a million cycle intervals. When the thickness of the cup was 10.9 mm, the mean wear rate was 0.14 mm/year against 28 mm dia. Co-Cr-Mo heads and 0.09 mm/year against ion-implanted 28 mm Co-Cr-Mo heads. When the thickness of the cup was 7.0 mm, the mean wear rate was 0.04 mm/year against 28 mm zirconia heads, but when the thickness was 10.9 mm, no wear occurred against 28 and 32 mm zirconia heads. The results indicate that a significant reduction in the wear of the polyethylene cup can be expected if zirconia is used as the head material, instead of Co-Cr-Mo alloy or ion-implanted Co-Cr-Mo alloy. The diameter of the zirconia head, 28 vs. 32 mm, seems unimportant, but a cup thickness much below 10 mm may be disadvantageous.
在髋关节模拟器中，将由Ti-6Al-4V髋臼壳支撑的超高分子量聚乙烯髋臼杯与钴铬钼合金、离子注入钴铬钼合金和氧化锆陶瓷股骨头进行铰接。使用五种不同的头杯组合进行了三项测试，每项测试三百万次行走循环。每隔五十万次循环通过重量法测量髋臼杯的磨损。当髋臼杯厚度为10.9毫米时，相对于直径28毫米的钴铬钼股骨头，平均磨损率为每年0.14毫米；相对于离子注入的直径28毫米的钴铬钼股骨头，平均磨损率为每年0.09毫米。当髋臼杯厚度为7.0毫米时，相对于直径28毫米的氧化锆股骨头，平均磨损率为每年0.04毫米，但当厚度为10.9毫米时，相对于直径28毫米和32毫米的氧化锆股骨头未发生磨损。结果表明，如果使用氧化锆作为股骨头材料，而不是钴铬钼合金或离子注入钴铬钼合金，可以预期聚乙烯髋臼杯的磨损会显著降低。氧化锆股骨头的直径（28毫米与32毫米）似乎并不重要，但髋臼杯厚度远低于10毫米可能是不利的。
