Paulus Alexander Christoph, Franke Manja, Kraxenberger Michael, Schröder Christian, Jansson Volkmar, Utzschneider Sandra
Department of Orthopedic Surgery, University Hospital of Munich (LMU), Campus Großhadern, Marchioninistraße 15, 81377 Munich, Germany.
Biomed Res Int. 2015;2015:575849. doi: 10.1155/2015/575849. Epub 2015 Mar 19.
Overlooked polymethylmethacrylate after unicondylar knee arthroplasty can be a potential problem, since this might influence the generated wear particle size and morphology. The aim of this study was the analysis of polyethylene wear in a knee wear simulator for changes in size, morphology, and particle number after the addition of third-bodies.
Fixed bearing unicondylar knee prostheses (UKA) were tested in a knee simulator for 5.0 million cycles. Following bone particles were added for 1.5 million cycles, followed by 1.5 million cycles with PMMA particles. A particle analysis by scanning electron microscopy of the lubricant after the cycles was performed. Size and morphology of the generated wear were characterized. Further, the number of particles per 1 million cycles was calculated for each group.
The particles of all groups were similar in size and shape. The number of particles in the PMMA group showed 10-fold higher values than in the bone and control group (PMMA: 10.251 × 10(12); bone: 1.145 × 10(12); control: 1.804 × 10(12)).
The addition of bone or PMMA particles in terms of a third-body wear results in no change of particle size and morphology. PMMA third-bodies generated tenfold elevated particle numbers. This could favor an early aseptic loosening.
单髁膝关节置换术后残留的聚甲基丙烯酸甲酯可能是一个潜在问题，因为这可能会影响产生的磨损颗粒大小和形态。本研究的目的是分析膝关节磨损模拟器中聚乙烯磨损情况，观察添加第三体后磨损颗粒在大小、形态和数量上的变化。
在膝关节模拟器中对固定承重单髁膝关节假体（UKA）进行500万次循环测试。先添加骨颗粒进行150万次循环，然后添加聚甲基丙烯酸甲酯颗粒进行150万次循环。循环结束后，通过扫描电子显微镜对润滑剂中的颗粒进行分析，表征产生的磨损颗粒的大小和形态。此外，计算每组每100万次循环的颗粒数量。
所有组的颗粒在大小和形状上相似。聚甲基丙烯酸甲酯组的颗粒数量比骨颗粒组和对照组高10倍（聚甲基丙烯酸甲酯组：10.251×10¹²；骨颗粒组：1.145×10¹²；对照组：1.804×10¹²）。
添加骨颗粒或聚甲基丙烯酸甲酯颗粒导致第三体磨损时，颗粒大小和形态没有变化。聚甲基丙烯酸甲酯第三体产生的颗粒数量增加了10倍。这可能会促进早期无菌性松动。
