Laska Anna, Archodoulaki Vasiliki-Maria, Duscher Bernadette
Institute of Materials Science and Technology, Vienna University of Technology, Getreidemarkt 9, A-1060 Vienna, Austria; Institute of Materials Science and Engineering, Lodz University of Technology, Stefanowskiego 1/15, 90-924 Lodz, Poland.
Institute of Materials Science and Technology, Vienna University of Technology, Getreidemarkt 9, A-1060 Vienna, Austria.
J Mech Behav Biomed Mater. 2016 Aug;61:70-78. doi: 10.1016/j.jmbbm.2016.01.007. Epub 2016 Jan 19.
Ultra-high molecular weight polyethylene (PE-UHMW) acetabular liners have a limited lifespan in a patient's body. There are many factors affecting the performance of the implant and furthermore the properties of the polymeric material are changing after implantation. In this work material changes according to structure and morphology and their implication on mechanical properties are in focus. The physical and mechanical properties of ten crosslinked (xL) PE-UHMW and nine conventional (conv) gamma-sterilized PE-UHMW hip components, used as sliding surface in total hip joint replacement, with different in-vivo times are compared. The evaluation of the retrieved acetabular liners is performed in view of crosslinking and conventional gamma-sterilization but also in terms of the influence of gender concerning alteration in properties. The oxidative degradation in the PE-UHMW is investigated by means of Fourier Transformed Infrared Spectroscopy (FTIR). The characterization of the morphology is carried out via differential scanning calorimetry (DSC). A depth profile of the micro-hardness and elastic modulus is taken over the cross-section of the components in order to find the influence of chemical constitution and morphology on the micro-mechanical properties. It could be shown that crosslinking and oxidative degradation influence the degree of crystallinity of the polymer. Oxidation occurs for both types of the material due to in-vivo time. Higher degree of crystallinity can be correlated to higher hardness and indentation modulus. No unequivocal superiority of crosslinked over conventional liners can be observed. The influence of sex concerning alteration of the evaluated properties matters but need to be further investigated.
超高分子量聚乙烯（PE-UHMW）髋臼衬垫在患者体内的使用寿命有限。影响植入物性能的因素众多，而且植入后聚合物材料的性能会发生变化。在这项工作中，重点关注材料根据结构和形态的变化及其对机械性能的影响。比较了十种交联（xL）PE-UHMW和九种常规（conv）γ射线灭菌的PE-UHMW髋关节组件的物理和机械性能，这些组件在全髋关节置换中用作滑动表面，且体内使用时间不同。对回收的髋臼衬垫的评估是从交联和常规γ射线灭菌的角度进行的，同时也考虑了性别对性能变化的影响。通过傅里叶变换红外光谱（FTIR）研究PE-UHMW中的氧化降解。通过差示扫描量热法（DSC）对形态进行表征。在组件的横截面上获取微硬度和弹性模量的深度分布，以找出化学组成和形态对微机械性能的影响。结果表明，交联和氧化降解会影响聚合物的结晶度。由于体内时间的原因，两种材料都会发生氧化。较高的结晶度与较高的硬度和压痕模量相关。未观察到交联衬垫相对于传统衬垫有明确的优势。性别对评估性能变化的影响是存在的，但需要进一步研究。
