Landry M E, Blanchard C R, Mabrey J D, Wang X, Agrawal C M
Department of Orthopaedics, Orthopaedic Bioengineering, The University of Texas Health Science Center, San Antonio, USA.
J Biomed Mater Res. 1999 Spring;48(1):61-9. doi: 10.1002/(sici)1097-4636(1999)48:1<61::aid-jbm11>3.0.co;2-u.
Osteolysis in total joint replacements has been linked to ultrahigh molecular weight polyethylene (UHMWPE) wear particles. Although the biological response to these UHMWPE particles is poorly understood at present, it has been demonstrated that particle size and morphology are important factors in such a response. The goal of the present study was twofold: to develop a comprehensive set of particle size and shape descriptors, and to use these descriptors to analyze the effects of different contact conditions and material parameters during the wear process on the size and morphology of UHMWPE wear debris. The three parameters studied were average contact stress (6.9 and 13.8 MPa), macromolecular orientation of the UHMWPE with respect to the wear direction (0 degrees , 45 degrees , and 90 degrees ), and UHMWPE initial surface roughness (Ra = 1 and 3 microm). Tests were performed using pin on disk or cylinder on plate systems for 3 million cycles each. The results indicated that the initial surface roughness of the UHMWPE test samples had no effect on the morphology of UHMWPE wear particles. However, particle size and morphology were a function of the average contact stress and molecular orientation of the UHMWPE.
全关节置换中的骨溶解与超高分子量聚乙烯（UHMWPE）磨损颗粒有关。尽管目前对这些UHMWPE颗粒的生物学反应了解甚少，但已证明颗粒大小和形态是这种反应的重要因素。本研究的目标有两个：开发一套全面的颗粒大小和形状描述符，并使用这些描述符分析磨损过程中不同接触条件和材料参数对UHMWPE磨损碎屑的大小和形态的影响。研究的三个参数是平均接触应力（6.9和13.8兆帕）、UHMWPE相对于磨损方向的大分子取向（0度、45度和90度）以及UHMWPE初始表面粗糙度（Ra = 1和3微米）。使用销盘或柱板系统进行测试，每个系统进行300万次循环。结果表明，UHMWPE测试样品的初始表面粗糙度对UHMWPE磨损颗粒的形态没有影响。然而，颗粒大小和形态是UHMWPE平均接触应力和分子取向的函数。
