Bennett D B, Orr J F, Baker R
School of Mechanical and Manufacturing Engineering, The Queens University of Belfast, Northern Ireland.
J Arthroplasty. 2000 Oct;15(7):909-15. doi: 10.1054/arth.2000.9195.
Wear of ultra-high-molecular-weight polyethylene (UHMWPE) and the subsequent adverse tissue reaction to the wear particles has been cited as the predominant problem affecting total joint arthroplasties. Wear of the UHMWPE acetabular cup in total hip arthroplasties (THAs) is influenced by the sliding distance and direction of individual points on the femoral head, which has as yet been ascertained only for normal subjects. This study seeks to determine the trajectory of specified points on the femoral head for individual THA patients and the distances traversed by these points. A computer program was designed to use gait data from THA patients to simulate the motion of these points. Gait analysis was performed on 19 THA patients at a period of 5 years after operation. The orientation of the acetabular cup was ascertained from radiographs to determine the position of the points on the head most involved in the wear process. The loci of the points differed widely in size, shape, and direction between subjects. The largest average distance traversed was 140% greater than the smallest average distance traversed. Shorter longitudinal paths would tend to cause less wear than larger, wider paths, which cross a greater number of adjacent paths.
超高分子量聚乙烯（UHMWPE）的磨损以及随后对磨损颗粒产生的不良组织反应，被认为是影响全关节置换术的主要问题。在全髋关节置换术（THA）中，UHMWPE髋臼杯的磨损受股骨头各点滑动距离和方向的影响，而目前仅在正常受试者中确定了这一点。本研究旨在确定个体THA患者股骨头特定点的轨迹以及这些点所经过的距离。设计了一个计算机程序，利用THA患者的步态数据来模拟这些点的运动。对19例THA患者在术后5年进行了步态分析。通过X线片确定髋臼杯的方向，以确定头部磨损过程中最相关点的位置。不同受试者之间，这些点的轨迹在大小、形状和方向上差异很大。所经过的最大平均距离比最小平均距离大140%。较短的纵向路径往往比较大、较宽且穿过更多相邻路径的路径产生的磨损更少。
