Shiramizu Kei, Vizesi Frank, Bruce Warwick, Herrmann Sebastian, Walsh William R
Surgical & Orthopaedic Research Laboratories, Prince of Wales Hospital, University of New South Wales, Randwick, NSW, Australia.
Int Orthop. 2009 Apr;33(2):403-6. doi: 10.1007/s00264-007-0478-7. Epub 2007 Nov 22.
The tibiofemoral articulating interfaces of six high flexion knee designs were examined using a standard testing protocol developed by Harris et al. [J Biomech 32:951-958 (1999)] to investigate the polyethylene insert contact areas and pressures. A load of 3600 N was applied for 10 s at 0, 30, 60, 90, 110, 135 and 155 degrees of flexion. Contact areas and pressures at the femoral-polyethylene insert interface were measured with a I-scan 4000 system. Up to 110 degrees of flexion, the VANGUARD RP HI-FLEX showed the highest contact area and lowest pressure. At the deep flexion angles, contact area decreased and contact pressure increased significantly in all knees. The NexGen series showed a constant contact area throughout the various flexion angles. In general, all high flexion knees could result in almost point contact in an extremely high range of motion.
使用Harris等人[《生物力学杂志》32:951 - 958(1999)]制定的标准测试方案，对六种高屈曲膝关节设计的胫股关节界面进行了检查，以研究聚乙烯垫片的接触面积和压力。在0、30、60、90、110、135和155度屈曲时，施加3600 N的载荷持续10秒。使用I-scan 4000系统测量股骨 - 聚乙烯垫片界面的接触面积和压力。在高达110度的屈曲范围内，VANGUARD RP HI-FLEX显示出最高的接触面积和最低的压力。在深度屈曲角度时，所有膝关节的接触面积均减小，接触压力显著增加。NexGen系列在各个屈曲角度下的接触面积保持恒定。总体而言，所有高屈曲膝关节在极高的运动范围内几乎都可能导致点接触。
