Malinzak Robert A, Small Scott R, Rogge Renee D, Archer Derek B, Oja Jordan W, Berend Michael E, Ritter Merrill A
Joint Replacement Surgeons of Indiana Foundation, Inc., Mooresville, Indiana.
Department of Applied Biology and Biomedical Engineering, Rose-Hulman Institute of Technology, Terre Haute, Indiana.
J Arthroplasty. 2014 Mar;29(3):541-7. doi: 10.1016/j.arth.2013.08.024. Epub 2013 Nov 27.
Limited experimental data exist comparing the mechanical response of the tibial cortex between fixed and rotating platform (RP) total knee arthroplasty (TKA), particularly in the revision setting. We asked if RP-TKA significantly affects tibiofemoral torque and cortical stain response in both the primary and revision settings. Fixed and RP tibial trays were implanted into analogue tibias and biomechanically tested under axial and torsional loading. Torque and strain response were analyzed using digital image correlation. Fixed bearing designs exhibited 13.8 times greater torque (P<0.01), and 69% (P<0.01) higher cortical strain than RP designs. Strain response was similar in the primary and revision cohorts. The decrease in torque transfer could act as a safeguard to reduce stress, micromotion and torsional fatigue in scenario of poor bone stock.
关于固定平台和旋转平台（RP）全膝关节置换术（TKA）中胫骨皮质的力学反应对比，现有的实验数据有限，尤其是在翻修情况下。我们研究了RP-TKA在初次和翻修手术中是否会显著影响胫股扭矩和皮质骨应变反应。将固定平台和RP胫骨托植入模拟胫骨，并在轴向和扭转载荷下进行生物力学测试。使用数字图像相关技术分析扭矩和应变反应。与RP设计相比，固定平台设计的扭矩大13.8倍（P<0.01），皮质骨应变高69%（P<0.01）。初次和翻修队列中的应变反应相似。在骨量不佳的情况下，扭矩传递的降低可作为一种保护措施，以减少应力、微动和扭转疲劳。
