Panagiotidou A, Meswania J, Osman K, Bolland B, Latham J, Skinner J, Haddad F S, Hart A, Blunn G
University College London, Gower Street, London WC1E 6BT, UK.
University College London Hospitals NHS Foundation Trust, 170 Tottenham Court Road, London W1T 7HA, UK.
Bone Joint J. 2015 Apr;97-B(4):463-72. doi: 10.1302/0301-620X.97B4.34800.
The aim of this study was to assess the effect of frictional torque and bending moment on fretting corrosion at the taper interface of a modular femoral component and to investigate whether different combinations of material also had an effect. The combinations we examined were 1) cobalt-chromium (CoCr) heads on CoCr stems 2) CoCr heads on titanium alloy (Ti) stems and 3) ceramic heads on CoCr stems. In test 1 increasing torque was imposed by offsetting the stem in the anteroposterior plane in increments of 0 mm, 4 mm, 6 mm and 8 mm when the torque generated was equivalent to 0 Nm, 9 Nm, 14 Nm and 18 Nm. In test 2 we investigated the effect of increasing the bending moment by offsetting the application of axial load from the midline in the mediolateral plane. Increments of offset equivalent to head + 0 mm, head + 7 mm and head + 14 mm were used. Significantly higher currents and amplitudes were seen with increasing torque for all combinations of material. However, Ti stems showed the highest corrosion currents. Increased bending moments associated with using larger offset heads produced more corrosion: Ti stems generally performed worse than CoCr stems. Using ceramic heads did not prevent corrosion, but reduced it significantly in all loading configurations.
本研究的目的是评估摩擦扭矩和弯矩对模块化股骨部件锥度界面微动腐蚀的影响，并研究不同材料组合是否也有影响。我们研究的组合有：1）钴铬（CoCr）柄上的CoCr头；2）钛合金（Ti）柄上的CoCr头；3）CoCr柄上的陶瓷头。在试验1中，当产生的扭矩分别相当于0 Nm、9 Nm、14 Nm和18 Nm时，通过在前后平面上以0 mm、4 mm、6 mm和8 mm的增量偏移柄来施加逐渐增加的扭矩。在试验2中，我们通过在内外侧平面上使轴向载荷的施加偏离中线来研究增加弯矩的影响。使用的偏移增量相当于头部 + 0 mm、头部 + 7 mm和头部 + 14 mm。对于所有材料组合，随着扭矩增加，电流和振幅显著更高。然而，Ti柄显示出最高的腐蚀电流。使用更大偏移头部导致的弯矩增加会产生更多腐蚀：Ti柄通常比CoCr柄表现更差。使用陶瓷头并不能防止腐蚀，但在所有加载配置下都能显著减少腐蚀。
