Eberhardt Alan W, McKee R Travis, Cuckler John M, Peterson Donald W, Beck Preston R, Lemons Jack E
Department of Biomedical Engineering, University of Alabama at Birmingham, Hoehn 370, 1075 13th street S., Birmingham, AL 35294, USA.
Int J Biomater. 2009;2009:185456. doi: 10.1155/2009/185456. Epub 2009 Jul 1.
Metal transfer to femoral heads may result from impingement against the metallic acetabular shell following subluxation/dislocation, or when metallic debris enters the articulation zone. Such transfers roughen the head surface, increasing polyethylene wear in total hip replacements. Presently, we examined the surface roughness of retrieved femoral heads with metallic transfer. Profilometry revealed roughness averages in regions of metal transfer averaging 0.380 mum for CoCr and 0.294 mum for ZrO(2) which were one order of magnitude higher than those from non-implanted controls. Scanning electron microscopy (SEM) revealed adherent transfers on these retrievals, with titanium presence confirmed by electron dispersive spectroscopy. Due to the concern for increased wear, metal transfer was induced on non-implanted heads, which were then articulated against flat polyethylene discs in multidirectional sliding wear tests. Increased polyethylene wear was associated with these specimens as compared to unaltered controls. SEM imaging provided visual evidence that the transfers remained adherent following the wear tests. Pre- and post-test roughness averages exceeded 1 mum for both the CoCr and ZrO(2) heads. Overall, these results suggest that metal transfer increases the surface roughness of CoCr and ZrO(2) femoral heads and that the transfers may remain adherent following articulation against polyethylene, leading to increased polyethylene wear.
金属转移至股骨头可能是由于半脱位/脱位后金属髋臼杯受到撞击，或者金属碎屑进入关节区域所致。这种转移会使股骨头表面变得粗糙，增加全髋关节置换术中聚乙烯的磨损。目前，我们检查了有金属转移的回收股骨头的表面粗糙度。轮廓测定法显示，钴铬合金金属转移区域的平均粗糙度为0.380微米，氧化锆为0.294微米，比未植入对照的粗糙度高一个数量级。扫描电子显微镜（SEM）显示这些回收物上有附着的转移物，电子能谱证实存在钛。由于担心磨损增加，在未植入的骨头上诱导产生金属转移，然后在多向滑动磨损试验中使其与扁平聚乙烯盘进行关节运动。与未改变的对照相比，这些标本的聚乙烯磨损增加。SEM成像提供了视觉证据，表明磨损试验后转移物仍然附着。钴铬合金和氧化锆股骨头试验前后的平均粗糙度均超过1微米。总体而言，这些结果表明金属转移会增加钴铬合金和氧化锆股骨头的表面粗糙度，并且转移物在与聚乙烯关节运动后可能仍然附着，从而导致聚乙烯磨损增加。
