Zhou Zong-Ke, Li Ming G, Börlin Niclas, Wood David J, Nivbrant Bo
Perth Orthopaedic Institute, the University of Western Australia.
Clin Orthop Relat Res. 2006 Jul;448:39-45. doi: 10.1097/01.blo.0000223999.10389.c9.
Ceramic-on-ceramic hip replacements might stress the bone interface more than a metal-polyethylene because of material stiffness, microseparation, and sensitivity to impingement. To ascertain whether this potentially increased stress caused an increased cup migration we compared a ceramic-on-ceramic with a metal-on-polyethylene implant for cup migration. Sixty one patients (61 hips) undergoing THA for osteoarthritis were randomized to ceramic on ceramic (Ce/Ce) or cobalt-chromium on cross-linked polyethylene bearings (PE) in the same uncemented cup shell. Migration was followed with RSA. At 2 years we observed similar mean cup translations in the 3 directions (0.07-0.40 mm vs. 0.05-0.31 mm, Ce/Ce vs. PE), as well as similar rotations around the 3 axes (0.31-0.92 degrees vs. 0.57-1.40 degrees). WOMAC and SF-36 scores were also similar and no radiolucent lines or osteolysis found. The large migration seen in some cups in both implant groups will require close monitoring to ascertain the reasons. Mean proximal wear of the polyethylene liners measured 0.016 mm between 2 and 24 months. Our data suggest there is no increased cup migration in the ceramic-on-ceramic implant compared with the metal-on-polyethylene, and they seem an equally safe choice. However, the low wear measured with the more versatile and less expensive cross-linked polyethylene makes it a strong contender.
Therapeutic Level I. See the Guidelines for Authors for a complete description of levels of evidence.
由于材料硬度、微分离以及对撞击的敏感性，陶瓷对陶瓷髋关节置换可能比金属对聚乙烯置换对骨界面造成更大压力。为确定这种潜在增加的压力是否会导致髋臼移位增加，我们比较了陶瓷对陶瓷与金属对聚乙烯植入物的髋臼移位情况。61例因骨关节炎接受全髋关节置换术（THA）的患者（61髋）被随机分为在相同非骨水泥髋臼壳中使用陶瓷对陶瓷（Ce/Ce）或钴铬合金对交联聚乙烯衬垫（PE）的两组。通过放射学立体测量分析（RSA）追踪移位情况。2年时，我们观察到两组在三个方向上的平均髋臼平移相似（Ce/Ce组为0.07 - 0.40毫米，PE组为0.05 - 0.31毫米），以及围绕三个轴的旋转也相似（Ce/Ce组为0.31 - 0.92度，PE组为0.57 - 1.40度）。Western Ontario和McMaster大学骨关节炎指数（WOMAC）及简明健康状况调查量表（SF - 36）评分也相似，且未发现透光线或骨溶解。两个植入物组中一些髋臼出现的较大移位需要密切监测以确定原因。在2至24个月期间，聚乙烯衬垫的平均近端磨损为0.016毫米。我们的数据表明，与金属对聚乙烯植入物相比，陶瓷对陶瓷植入物的髋臼移位没有增加，它们似乎是同样安全的选择。然而，更通用且成本更低的交联聚乙烯测量出的低磨损使其成为有力的竞争者。
治疗性I级。有关证据水平的完整描述，请参阅作者指南。
