Orthopedic Unit, Department of Health Sciences, University of Florence, Firenze, Italy.
J Arthroplasty. 2020 Jun;35(6S):S294-S298. doi: 10.1016/j.arth.2020.02.050. Epub 2020 Feb 28.
Modular dual-mobility (MDM) total hip arthroplasty (THA) is designed with a cobalt-chromium liner inserted into a titanium acetabular component. The purpose of this study is to investigate the potential risks for fretting corrosion at this junction, by measuring serum metal ions, after MDM acetabular revision.
Thirty-seven patients with well-functioning revision THAs participated in a cross-sectional study at mean 5.1 (2-10) years after surgery. All received a trabecular titanium MDM acetabular component. The serum levels of cobalt and chromium were measured using mass spectrometry.
The mean values of chromium and cobalt were 2.08 μg/L (95% confidence interval 0.9-3.2, range 0.02-11.8) and 1.99 μg/L (95% confidence interval 0.81-3.17, range 0.07-16.05), respectively. Eleven patients (29, 7%) had ion levels above the normal range, with 6 (16.2%) above 5 μg/L and 5 (13.5%) between 1 and 5 μg/L. A significant correlation was found between an elevated serum metal ion level and University of California Los Angeles score (P = .016).
We conclude that serum metal level elevation may occur secondary to metal debris resulting from corrosion of the index MDM THA. This potential risk should be included in the decision-making process when dealing with revision arthroplasty in young and active patients.
模块化双动（MDM）全髋关节置换术（THA）的设计采用钴铬衬垫插入钛髋臼部件。本研究旨在通过测量 MDM 髋臼翻修后血清金属离子来探讨该交界处发生微动腐蚀的潜在风险。
37 例功能良好的翻修 THA 患者在术后平均 5.1（2-10）年参加了一项横断面研究。所有患者均接受了多孔钛 MDM 髋臼组件。使用质谱法测量血清中钴和铬的水平。
铬和钴的平均值分别为 2.08μg/L（95%置信区间 0.9-3.2，范围 0.02-11.8）和 1.99μg/L（95%置信区间 0.81-3.17，范围 0.07-16.05）。11 名患者（29%）的离子水平高于正常范围，其中 6 名（16.2%）高于 5μg/L，5 名（13.5%）在 1-5μg/L 之间。血清金属离子水平升高与加利福尼亚大学洛杉矶评分（UCLA）呈显著相关（P=0.016）。
我们的结论是，血清金属离子水平升高可能继发于 MDM THR 腐蚀产生的金属碎屑。在处理年轻和活跃患者的翻修关节置换时，应将这种潜在风险纳入决策过程。
