Surgery Department of Maisonneuve Rosemont Hospital, University of Montreal, Montreal, Quebec, Canada.
J Arthroplasty. 2011 Feb;26(2):282-8. doi: 10.1016/j.arth.2009.12.013. Epub 2010 Mar 4.
Preoperative and postoperative ion concentrations were measured in 29 metal-on-metal, large-diameter head total hip arthroplasty (LDH-THA) patients. Mean chromium, cobalt (Co), and titanium levels from LDH-THA were 1.3, 2.2, and 2.7 μg/L at 12 months. The open femoral head design showed significantly higher Co concentrations than the closed design (3.0 vs 1.8 μg/L, P = .037). Compared with previously published ion levels from a hip resurfacing system presenting the same bearing characteristics, Co levels were significantly higher in LDH-THA (2.2 vs 0.7 μg/L, P < .001). This study has demonstrated that the addition of a sleeve with modular junctions and an open femoral head design of LDH-THA causes more Co release than bearing surface wear (157% and 67%, respectively). Even if no pathologic metal ion threshold level has been determined, efforts should be made to minimize its release. We recommend modification or abandonment of the modular junction and femoral head open design for this specific LDH-THA system.
对 29 例金属对金属、大头股骨头全髋关节置换术（LDH-THA）患者进行了术前和术后离子浓度测量。在 12 个月时，来自 LDH-THA 的平均铬、钴（Co）和钛水平分别为 1.3、2.2 和 2.7μg/L。开放式股骨头设计的 Co 浓度明显高于闭式设计（3.0 对 1.8μg/L，P=0.037）。与具有相同轴承特性的髋关节表面置换系统之前发表的离子水平相比，LDH-THA 中的 Co 水平明显更高（2.2 对 0.7μg/L，P<0.001）。本研究表明，LDH-THA 中增加带模块连接的套筒和开放式股骨头设计会导致比轴承表面磨损更多的 Co 释放（分别为 157%和 67%）。即使尚未确定病理性金属离子阈值水平，也应努力尽量减少其释放。我们建议对该特定 LDH-THA 系统进行模块连接和股骨头开放式设计的修改或废弃。
