Jungwirth-Weinberger Anna, Hanreich Carola, Kasparek Maximilian F, Renner Lisa, Waldstein Wenzel, Boettner Friedrich
Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA.
Kantonsspital Baden, Im Ergel 1, 5404, Baden, Switzerland.
Arch Orthop Trauma Surg. 2023 Mar;143(3):1217-1221. doi: 10.1007/s00402-021-04206-2. Epub 2021 Nov 1.
Increased cobalt (Co) and chromium (Cr) serum levels are one reason for revision surgery in metal on metal (MoM) total hip arthroplasty (THA) patients. Dual mobility liners are a simple revision option; however, they preserve the metal shell and stem and it is therefore not clear if metal ion levels will fully normalize after revision surgery.
Between April 2013 and December 2017 25 hips (24 patients) underwent revision from a MoM THA to an off-label dual mobility liner. Five patients were lost to follow-up and one patient refused leaving 18 patients (11 men, 7 female, average age 63.9 years) for pre- and postoperative metal ion level blood tests at a minimum follow-up of 2 years.
Fourteen patients were revised for osteolysis, two for elevated metal ion levels and two for fluid or cysts around the femoral or acetabular component. The average preoperative Co and Cr levels were 8.3 µg/l and 5.0 µg/l, respectively. At a minimum follow-up of 2 years (30-95 months), metal ions dropped to 0.8 µg/l. Harris Hip Score (HHS), Hip Osteoarthritis Outcome Score (HOOS), Visual Analog Scale (VAS) and the UCLA activity score improved non-significantly from pre- to postoperative. There was one postoperative complication in the study cohort. One patient with persisting pain required revision surgery to a standard acetabular component during the follow-up period.
The off-label use of a dual-mobility liner in the current study resulted in normalization of the metal ion levels suggesting that preserving the cobalt-chromium acetabular component has little impact on ion levels. In addition, dual mobility liners have a low complication and revision rate.
血清钴（Co）和铬（Cr）水平升高是金属对金属（MoM）全髋关节置换术（THA）患者进行翻修手术的原因之一。双动衬垫是一种简单的翻修选择；然而，它们保留了金属髋臼杯和股骨柄，因此翻修手术后金属离子水平是否会完全恢复正常尚不清楚。
2013年4月至2017年12月期间，25例髋关节（24例患者）从MoM THA翻修为使用非标签双动衬垫。5例患者失访，1例患者拒绝随访，剩余18例患者（11例男性，7例女性，平均年龄63.9岁）接受了至少2年的术前和术后金属离子水平血液检测。
14例患者因骨溶解进行翻修，2例因金属离子水平升高进行翻修，2例因股骨或髋臼部件周围出现积液或囊肿进行翻修。术前钴和铬的平均水平分别为8.3μg/L和5.0μg/L。在至少2年（30 - 95个月）的随访中，金属离子降至0.8μg/L。Harris髋关节评分（HHS）、髋关节骨关节炎结局评分（HOOS）、视觉模拟评分（VAS）和加州大学洛杉矶分校（UCLA）活动评分从术前到术后均有非显著性改善。研究队列中有1例术后并发症。1例持续疼痛的患者在随访期间需要翻修至标准髋臼部件。
本研究中使用非标签双动衬垫使金属离子水平恢复正常，这表明保留钴铬合金髋臼部件对离子水平影响不大。此外，双动衬垫的并发症和翻修率较低。
