title: Prevalence of Failure due to Adverse Reaction to Metal Debris in Modern, Medium and Large Diameter Metal-on-Metal Hip Replacements--The Effect of Novel Screening Methods: Systematic Review and Metaregression Analysis.
abstract: Metal-on-metal (MoM) hip replacements were used for almost a decade before adverse reactions to metal debris (ARMD) were found to be a true clinical problem. Currently, there is a paucity of evidence regarding the usefulness of systematic screening for ARMD. We implemented a systematic review and meta-analysis to establish the prevalence of revision confirmed ARMD stratified by the use of different screening protocols in patients with MoM hip replacements. Five levels of screening were identified: no screening (level 0), targeted blood metal ion measurement and/or cross-sectional imaging (level 1), metal ion measurement without imaging (level 2), metal ion measurement with targeted imaging (level 3) and comprehensive screening (both metal ions and imaging for all; level 4). 122 studies meeting our eligibility criteria were included in analysis. These studies included 144 study arms: 100 study arms with hip resurfacings, 33 study arms with large-diameter MoM total hip replacements (THR), and 11 study arms with medium-diameter MoM THRs. For hip resurfacing, the lowest prevalence of ARMD was seen with level 0 screening (pooled prevalence 0.13%) and the highest with level 4 screening (pooled prevalace 9.49%). Pooled prevalence of ARMD with level 0 screening was 0.29% and with level 4 screening 21.3% in the large-diameter MoM THR group. In metaregression analysis of hip resurfacings, level 4 screening was superior with regard to prevalence of ARMD when compared with other levels. In the large diameter THR group level 4 screening was superior to screening 0,2 and 3. These outcomes were irrespective of follow-up time or study publication year. With hip resurfacings, routine cross-sectional imaging regardless of clinical findings is advisable. It is clear, however, that targeted metal ion measurement and/or imaging is not sufficient in the screening for ARMD in any implant concepts. However, economic aspects should be weighed when choosing the preferred screening level.
authors.affiliation: Coxa Hospital for Joint Replacement, Biokatu 6b, 33900 Tampere, Finland.
authors.forename: Aleksi
authors.initials: A
authors.lastname: Reito
authors.affiliation: Coxa Hospital for Joint Replacement, Biokatu 6b, 33900 Tampere, Finland.
authors.forename: Olli
authors.initials: O
authors.lastname: Lainiala
authors.affiliation: Coxa Hospital for Joint Replacement, Biokatu 6b, 33900 Tampere, Finland.
authors.forename: Petra
authors.initials: P
authors.lastname: Elo
authors.affiliation: Coxa Hospital for Joint Replacement, Biokatu 6b, 33900 Tampere, Finland.
authors.forename: Antti
authors.initials: A
authors.lastname: Eskelinen
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000706:statistics & numerical data; D006801:Humans; D061825:Metal-on-Metal Joint Prostheses; D015995:Prevalence; D011475:Prosthesis Failure; D012044:Regression Analysis; D012189:Retrospective Studies