Metal Ion Levels After Metal-on-Metal Total Hip Arthroplasty: A Five-Year, Prospective Randomized Trial

This report has been verified by one or more authors of the original publication.

105 patients with unilateral noninflammatory degenerative joint disease were randomized to undergo total hip arthroplasty using either a 28mm metal-on-metal bearing surface, a 36mm metal-on-metal bearing surface, or a 28mm metal-on-polyethylene bearing surface. The purpose of this study was to compare metal ion levels and clinical outcomes between the three treatment groups. Upon analysis, the metal-on-polyethylene group demonstrated significantly lower metal ion levels in serum and whole blood compared to both of the metal-on-metal groups, while increasing metal ion levels over time and higher erythrocyte cobalt levels were observed in the 36mm metal-on-metal group. Mean HHS scores, WOMAC scores, and SF-12 mental and physical scores were similar between all three treatment groups.