title: Cobalt to Chromium Ratio is Not a Key Marker for Adverse Local Tissue Reaction (ALTR) in Metal on Metal Hips.
abstract: The diagnosis of adverse local tissue reaction (ALTR) after metal-on-metal total hip arthroplasty (MoMTHA) presents a significant challenge. No single biomarker is specific for ALTR. The purpose of this study was to determine if the ratio of cobalt to chromium ions is useful for diagnosing ALTR in MoMTHA. In 89 bearing-related revision THAs, preoperative cobalt and chromium ion levels were compared to an intraoperative soft tissue damage grading scale. The average cobalt to chromium ratio was 2.96 (0-20). There was no correlation between the tissue scale and the cobalt to chromium ratio (R=0.095; P=0.41). Many variables affecting ion production/excretion mitigate the use of the ion ratio. The cobalt to chromium ratio is not a predictive biomarker for ALTR in MoMTHA.
authors.affiliation: OrthoCarolina Hip and Knee Center, Charlotte, North Carolina.
authors.forename: Thomas K
authors.initials: TK
authors.lastname: Fehring
authors.affiliation: OrthoCarolina Hip and Knee Center, Charlotte, North Carolina.
authors.forename: Joshua L
authors.initials: JL
authors.lastname: Carter
authors.affiliation: OrthoCarolina Hip and Knee Center, Charlotte, North Carolina.
authors.forename: Keith A
authors.initials: KA
authors.lastname: Fehring
authors.affiliation: OrthoCarolina Research Institute, Inc., Charlotte, North Carolina.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Odum
authors.affiliation: OrthoCarolina Hip and Knee Center, Charlotte, North Carolina.
authors.forename: William L
authors.initials: WL
authors.lastname: Griffin
mesh_terms: D000465:Algorithms; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000295:instrumentation*; D015415:Biomarkers / Q000378:metabolism; D002857:Chromium / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D006615:Hip / Q000601:surgery; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D007477:Ions; D008670:Metals; D009336:Necrosis; D011474:Prosthesis Design; D012086:Reoperation; D012189:Retrospective Studies; D012995:Solubility
chemical_list: D015415:Biomarkers; D007477:Ions; D008670:Metals; D002857:Chromium; D003035:Cobalt
keywords: adverse local tissue reaction; chromium; cobalt; ion levels; metal-on-metal; pseudotumor