title: Systemic cobalt toxicity from total hip arthroplasties: review of a rare condition Part 2. measurement, risk factors, and step-wise approach to treatment.
abstract: As adverse events related to metal on metal hip arthroplasty have been better understood, there has been increased interest in toxicity related to the high circulating levels of cobalt ions. However, distinguishing true toxicity from benign elevations in cobalt levels can be challenging. The purpose of this review is to examine the use of cobalt alloys in total hip arthroplasty, to review the methods of measuring circulating cobalt levels, to define a level of cobalt which is considered pathological and to review the pathophysiology, risk factors and treatment of cobalt toxicity. To the best of our knowledge, there are 18 published cases where cobalt metal ion toxicity has been attributed to the use of cobalt-chromium alloys in hip arthroplasty. Of these cases, the great majority reported systemic toxic reactions at serum cobalt levels more than 100 μg/L. This review highlights some of the clinical features of cobalt toxicity, with the goal that early awareness may decrease the risk factors for the development of cobalt toxicity and/or reduce its severity.
  
  
  CONCLUSIONS
  Severe adverse events can arise from the release of cobalt from metal-on-metal arthroplasties, and as such, orthopaedic surgeons should not only be aware of the presenting problems, but also have the knowledge to treat appropriately.
authors.affiliation: University of Toronto, 100 College Street Room 302, Toronto, Ontario, M5G 1L5, Canada.
authors.forename: M G
authors.initials: MG
authors.lastname: Zywiel
authors.affiliation: Philadelphia College of Osteopathic Medicine, 4190 City Line Ave, Philadelphia, PA 19131, USA.
authors.forename: J J
authors.initials: JJ
authors.lastname: Cherian
authors.affiliation: Sinai Hospital of Baltimore, 2401 West Belvedere Avenue, Baltimore, MD 21215, USA.
authors.forename: S
authors.initials: S
authors.lastname: Banerjee
authors.affiliation: University of Toronto, 200 Elizabeth Street, Toronto, Ontario, M5G 2C4, Canada.
authors.forename: A C
authors.initials: AC
authors.lastname: Cheung
authors.affiliation: University of Toronto, 200 Elizabeth Street, Toronto, Ontario, M5G 2C4, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Wong
authors.affiliation: University of Toronto, 200 Elizabeth Street, Toronto, Ontario, M5G 2C4, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Butany
authors.affiliation: University of Toronto, 200 Elizabeth Street, Toronto, Ontario, M5G 2C4, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Gilbert
authors.affiliation: University of Toronto, 200 Elizabeth Street, Toronto, Ontario, M5G 2C4, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Overgaard
authors.affiliation: University of Toronto, 100 College Street Room 302, Toronto, Ontario, M5G 1L5, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Syed
authors.affiliation: Rush University, 1611 W. Harrison St., Suite 400, Chicago, IL, 60612, USA.
authors.forename: J J
authors.initials: JJ
authors.lastname: Jacobs
authors.affiliation: Sinai Hospital of Baltimore, 2401 West Belvedere Avenue, Baltimore, MD 21215, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Mont
mesh_terms: D000368:Aged; D000818:Animals; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D002614:Chelating Agents / Q000627:therapeutic use; D003035:Cobalt / Q000009:adverse effects* / Q000032:analysis; D004195:Disease Models, Animal; D005260:Female; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D007477:Ions / Q000009:adverse effects / Q000032:analysis; D007676:Kidney Failure, Chronic / Q000150:complications; D008134:Long-Term Care; D008297:Male; D044342:Malnutrition / Q000150:complications; D061825:Metal-on-Metal Joint Prostheses; D008875:Middle Aged; D011183:Postoperative Complications / Q000628:therapy; D011474:Prosthesis Design; D051381:Rats; D012307:Risk Factors
chemical_list: D002614:Chelating Agents; D007477:Ions; D003035:Cobalt
keywords: Hip; Metal-on-metal; cobalt; toxicity