title: Metal hypersensitivity and metal ion levels in patients with coated or uncoated total knee arthroplasty: a randomised controlled study.
abstract: OBJECTIVE
  Metal ion release by orthopaedic implants may cause local and systemic effects and induce hypersensitivity reactions. Coated implants have been developed to prevent or reduce these effects. This study was initiated to investigate the safety of a novel coating for total knee arthroplasty (TKA) implants.
  
  
  METHODS
  A total of 120 patients undergoing primary TKA with no history of hypersensitivity and no other metal implant were randomised to receive either a coated or uncoated implant. Chromium (Cr), cobalt (Co), molybdenum (Mb) and nickel (Ni) hypersensitivity patch testing and plasma ion concentrations were evaluated pre-operatively and one year post-operatively.
  
  
  RESULTS
  At the one year follow-up both groups demonstrated significant improvement in knee function and quality of life. One new weakly positive reaction to Co in the TKA group with coated implant and two doubtful skin reactions to Ni (one in each group) were noted. Even with sensitisation to implant materials no skin reactions were observed. Plasma metal ion concentrations did not increase and were not elevated at the one year follow-up in either group.
  
  
  CONCLUSIONS
  Sensitisation after TKA was rare and had no influence on clinical results. TKA with coated implant and standard TKA demonstrated no plasma metal ion elevation.
authors.affiliation: Department of Orthopaedic Surgery, University Hospital Carl Gustav Carus, Medical Faculty of the Technical University of Dresden, Fetscherstr. 74, 01307, Dresden, Germany, Joerg.Luetzner@uniklinikum-dresden.de.
authors.forename: Jörg
authors.initials: J
authors.lastname: Lützner
authors.forename: Albrecht
authors.initials: A
authors.lastname: Hartmann
authors.forename: Gerd
authors.initials: G
authors.lastname: Dinnebier
authors.forename: Petra
authors.initials: P
authors.lastname: Spornraft-Ragaller
authors.forename: Christine
authors.initials: C
authors.lastname: Hamann
authors.forename: Stephan
authors.initials: S
authors.lastname: Kirschner
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000295:instrumentation*; D002857:Chromium / Q000009:adverse effects / Q000097:blood; D003035:Cobalt / Q000009:adverse effects / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006967:Hypersensitivity / Q000453:epidemiology* / Q000209:etiology*; D015994:Incidence; D007477:Ions / Q000097:blood*; D007720:Knee Prosthesis / Q000009:adverse effects*; D008297:Male; D008670:Metals / Q000009:adverse effects*; D008875:Middle Aged; D008982:Molybdenum / Q000009:adverse effects / Q000097:blood; D009532:Nickel / Q000009:adverse effects / Q000097:blood; D020370:Osteoarthritis, Knee / Q000601:surgery; D011474:Prosthesis Design / Q000145:classification*; D011788:Quality of Life; D016896:Treatment Outcome
chemical_list: D007477:Ions; D008670:Metals; D002857:Chromium; D003035:Cobalt; D009532:Nickel; D008982:Molybdenum