title: Metal-on-metal hip prostheses: correlation between debris in the synovial fluid and levels of cobalt and chromium ions in the bloodstream.
abstract: OBJECTIVE
  Hip prostheses with metal-on-metal (MoM) coupling can release cobalt-chromium particles and ions. The aim of this work is to verify the correlation between particles in the synovial fluid and circulating ions.
  
  
  METHODS
  Forty patients were enrolled; particles from synovial fluid were analysed by SEM–EDX (Scanning Electron Microscopy-Energy Dispersion X-rays analysis) and levels of circulating Co and Cr were assayed by ICP-MS (inductively-coupled plasma mass spectrometry).
  
  
  RESULTS
  In 16 cases we did not find any particles in the synovial fluid and the Co level in whole blood was 0.05–4.42 ppb; in seven with few particles the blood level was 2.2–15.6 ppb; in six cases with several particles the level was 5.0–54.3 ppb; finally, in 11 cases we isolated not only Co-Cr particles, but also Cr particles with low or absent Co and in these patients the circulating level of Co was 23.8–109.6 ppb. Co in serumand Cr level both whole blood and serum have shown a similar trend to Co; the correlation between all these values and the corresponding particles is statistically significant in all cases.
  
  
  CONCLUSIONS
  Co and Cr both in serum and whole blood represents a systemic representation of the particle release at local level and can therefore be used to confirm a diagnosis and monitor the wear process of MoM articular prostheses.
authors.forename: Dalila
authors.initials: D
authors.lastname: De Pasquale
authors.forename: Susanna
authors.initials: S
authors.lastname: Stea
authors.forename: Stefano
authors.initials: S
authors.lastname: Squarzoni
authors.forename: Barbara
authors.initials: B
authors.lastname: Bordini
authors.forename: Marilina
authors.initials: M
authors.lastname: Amabile
authors.forename: Simona
authors.initials: S
authors.lastname: Catalani
authors.forename: Pietro
authors.initials: P
authors.lastname: Apostoli
authors.forename: Aldo
authors.initials: A
authors.lastname: Toni
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation; D002857:Chromium / Q000097:blood*; D003035:Cobalt / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006622:Hip Prosthesis; D006801:Humans; D007477:Ions / Q000097:blood; D008297:Male; D008670:Metals; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D011475:Prosthesis Failure; D012189:Retrospective Studies; D013052:Spectrometry, X-Ray Emission; D013582:Synovial Fluid
chemical_list: D007477:Ions; D008670:Metals; D002857:Chromium; D003035:Cobalt