Metal-on-metal hip prostheses: Correlation between debris in the synovial fluid and levels of cobalt and chromium ions in the bloodstream

Dalila De Pasquale, Susanna Stea, Stefano Squarzoni, Barbara Bordini, Marilina Amabile, Simona Catalani, Pietro Apostoli, Aldo Toni

Research output: Contribution to journalArticle


Purpose: 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 serum and 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. Conclusion: 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.

Original languageEnglish
Pages (from-to)469-475
Number of pages7
JournalInternational Orthopaedics
Issue number3
Publication statusPublished - 2014



  • Cobalt
  • Corrosion
  • Hip prosthesis
  • Metal-on-metal
  • Wear

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine
  • Medicine(all)

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