Ion release in stable hip arthroplasties using metal-on-metal articulating surfaces: A comparison between short-and medium-term results

L. Savarino, D. Granchi, G. Ciapetti, E. Cenni, M. Greco, R. Rotini, C. A. Veronesi, N. Baldini, A. Giunti

Research output: Contribution to journalArticlepeer-review

Abstract

The use of metallic heads articulating with metallic cups could solve the problem of polyethylene (PE) wear in total hip replacement (THR) with metal-on-PE bearings. A conspicuous release of metal ions from new models of metal-on-metal bearings has been found in the short-term, but it is yet unclear whether the medium-term corrosion rate is high or, on the contrary, it becomes negligible, because of the continuous surface finishing. Our purpose was to compare the serum ion values (nanograms per milliliter) in 15 patients with metal-on-metal stable prosthesis (Group A), in the short-term (subgroup A 1; mean follow-up: 24 mo) and medium-term (subgroup A2; mean follow-up: 52 mo), in order to determine whether the ion release decreased with time of implant. Chromium (Cr), cobalt (Co), molybdenum (Mo) and aluminum (Al) were analyzed. Twenty-two presurgical patients were used for comparison (Group B). The reference range was obtained from a population of 27 healthy subjects (Group C). Co and Cr levels in the medium-term (subgroup A 2) were not decreased in comparison with the short-term values (subgroup A1) and were significantly higher (p <0.001) than presurgical and reference values. Otherwise, Mo and Al concentrations were not significantly increased in comparison with reference values. In conclusion, despite the apparent advantage of metal-on-metal coupling, especially in younger patient populations, there is a major concern about the extent and duration of the relevant "internal" exposure to Cr and Co ions. This exposure should be carefully monitored, in order to clarify the biologic effects of ion dissemination and, consequently, to identify risks concerning long-term toxicity of metals.

Original languageEnglish
Pages (from-to)450-456
Number of pages7
JournalJournal of Biomedical Materials Research - Part A
Volume66
Issue number3
Publication statusPublished - Sep 1 2003

Keywords

  • Bearing
  • Implant
  • Metal ions
  • Metal-on-metal
  • Toxicity

ASJC Scopus subject areas

  • Biomedical Engineering
  • Biomaterials

Fingerprint Dive into the research topics of 'Ion release in stable hip arthroplasties using metal-on-metal articulating surfaces: A comparison between short-and medium-term results'. Together they form a unique fingerprint.

Cite this