Six-year results of a prospective study of metal ion levels in young patients with metal-on-metal hip resurfacings

J Bone Joint Surg Br. 2009 Feb;91(2):176-9. doi: 10.1302/0301-620X.91B2.21654.


We describe the findings at six years in an ongoing prospective clinicoradiological and metal ion study in a cohort of 26 consecutive male patients with unilateral Birmingham Hip Resurfacing arthroplasties with one of two femoral head sizes (50 mm and 54 mm). Their mean age was 52.9 years (29 to 67). We have previously shown an early increase in the 24-hour urinary excretion of metal ions, reaching a peak at six months (cobalt) and one year (chromium) after operation. Subsequently there is a decreasing trend in excretion of both cobalt and chromium. The levels of cobalt and chromium in whole blood also show a significant increase at one year, followed by a decreasing trend until the sixth year.

MeSH terms

  • Adult
  • Aged
  • Arthroplasty, Replacement, Hip*
  • Chromium / analysis*
  • Chromium / blood
  • Chromium / urine
  • Cobalt / analysis*
  • Cobalt / blood
  • Cobalt / metabolism*
  • Cobalt / urine
  • Epidemiologic Methods
  • Femur Head*
  • Hip Prosthesis / adverse effects*
  • Humans
  • Male
  • Middle Aged
  • Prosthesis Design
  • Time Factors
  • Treatment Outcome


  • Chromium
  • Cobalt