Chromium and cobalt ion release following
the Durom high carbon content, forged metal-on-metal surface
replacement of the hip 2007
P.-A. Vendittoli, MD, MSc, FRCS,
Associated Professor of Surgery1; S. Mottard, MD,
Orthopaedic Registrar2; A. G. Roy, MD, FRCS,
Associated Professor of Surgery1; C. Dupont, MSc,
Statistician2; and M. Lavigne, MD, FRCS,
Associated Professor of Surgery1
2 Maisonneuvé-Rosemont Hospital, Montreal
University, 5415 Boulevard de l’Assomption, Montréal, Québec
HIT 4B3, Canada.
We evaluated the concentrations
of chromium and cobalt ions in blood after
metal-on-metal surface replacement arthroplasty
using a wrought-forged, high carbon content chromium-cobalt
alloy implant in 64 patients. At one year, mean whole
blood ion levels were 1.61 µg/L (0.4 to 5.5) for
chromium and 0.67 µg/L (0.23 to 2.09) for cobalt.
The pre-operative ion levels, component size,
female gender and the inclination of the
acetabular component were inversely proportional to the
values of chromium and/or cobalt ions at one year
postoperatively. Other factors, such as age and
level of activity, did not correlate with the
levels of metal ions. We found that the levels of the
ions in the serum were 1.39 and 1.37 times higher for
chromium and cobalt respectively than those in
the whole blood.
The levels of metal ions obtained may be
specific to the hip resurfacing implant and
reflect its manufacturing process.