RT Journal
A1 Kim, Paul R.
A1 Beaulé, Paul E.
A1 Dunbar, Michael
A1 Lee, Joshua K.L.
A1 Birkett, Nicholas
A1 Turner, Michelle C.
A1 Yenugadhati, Nagarajkumar
A1 Armstrong, Vic
A1 Krewski, Daniel
T1 Cobalt and Chromium Levels in Blood and Urine Following Hip Resurfacing Arthroplasty with the Conserve Plus Implant
JF The Journal of Bone & Joint Surgery
JO The Journal of Bone & Joint Surgery
YR 2011
FD May 4
VO 93
IS Supplement_2
SP 107
OP 117
DO 10.2106/JBJS.J.01721
UL http://dx.doi.org/10.2106/JBJS.J.01721
AB Background: 
  The purpose of the present study was to determine cobalt and chromium ion levels in the blood and urine of patients in whom a modern-generation metal-on-metal hip resurfacing device had been implanted.Methods: 
  A total of ninety-seven patients with a Conserve Plus metal-on-metal hip resurfacing implant were followed prospectively for two years. Cobalt and chromium levels in erythrocytes, serum, and urine were measured preoperatively as well as three, six, twelve, and twenty-four months postoperatively.Results: 
  The median serum cobalt and chromium ion levels were 1.04 µg/L (range, 0.31 to 7.42 µg/L) and 2.00 µg/L (range, 0.28 to 10.49 µg/L), respectively, at one year after surgery and 1.08 µg/L (range, 0.44 to 7.13 µg/L) and 1.64 µg/L (range, 0.47 to 10.95 µg/L), respectively, at two years after surgery. The corresponding mean levels (and standard deviations) of serum cobalt and chromium were 1.68 ± 1.66 µg/L and 2.70 ± 2.22 µg/L, respectively, at one year after surgery and 1.79 ± 1.66 µg/L and 2.70 ± 2.37 µg/L, respectively, at two years after surgery.Conclusions: 
  These levels compare favorably with other published ion results for metal-on-metal hip resurfacing and replacement implants. No pseudotumors or other adverse soft-tissue reactions were encountered in our study population. Further research is needed to determine the clinical importance of increased cobalt and chromium ion levels in serum and urine following metal-on-metal hip resurfacing.Level of Evidence: 
  Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.