Increased blood cobalt and chromium after total hip replacement.
OBJECTIVE
To determine metal concentrations in blood and urine of patients who received cobalt-chromium-alloy metal on metal hip implants.


METHODS
Cobalt and chromium were determined in blood and urine of 76 patients and 26 controls by electrothermal atomic absorption spectroscopy.


RESULTS
A significant postoperative elevation of the metal concentrations was observed for total hip replacement patients in contrast to the control group. Twenty-nine patients exceeded the EKA (Expositionäquivalente für Krebserzeugende Arbeitsstoffe) threshold limits for cobalt in blood and for cobalt and chromium in urine. We obtained a significant correlation between cobalt in blood and cobalt in urine (r = 0.79; p < 0.005), chromium in blood and chromium in urine (r = 0.79; p < 0.005), cobalt in blood and chromium in blood (r = 0.69; p = 0.008), and cobalt in urine and chromium in urine (r = 0.95; p = 0.004).


CONCLUSIONS
Our findings suggest that in total hip replacements using metal-metal pairings, metal ions of the alloys are released. This release may lead to significantly elevated metal concentrations in biological fluids. Long-term studies are needed to determine the risk of metal-metal implants as a potential cause of cobalt and chromium toxicity.
Schaffer
A W
AW
Department of Occupational Medicine, University of Vienna, Austria. Andreas.Schaffer@akh-wien.ac.at
Pilger
A
A
Engelhardt
C
C
Zweymueller
K
K
Ruediger
H W
HW
D000328:Adult; D019644:Arthroplasty, Replacement, Hip; D002857:Chromium / Q000097:blood* / Q000652:urine; D003035:Cobalt / Q000097:blood* / Q000652:urine; D005260:Female; D006801:Humans; D008297:Male; D011184:Postoperative Period; D013054:Spectrophotometry, Atomic
D002857:Chromium; D003035:Cobalt