Predictivity and fate of metal ion release from metal-on-metal total hip prostheses.

Blood metal ion levels in 72 patients with large head metal-on-metal hip arthroplasty were studied to determine the correlation between the values measured in whole blood and urine. Urinary cobalt and chromium levels of 30μg and 21μg, respectively, adjusted to creatinine were found to correspond to the 7μg/l cut-off value that has been accepted in whole blood. Cobalt and chromium levels in whole blood and urine both significantly correlated with increased acetabular component inclination angle over 50 degrees and pain scores.

Serum ion levels after ceramic-on-ceramic and metal-on-metal total hip arthroplasty: 8-year minimum follow-up.

Alternative bearing surfaces for total hip arthroplasty, such as metal-on-metal and ceramic-on-ceramic, offer the potential to reduce mechanical wear and osteolysis. In the short and medium term, the second generation of metal-on-metal bearings demonstrated high systemic metal ion levels, whereas ceramic-on-ceramic bearings showed the lowest ones. We aimed to verify whether the long-term ion release in metal-on-metal subjects was still relevant at a median 10-year follow-up, and whether a fretting process at the modular junctions occurred in ceramic-on-ceramic patients and induced an ion dissemination.