Ho JH, et al. - This study was performed to investigate whether there was a relationship between higher cobalt and chromium concentrations and systemic toxicity. The authors diagnosed 2 (6.5%) of 31 individuals referred for assessment of metal-on-metal hip joint prostheses (MoM-HP) with systemic cobalt toxicity. However, neither symptoms nor investigation results correlated with serum cobalt or chromium concentrations despite a high prevalence of reported symptoms.