[Urinary concentration of cobalt and chromium in patients with a non-cemented total hip prosthesis]

The concentrations of cobalt and chromium have been measured in the urine of 22 patients who had received uncemented hip prostheses made from cobalt, chromium and molybdenum alloy, and in 21 patients who had not received prostheses, using absorption spectrophotometry. The results were statistically analysed using the Wilcoxon test. The levels of cobalt in the urine in the patients with uncemented prostheses did not show a significant increase, indicating that there is no greater risk of cobalt toxicity. The concentration of chromium was significantly raised (p less than 10(-2) in the urine of patients with uncemented prostheses, and in three of these patients significant corrosion had occurred.