Sister chromatid exchange in patients with joint prostheses

The evaluation of sister chromatid exchanges (SCE) is used to establish the cytogenic damage in subjects exposed to toxic substances. The test is cons idered to be of the most sensitive and accurate indicators of damage and re sponds to toxic chemicals at low doses. We evaluated the incidence of SCE i n peripheral lymphocytes of patients with articular prostheses. Subjects wi th prostheses made of titanium-aluminium-vanadium alloys presented a signif icantly higher SCE number than the control population (6.3 +/- 2.3 vs 4.4 /- 1.3; P = .0128), whereas subjects with prostheses made of chrome-cobalt alloy or mixed prostheses presented a higher SCE value than the controls bu t not significantly different. The presence of high-frequency cells was ala rming only in 5 patients, 4 of whom had titanium alloy prostheses, whereas none belonged to the control group. The number of SCE was not affected by t he presence csf bone-cement used in prosthesis fixation or by the implant d uration. The indication of possible cytogenic damage in patients with titan ium alloy prostheses that emerged from this study should be considered care fully, even though the sample population was small.