Sister chromatid exchanges and ion release in patients wearing fracture fixation devices

Abstract

The quantification of sister chromatid exchange (SCE) during mitosis is a useful index for evaluating genotoxic effects in subjects occupationally or incidentally exposed to potentially toxic substances. The authors investigated the hypothesis that ions released by corrosion from prosthetic components of fracture fixation devices are associated with change in SCE incidence. In the present study, ten patients with implants were examined, and fifteen subjects with no implants were used as controls. SCE and high frequency cell (HFC) numbers were evaluated in circulating lymphocytes. In addition, nickel (Ni) and chromium (Cr) ion values in the serum were measured because, after iron, these metals are major components of stainless steel. A significant increase in SCE numbers was observed in patients compared to the control population (4.9 +/- 1.3 vs. 3.5 +/- 1.4). Ni concentration was 1.71 +/- 1.49 ng/mL in patients and 0.72 +/- 0.52 ng/mL in control subjects; Cr concentration was, respectively, 1.01 +/- 0.77 ng/mL and 0.19 +/- 0. 27 ng/mL. The increase of serum Cr and Ni was statistically significant. No correlation was found between the increased Cr concentrations and SCE number while Cr ion levels were found to be significantly correlated to HFC. An inverse correlation between Ni level and SCE numbers was observed. Our findings suggest that Cr release by stainless steel implants could have a genotoxic effect; thus it would be useful to carefully monitor implanted subjects with regard to serum ion dosage, SCE analysis, and HFC evaluation. In any case, it would be appropriate to remove the implant when fracture fixation is reached.

Do Ion Levels In Hip Resurfacing Differ From Metal-on-metal THA at Midterm?

“…International and national working groups are discussing the reference values to be set for hazardous occupational toxicants in body fluids and biologic tolerance values for occupational exposure [13,23,26]. Studies reporting local or systemic damage caused by metal ion elevation are scarce [12,30,37]. Some authors have suggested a possible sensitizing effect of Cr and Co ions, but without evidence of a correlation between ion concentrations and exposure [14,15].…”

Genotoxicity of fixation devices analyzed by the frequencies of sister chromatid exchange

“…This was consistent with the findings of other studies carried out in patients exposed to nickel and chromium ions through the systemic route or inhalation. [22][23][24][25] Torgersen et al [26] reported an increase in transformation of lymphocytes and allergic reactions due to nickel alloy in patients treated by IMF. Merritt and Brown [27] indicated that particularly the ions of chromium, cobalt and nickel released from a metal alloy through corrosion have toxic effects.…”

“…SCE is thought to take place in the replication point, and SCE analysis is a technique used to study the effect of many chemical mutagens. [19,20,[22][23][24] In this study, our main purpose was to investigate the genotoxicity of different metal alloys used for the fixation of jaw fractures through the analysis of SCE.…”

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

“…However, the toxicological relevance of chronic low-grade exposure to ions in MOM implants should not be disregarded, especially for younger patients with long-time implant duration. In fact, ion release has been suspected to increase the risk of DNA damage, [48][49][50] and a potential for adverse effects on the reproductive systems should be taken account.…”