Accurately Assessing the Extent of Titanium Leaks from Implants

A highly sensitive method to determine the levels of titanium (Ti) in human blood will help quantify Ti concentrations in patients fitted with orthopedic implants.

Researchers at the University of Oviedo (Spain) collected blood samples from 40 healthy individuals and 37 patients with Ti implants - 15 with tibia implants, eight with femur implants, and 14 with humerus implants (eight internal and six external fixation implants). Using isotope dilution analysis and mass spectrometry (IDA-ICP-MS), the researchers then analyzed the blood samples with a double-focusing inductively coupled plasma mass spectrometer.

The results showed that control individuals had very low levels of Ti in the blood (mean 0.26 g/L), whereas Ti concentrations were significantly higher for all the patients with implants. The sensitivity of the method was such that the researchers were also able to show significant differences in Ti levels for different types of bone fixation devices; the more invasive implants shed more metallic debris into the blood than the external, superficial designs. The study also identified how the Ti from the implants is transported in the bloodstream and potentially distributed and accumulated. The study was published early online on July 22, 2011, in Analytical and Bioanalytical Chemistry.

“The simplicity of the methodology based on isotope dilution analysis and the accuracy and precision of the obtained results should encourage the use of the proposed strategy on a routine basis,” concluded lead author PhD student Yoana Nuevo-Ordonez, MSc, and colleagues of the department of physical and analytical chemistry.

Titanium implants are routinely used for treating bone fractures, as well as in dental work. Recent studies have shown that Ti-based implants both corrode and degrade, generating metallic debris with potentially harmful biological effects over time, including hepatic injury and renal lesions. To assess possible implications it is first essential to accurately measure the basal, normal levels of Ti in the bloodstream, as well as quantify how much higher the levels are in patients with implants.

Related Links:
University of Oviedo