Background: Plates and other devices made by several alloys have been introduced to reach the stability of bone fractured fragments. Elements constituting alloys could be detected especially in organs, yet also in local tissues. Aim of the present study is the analysis of tissues surrounding IRF devices analyzing the morphology of released particles and studying the behavior of adjacent tissues to check metallic elements diffusion.
Methods: Biopsies were retrieved from 18 patients, aged 20 to 76 years. The patients received IRF by plates, screws and grids from 4 months to 9 years. They were divided into five groups according to the local phlogistic degree. Ordinary light microscopy, scanning electron microscopy and X-ray microprobe analysis (EDS system) was used to perform morphological investigations and identification of metal particles and elements.
Results: Metal particles or elements arising from plates, screws or grid may undergo tissular diffusion and cellular uptake. Not only Chromium, Iron or Aluminium but also Titanium may be easily released from devices and engulfed in tissues. In particular Titanium diffusion is evident in fibrous tissue surrounding IRF devices. Aluminium appears to be particularly accumulated in a persistent way in fibrous tissues and shows a characteristic embedding pattern in lamellar bone.
Conclusions: The degree of local phlogosis appears to be strictly correlated to metallosis. Chromium, Iron, Aluminium and also Titanium, even if at different degree, give rise to phlogistic effects. Metallosis and phlogosis can produce a cascade process in which they are both the cause and the effect at the same time. The abundant release of Titanium, which does not normally produce clinical phlogosis as i.e. Aluminium, should be worthy of further investigations on its cellular effects.