Contamination by metallic elements released from joint prostheses.

When a metallic implant is in contact with human tissues, the organism reacts and a corrosion process starts. Consequently, we might observe liberation of metallic debris and wear. Our purpose is to measure the contamination and the migration of these metallic elements in the surrounding tissues of the implant. Two types of samples have been studied. First type is sample taken on post-mortem tissues around prostheses to study contamination gradients. Second type is sample taken on pathologic joints on periprosthetic capsular tissues in surgical conditions. These allow estimating contamination degree. The experiments were made on a Van de Graaff accelerator located at CERI (Centre d'Etude et de Recherche par Irradiation, Orléans, France). We measure elemental concentrations resulting from the contamination of the surface of each sample. Results are analysed in function of the pathology and the type of implants. According to the pathology and the location of the sampling, these measurements show a very heterogeneous contamination by metallic elements under particles and/or ionic species which can migrate through soft tissues by various mechanisms.