We report the first use of synchrotron xray spectroscopy to characterize and compare the chemical form and distribution of metals found in tissues surrounding patients with metal-on-metal hip replacements that failed with (Ultima hips) or without (current generation, large diameter hips) corrosion. The commonest clinical category of failure of metal-on-metal (MOM) hip replacements is “unexplained” and commonly involved a soft tissue inflammatory response. The mechanism of failure of the Ultima MOM total hip replacement includes severe corrosion of the metal stem and was severe enough to be removed from clinical use. Corrosion is not a feature that we have found in the currently used MOM bearings. To better understand the biological response to MOM wear debris we hypothesized that tissue from failed hips with implant corrosion contained a different type of metal species when compared to those without corrosion.Summary
Introduction