Metal-on-Metal: Ion Levels as an Intervention Strategy

摘要

Due to the wear-related problems with large diameter metal-on-metal THA components, ion levels of cobalt and chromium in blood or serum are used to identify bearings with high-wear rates. Threshold levels for critical concentrations for these two alloys are published and quite frequently revised. Patients and doctors are confused, if measured values are close to thresholds. A new approach is presented by an international expert panel endorsed by EFFORT and several national organizations suggesting the use of a range instead of a specific value as threshold. This approach supports the philosophy that metal ion concentrations by themselves are not a diagnosis but one-important-piece in the assessment of a patient with a metal-on-metal hip articulation.