Metal-on-metal hip arthroplasty : local tissue reactions and clinical outcome

Abstract

Hip replacements using a metal-on-metal (MoM) bearing surface were reintroduced with the promise of low wear rates and easy revision in case of the resurfacing design. Although initially mid-term results were promising, local adverse soft tissure reactions to metal debris were detected around the year 2008. We studied the prevalence of these adverse reactions, known as pseudotumors, and analysed how well these could be identified with Metal Artefact Reducing Sequence Magnetic Resonance Imaging (MARS-MRI). We also studied the natural development of these pseudotumors and evaluated if measuring pseudotumor size in a clinical setting waa accurate. Based on metal ion analysis, symptoms and MARS-MRI scanning of a large cohort of MoM hip resurfacing patients, we proposed a treatment flow chart for these patients.