Microscopic analysis of characteristic surface features of a set of retrieved total hip implants (922.13)

Introduction: Total Hip Arthroplasty (THA) is considered one of the most successful orthopaedic interventions used for joint replacement. The purpose of this study was to characterize the particular surface features common to retrieved THA implants, in order to point out principal characteristics that lead to their failure. Methods: A set of fourteen retrieved implants was studied, their designs varying from metal-on-polyethylene (MoP), ceramic-on-polyethylene (CoP) and metal-on-metal (MoM). All specimens were analyzed using digital microscopy (Keyence VHX2000). Particularly corroded and scratched areas were further analyzed under Scanning Electron Microscopy (SEM, JEOL 5600), and Energy Dispersive X-ray Spectrometer (EDS, JEOL 5600). Results: The surface analysis revealed certain patterns of features. The implants were divided in their components (cup, liner, head and stem), each of which was studied for common characteristics. Large amount of scratching was found throughout all of the heads and cups, fo...