Fretting corrosion characteristics of polished collarless tapered stems in a simulated biological environment

The role fretting-corrosion plays on the degradation and formation of debris within the stem cement interface was investigated. Electrochemical measurements of potential and polarisation resistance, along with solution mass spectroscopy were employed. Optical, Scanning Electron and Transmission Electron Microscopy with Energy Dispersive X-Ray Spectroscopy techniques were utilised to observe surface morphology after fretting-corrosion tests. Electrochemical measurements indicated dynamic loading resulted in de-passivation of the metallic surface. Solution mass spectroscopy indicted high concentrations of cobalt were released from the interface, accounting for 94% of all metallic ions released into the environment. Detailed imagery of fretting-corrosion product indicated a chromium and oxygen layer on the metallic and bone cement surface owing to the electrochemical stability of species released as a result of fretting-corrosion.