Predicting the Metal Ion Release From CoCrMo Alloy–UHMWPE Tribocorrosion Contacts

Due to tribocorrosion, metal ions are released from metallic components in hip implants and cause adverse reactions. The adverse reaction sensitivity to metal ions showed high dependency on individual patient and it has been recognized that adverse reactions even occur in patients with metal-on-polymer articulations. In this study, based on a tribocorrosion model for CoCrMo alloy, a lubricated wear accelerated corrosion model was developed for CoCrMo alloy–UHMWPE tribocorrosion contacts. The model was verified and calibrated using laboratory tribometer experimental results and was used to predict metal ion release from CoCrMo alloy heads in MoP hip joints. The results showed correspondence between model predicted wear accelerated corrosion and literature reported material loss of CoCrMo alloy heads in MoP hip joints tested using hip joint simulators. This model provides a tool to predict the level of metal ions released from MoP hip joints and has the potential to be used by medical doctors to evaluate the risk of adverse reactions for patients planned to receive a MoP hip implant.

Graphical abstract