Surface analysis of early retrieved polyethylene tibial inserts for both knees in total knee replacement

•By analysing the surface of an early retrieved implants, both inserts (6 and 8 months) exhibited numerous scratch marks oriented in various directions and pits.•Abrasive wear and oxidation induced wear were found as the main wear damage modes of an early-retrieved UHMWPE tibial inserts which undergoes revision surgery within 1 years of their index arthroplasty.•Our data demonstrated a strong association between the change of molecular weight and degradation mechanical properties with oxidation and surface wear damage mode for both inserts.