Metallosis in cemented titanium alloy total knee arthroplasty without apparent metal-on-metal articulation

Background: Metallosis is an uncommon phenomenon observed in late failures of cemented total knee arthroplasty (TKA), and it is rarely seen in the absence of metal-on-metal articulation. Methods: We report the case of a TKA patient with cemented titanium-alloy components and a polyethylene patella that was revised for early loosening with intra-operative severe metallosis. Results: We found that loosening and severe metallosis were associated with methacrylate particle abrasion on titanium alloy surfaces. Conclusion: Serum titanium ion level measurement may be helpful in the workup of a painful TKA with titanium-alloy components in order to establish a diagnosis.