Corrosion-Related Failures in Modular Total Knee Arthroplasty: A Narrative Review of Rare Published Clinical Cases.

» Corrosion at modular junctions is a well-known cause of failure in primary and revision total hip arthroplasty, but it is underrecognized in modular total knee arthroplasty (TKA) despite the potential to cause clinically significant implant failure. » Although descriptions vary throughout case reports, mechanically assisted crevice corrosion (MACC) appears to be the underlying failure mechanism at these modular TKA junctions, as is seen in femoral component modularity in total hip arthroplasty (THA). » Adverse local tissue reactions (ALTR) and fatigue fractures can occur even in well-fixed TKA implants and can be difficult to detect clinically or radiographically. » The femoral component in constrained or rotating-hinge designs may be at higher risk for corrosion-related complications. » An appropriate index of suspicion, improved surveillance protocols, advanced imaging, and design innovations are needed to aid diagnosis, mitigate future failures, and guide revision strategies.