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Fracture of a dual-modular femoral component at the stem-sleeve junction in a metal-on-metal total hip arthroplasty.

Innovations in the design of dual-modular femoral components have afforded surgeons several intraoperative advantages during both primary and revision total hip arthroplasty (THA). Although use of these implants has become more popular, the long-term outcomes and potential complications of introducing a second modular junction are still to be determined. In addition, concerns about corrosion potentiation at modular junctions in metal-on-metal (MOM) THA have arisen in recent studies. In this article, we present a unique case of fracture at the modular junction of the stem and modular sleeve of a dual-modular femoral component implanted with a MOM articulation. The proposed mechanisms of failure, including crevice and fretting corrosion as well as the potential effect of metal debris generated by MOM articulations, are reviewed. This case report is the first to describe component fracture at the stem-sleeve junction of this modern-generation dual-modular femoral component. Surgeons who encounter a painful dual-modular femoral stem must entertain this mode of failure and consider junctional failure as a potential diagnosis for such a patient, particularly in the setting of a MOM articulation.