Implant Fracture of the Emperion Modular Femoral Stem at the Stem-Sleeve Interface

Abstract

Introduction : Modular femoral implants have gained increased popularity and widespread use in both primary and revision procedures. While the modular design allows surgeons greater flexibility, the addition of another mechanical interface poses the possibility of mechanical wear and failure. Implant fracture has been described in other modular implants, however fracture of the Emperion modular femoral stem is poorly represented in the literature. Case Description : Here we describe the case of a 66-year-old male who underwent a primary total hip arthroplasty with the Emperion modular femoral stem. Approximately twenty-five months after his initial procedure, the patient presented with an atraumatic fracture of the femoral component at the stem-sleeve interface. He subsequently underwent a revision total hip arthroplasty including an extended trochanteric osteotomy. Conclusions : Modular total hip systems are a good option in cases where achieving stable implant fixation, version, offset and leg length is challenging. However, there are multiple reports of early catastrophic failure due to cyclical stress at the modular interface coupled with mechanical corrosion. Given the possibility of early failure, patients with modular components should undergo close observation beyond the typical perioperative period.