Early Failure of a Modular Femoral Neck Total Hip Arthroplasty Component

Abstract

The PROFEMUR Z modular total hip arthroplasty component (Wright Medical Technology, Arlington, Tennessee) is a primary total hip replacement system that offers surgeons the ability to alter the length and version of the femoral neck after the femoral stem has been implanted. The modularity is achieved through taper interfaces at the distal and proximal ends of the femoral neck. The proximal femoral neck taper engages with the femoral head, and the distal taper engages with the femoral stem. In this report, we present the case of a patient who twice underwent total hip arthroplasty revision surgery. The first revision was due to a fractured ceramic femoral head. The second revision was due to a complete fracture of the modular femoral neck. This report will focus on the second revision, and, specifically, the failure of the modular femoral neck at the junction of the neck to the femoral stem. The patient was informed that data concerning the case would be submitted for publication, and he consented. A sixty-two-year-old man (height, 181 cm; weight, 84 kg; body mass index, 25.6 kg/m2) presented with severe primary osteoarthritis of the left hip. He underwent uneventful primary total hip replacement surgery in November 2006. The components implanted were a 58-mm Lineage cup fixed with two screws; a size-5 PROFEMUR Z modular stem with a modular, long, 8° retroverted neck; a 32-mm ceramic femoral head with a +3.5-mm offset; and a ceramic Transcend liner (Wright Medical Technology). The patient recovered well with no postoperative complications. In February 2007, the patient presented to the emergency department with a painful left hip. Radiographs revealed superior migration of the femoral head, and a fracture of the ceramic head was suspected. The patient was hospitalized, and revision total hip arthroplasty was performed. During the procedure, the head was found …