Lack of radiographic loosening signs in a hip resurfacing that failed by stem fracture.

Fracture of the femoral stem is a rare manifestation of femoral component loosening in hip resurfacing. The patient had undergone successful hip resurfacing 3 years prior to presentation, presenting with complaints of groin pain, but without radiographic evidence of loosening. At 6 years post-operatively, the patient again presented with groin pain. Radiographs demonstrated a mid-stem fracture. Analysis of the retrieved implant and resected femoral head following conversion to total hip arthroplasty indicated that component failure and fracture appeared to be secondary to failed fixation and implant loosening not related to osteonecrosis or acute femoral neck fracture. The case report highlights the difficulty in diagnosing femoral component loosening in hip resurfacing in the absence of gross implant subsidence or stem radiolucency.