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Trephine Use During Revision Total Hip Arthroplasty Resulting in Diaphyseal Osteonecrosis and Stress Fracture: A Case Report

Case: A fifty-three-year-old woman presented with a fracture of an extensively porous-coated femoral component. Revision was performed with use of trephine reamers to remove the distal portion of the stem. Despite radiographs that showed an acceptable position of the revision stem, she experienced substantial thigh pain at four months postoperatively, which persisted at twelve months. A technetium-99m bone scan demonstrated a 5-cm photopenic region, suggestive of thermal osteonecrosis. Two months later, there was evidence of callus formation, which is consistent with a stress fracture. The fracture was treated with protected weight-bearing; it healed with nonoperative management and resolution of the pain. Conclusion: A diaphyseal stress fracture secondary to thermal osteonecrosis associated with trephine use developed after removal of a broken femoral component; it healed without surgical intervention.