Atypical femoral fractures related to bisphosphonate therapy
A 75-year-old woman presented with pain in her left hip for three weeks. She had a history of previous fixation of an intertrochanteric fracture of the left femur with a dynamic hip screw (DHS) seven years ago. She was on BP (risedronate) for 51/2 years. A plain radiograph of the left hip was interpreted as normal []. In view of her symptoms and previous DHS fixation, a nuclear bone scan was performed. This revealed increased uptake in the lateral cortex of the upper femoral shaft, below the level of the trochanters, consistent with an insufficiency fracture []. Due to the presence of the DHS screw, her upper femur was considered to be protected against a stress fracture. She was managed conservatively with limitation of weight bearing. Her symptoms improved over a period of two months, and she continues to be asymptomatic in this region after one year of follow up.