Abstract
Bisphosphonates are widely used for the treatment of osteoporosis to prevent fractures. Although their safety and efficacy have been well documented, some recent reports have drawn attention to a possible correlation between long term bisphosphonate therapy and the occurrence of insufficiency fractures owing to prolonged bone turnover suppression. A 71-year-old woman presented to our emergency room with pain and deformity of the left thigh with low energy injury. Radiographs showed a left femur subtrochanteric fracture and a transverse sclerotic fracture line in the right femur subtrochanteric area with cortical thickening, which indicate insufficiency fractures. She had been treated with sodium alendronate 70 mg per week for 6 years and was suffering from prodromal symptoms in both thighs from 3 months ago. After surgery and intraoperative bone biopsy for a left subtrochanteric fracture, her osteoporosis medication was changed with a bone forming agent. We have analyzed the characteristics of insufficiency fractures related to long term bisphosphonate therapy. Physicians should keep in mind the possibility of insufficiency fracture in cases such as ours, especially with prodromal thigh pain.
References
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