Successful treatment of atypical femoral fracture with autogenous bone grafting in a patient on denosumab for bone metastasis from breast cancer: A case report

Atypical femoral fractures (AFFs) occur with minor trauma and are believed to be a potential complication of the prolonged use of antiresorptive agents, such as bisphosphonate and denosumab, for the treatment of bone metastasis. In comparison with typical femoral fractures, AFFs have a higher incidence of complications, including implant failure and delayed union or nonunion. This report describes the case of a 42-year-old woman who developed denosumab-associated AFF after denosumab therapy for bone metastasis from breast cancer. Surgical treatment with IMN was performed after open anatomical reduction. To reduce the risk of delayed union and nonunion, the autogenous bone graft obtained from the iliac crest was conducted. The radiograph taken 5 weeks after surgery showed callus formation. Full weight bearing was allowed 3 months after surgery. Six months postoperatively, radiographs and computed tomography images demonstrated bone union. Twelve months after surgery, the patient was able to walk easily without pain. For cancer patients with bone metastasis whose life expectancy may be limited, a decline in physical activity can be fatal. Consequently, it is crucial to avoid a decrease in activities of daily living brought about by delayed union or nonunion. In this regard, autogenous bone grafting is a viable and effective technique for the treatment of AFFs in patients with bone metastases.