Bone Abstracts

Introduction: Bisphosphonates remain first-line pharmacological therapy for osteoporosis due to their effectiveness in reducing vertebral and non-vertebral fractures.

Case Report: The patient had a significant medical background including insulin-dependent type 2 diabetes mellitus, hypertension, ischaemic heart disease, hypercholesterolaemia, chronic kidney disease, vitamin D deficiency, and osteoporosis. She presented following a left femoral fracture and underwent open reduction and intramedullary nailing of the left femur on 11 December 2025. Prior to this event, she had been receiving alendronic acid therapy for just over two years for osteoporosis management. In the two to three months preceding the fracture, she experienced intermittent groin pain. A pelvic radiograph undertaken during this period did not reveal significant pathology. Following surgical management, concern was raised regarding the possibility of an atypical femoral fracture related to prolonged bisphosphonate use. The orthogeriatric team arranged imaging of the contralateral femur, which demonstrated cortical beaking of the distal third of the right femur, suggestive of early bisphosphonate-related stress changes. After multidisciplinary discussion with orthopaedic colleagues, prophylactic fixation was recommended to prevent progression to a complete fracture. She subsequently underwent successful prophylactic intramedullary nailing of the right femur on 19 December 2025, within ten days of the first operation. Following bilateral femoral fixation, the patient was discharged to a rehabilitation facility to improve mobility and functional independence. She was also referred to a metabolic bone clinic for review of future osteoporosis treatment options.

Discussion: Atypical femoral fractures are uncommon but important complications associated with long-term bisphosphonate therapy. Although bisphosphonates are highly effective in reducing osteoporotic fractures, prolonged suppression of bone remodelling can result in accumulation of microdamage and reduced bone elasticity, predisposing patients to stress-related fractures. Current evidence supports screening of the contralateral femur when atypical fracture is suspected, as bilateral involvement is common. Early identification of stress changes can prevent catastrophic fracture through prophylactic fixation.

Conclusion: This case highlights the importance of recognising atypical femoral fractures in patients receiving bisphosphonate therapy, particularly in those presenting with prodromal thigh or groin pain. Early identification of contralateral femoral changes and multidisciplinary management allowed timely prophylactic intervention and rehabilitation planning.