Characteristic features and surgical outcome in bisphosphonate-associated atypical femoral fracture: A retrospective observational study

Background: Bisphosphonate-associated atypical femoral fracture (AFF) is a rare and serious condition with poorly understood characteristics and management. Objectives: This study aimed to evaluate the characteristic features and outcomes of AFF in a two-center cohort study. Methods: In this retrospective survey, the medical records of 22 AFF patients were reviewed, who have used alendronate for > 12 months. The demographic characteristics (e.g., age, gender, and body mass index), clinical features (e.g., symptoms and symptom duration), radiologic characteristics (e.g., fracture site, the severity of the fracture, and contralateral involvement), surgical characteristics (e.g., the type of surgery unio‎n period), and postoperative complications (e.g., fixation failure and unio‎n problems) were extracted from the patients’ profiles. Results: The study population included 4 males and 18 females with a mean age of 70.6±11.9 years. The mechanism of fracture was falling in 21 (95.5%) patients. The mean duration of bisphosphonate consumption was estimated at 3.8±2 years. Prodromal symptoms (pain and limping) were recorded in 12 (54.55%) patients. The fractures were in the femoral shaft and subtrochanteric in 15 (68.2%) and 7 (31.8%) patients, respectively. The fixation device was the intramedullary nail and plate in 18 (81.8%) and 4 (18.2%) patients, respectively. The mean unio‎n period was obtained at 8.3±2.8 months. unio‎n complications (delayed or nonunio‎n) occurred in 6 (27.3%) patients. It was reported that fixation failed in 5 (22.7%) patients, including 3 nails and 2 plate fixations. Conclusions: Based on the results, AFF was associated with a prolonged unio‎n. The intramedullary nail provided a more secure fixation. Prodromal symptoms could be used for earlier detection of patients.