Atypical Femoral Fractures-Ongoing and History of Bone-Specific Therapy, Concomitant Diseases, Medications, and Survival.

Although atypical femoral fractures (AFFs) are generally rare events; several studies have indicated a potential link between AFF and long-term bone-specific therapies (BSTs). The aim of this study was to analyze the frequency of AFF and potential associations with prior or ongoing BST. A total of 8851 Caucasian female and male patients with de novo hip fractures treated in the largest Austrian level 1 trauma center from 2000 to 2013 were selected. Of the total, 194 patients with a de novo low-traumatic subtrochanteric or shaft fractures were identified: 35 atypical and 159 typical fractures. Of these patients, concomitant diseases, medication, previous fractures, and survival data were retrieved and analyzed. Female patients in both groups were significantly older. The median survival was significantly shorter in patients with AFF (9 vs 18 months; p < 0.0001). Cardiovascular disease, sarcopenia, chronic kidney disease, type 2 diabetes, smoking (past or current history), and prevalent fragility fractures were more frequent in AFF patients, as well as the concomitant use of phenprocoumon, furosemide, and sulfonylurea. Although the number of patients with current BST was less in (14.5%) both groups, more patients in the AFF group were previously treated with BST (71% vs 49%; p = 0.016), and they received these therapies for a longer time period. A combination of severe comorbidities, long-term pharmaceutical therapies, and a history of previous or ongoing BST was associated with an increased individual risk for AFF.