SUMMARY
In recent years, bisphosphonates and RANK-ligand inhibitors have become the mainstay of treatment for multiple types of osteoporosis, as well as several other metabolic bone diseases. Although rare, atypical femoral fracture is a recent but clearly defined complication of antiresorptive therapy with bisphosphonates, and likely also with denosumab. In this article, we present 3 different cases of atypical femoral fracture: an incomplete fracture linked to a bisphosphonate, an incomplete fracture linked to denosumab, and a complete atypical femoral fracture. Specific diagnostic steps and therapy are described. We also offer a complete overview of available literature concerning diagnosis, epidemiology, pathogenesis, treatment and future outlooks concerning this entity. Although antiresorptive therapy offers a very significant benefit in the prevention of osteoporotic fractures, clinicians should be aware of the possible complications, especially with long-term therapy.