Position Statement: Atypical Femoral Fracture from the Korean Society for Bone and Mineral Research in 2023

Abstract

As the aging population increases, the number of patients with osteoporosis is gradually rising. Osteoporosis is a metabolic bone disease characterized by low bone mass and the microarchitectural deterioration of bone tissue, resulting in reduced bone strength and an increased risk of low-energy or fragility fractures. Thus, the use of anti-resorptive agents, such as bisphosphonates (BPs), to prevent osteoporotic fractures is growing annually. BPs are effective in reducing hip and other fractures. However, the longer a patient takes BPs, the higher the risk of an atypical femoral fracture (AFF). The exact mechanism by which long-term BP use affects the development of AFFs has not yet been clarified. However, several theories have been suggested to explain the pathogenesis of AFFs, such as suppressed bone remodeling, impaired bone healing, altered bone quality, and femoral morphology. The management of AFFs requires both medical and surgical approaches. BPs therapy should be discontinued immediately, and calcium and vitamin D levels should be evaluated and supplemented if insufficient. Teriparatide can be used for AFFs. Intramedullary nailing is the primary treatment for complete AFFs, and prophylactic femoral nailing is recommended if signs of an impending fracture are detected.

Does the Nonunion Rate of Atypical Femoral Fractures Differ According to Fracture Site?: A Meta-Analysis

“…Atypical femoral fractures (AFF) are a rare but specific type of fracture that typically exhibits a short or transverse oblique orientation, occurs with minimal or no associated trauma, features a medial spike in complete fractures, and lacks comminution with high mortality when occurring in frail, elderly patients. 1) While intramedullary (IM) full-length nailing is a common treatment of choice for AFF, substantial concern persists regarding the potential for delayed or unsuccessful healing even after the stabilization of AFF. 2 3) …”