Bilateral atypical femur fractures without bisphosphonate exposure

Abstract

Atypical femur fractures have common radiographic features that set them apart from more typical higher-energy subtrochanteric femur fractures. They are noncomminuted, transverse fractures with medial spiking of the femoral cortex and increased lateral cortical thickness. These fractures have been associated in the literature with the use of bisphosphonate medications. This case describes bilateral atypical femur fractures in a patient with a medical history devoid of bisphosphonate use. We present his history, co-morbidities, and subsequent treatment. From this case, we call attention to bisphosphonate use as not the only cause of subtrochanteric femur fractures with atypical features and highlight that some patients may sustain these injuries even bilaterally without use of the medications. In addition, it is important to identify this fracture type and obtain imaging of the contralateral femur to facilitate prophylactic treatment if needed.

Genetic Risk Factors for Atypical Femoral Fractures (AFFs): A Systematic Review

“…The potential importance of genetic factors is supported by the occurrence of AFFs in bisphosphonate‐naïve individuals . Some of these bisphosphonate‐naïve individuals were found to have an underlying monogenetic bone disease, such as hypophosphatasia, pycnodysostosis, osteopetrosis, X‐linked hypophosphatemia (XLH), and osteoporosis pseudoglioma syndrome (OPPG), leading to the hypothesis that carriers of pathogenic mutations (very rare variants) or polymorphisms (common variants) in genes related to these monogenetic bone diseases may predispose to AFFs.…”

Clinical Features and Outcomes of Bilateral Atypical Femoral Fractures

“…AFFs are primarily associated with prolonged use of BPs but have also been reported in patients who do not use BP [7]. Also, patients who receive denosumab for osteoporosis and metastatic bone disease are susceptible to AFFs [8,9].…”

Bilateral Atypical Femur Fracture after Prolonged Use of Alendronate - A Case Report

“…As possible measures to prevent atypical femoral fractures in patients treated with bisphosphonates, we recommend orientation regarding treatment adherence, periodical medical consultations and limiting the use of bisphosphonates to a maximum of 5 years [16]. Once the fracture is stabilised, we suggest discontinuation of treatment and proper fixation of the fracture.…”

“…When analysed in the context of all femoral shaft fractures, atypical fractures may be responsible for up to 50% of them [7], depending on the population studied. Bilateral commitment is described in up to 30% of these patients, especially with a treatment period longer than 3 years [12,16]. Moreover, shaft fractures are more frequent than subtrochanteric fractures in patients older than 50 years [6,12,14].…”