Journal of Orthopaedic Reports (Dec 2023)
Early bilateral simultaneous atypical femur fracture after 18 months of Risedronate therapy: Case report and literature review
Abstract
Background: Atypical femur fractures (AFFs) are stress or insufficiency fractures often associated to long term use of bisphosphonates (BPs). AFFs are usually not comminuted, sometimes bilateral involving the subtrochanteric region or the diaphysis. Prodromal symptoms may have been present for weeks or months before AFFs. The aim of this case report is to highlight that the correlation between the duration of BPs therapy and the risk of AFFs may be not so strong as reported in the literature, and to evaluate the tools available to the physician for preventing this complication. Case report: A 54 years old woman was transported by ambulance to our emergency department following an accidental fall in the street. She experienced bilateral thigh collapse accelerating her step while crossing the street and was unable to get up complaining severe pain in both lower limbs. X-rays showed bilateral complete transverse fracture of the femoral diaphysis. Early treatment in emergency department has been application of trans-tibial traction; on the same day the patient was admitted to orthopaedic department. Investigating patient's medical history, it emerged that the only medication she had been taking was Risedronate, for only 18 months, for a diagnosis of osteoporosis 6 years earlier. As prodromal symptom, about 6 months before hospitalization, she started experiencing bilateral thigh pain, without investigating it. Subsequently she underwent fixation with anterograde long intramedullary nails. Both femurs were treated in the same operating session. From the day after surgery, she began passive mobilization and strengthening of postural muscles; on the fourth day after surgery she began the protocol of re-education to standing and walking with progressive load over time. Conclusion: This case report highlights the possible limitations of the current management of BPs therapy. The occurrence of AFFs may not be solely dependent on the duration of BPs therapy and the age of patients, as widely acknowledged in the current literature. The management of BPs therapy may require a redefinition, with the need, according to the authors, to evaluate the introduction of therapeutic windows, especially in patients with clinical signs of high risk of AFFs.
