Bilateral Atypical Femoral Fractures Following Long- Term Bisphosphonate Therapy. A Case Report.

Introduction. Bisphosphonates are widely used for the treatment of osteoporosis. Decreased bone remodeling in time may cause a stress fracture in the femoral shaft. It is a rare occurrence for bisphosphonates therapy with an incidence rate of 3.2 to 5o cases per 100,000 person-years.
Case description. A79-year-old woman was admitted to the Hospital of Traumatology and Orthopaedics with diaphyseal fracture of the right femur without trauma. From August the patient began experiencing pain in the same area. Day after the injury, surgery was performed - right femur osteosynthesis with Expert intramedullary nailing and a biopsy to exclude oncological disease. Several years ago, the patient was diagnosed with osteoporosis and for the last eight years has been undergoing bisphosphonate therapy with ibandronic acid. Preoperative CT scan revealed transverse fracture and cortical thickening in right femur diaphysis, and incomplete unicortical stress fracture in left femur diaphysis. Five days later, a preventive Expert intramedullary nailing operation was performed on the left femur to reduce
the possibility of a complete fracture. The patient was mobilized on the first postoperative day. It was decided to change bisphosphonates to parathormone analog - Teriparatide. The patient was discharged ni satisfactory condition, moving with a walking frame, for further ambulatory treatment.
Summary. A patient with a history of osteoporosis underwent surgical treatment with intramedullary nailing for atypical femoral fracture in the right leg. Tominimize the likelihood
of a complete fracture, a preventive intramedullary nailing operation was performed on the left femur.
Conclusions. Patients undergoing bisphosphonate treatment for osteoporosis may experience atypical femoral fractures, even without trauma. The risk of femoral shaft fractures
escalates after long-term bisphosphonate therapy exceeding 5 years. To mitigate this risk, regular patient examinations are essential. Switching therapy to parathormone analogues and
surgical treatment may also be required.