Weekly Teriparatide for Delayed Unions of Atypical Subtrochanteric Femur Fractures

The occurrence of atypical femur fractures (AFFs) in patients on prolonged bisphosphonate treatment has been gaining medical attention, but the use of pharmacotherapy for these fractures has not been explored in detail. The authors describe a case of AFFs successfully treated with once-weekly administration of 56.5 μg teriparatide (TPTD).

The patient was a 74-year-old female patient who had been taking alendronate for approximately 6 years and who suffered with a fall while walking. X-rays revealed a subtrochanteric right femur fracture. The contralateral femur showed cortical thickening and a transverse radiolucent fracture line. Based on these specific features, the patient was diagnosed with AFF. The patient underwent osteosynthesis with intramedullary nailing for the right fracture. Alendronate treatment was discontinued. Low-intensity pulsed ultrasonography therapy did not affect the healing of the fracture with delayed union, even after 3 months of application. Prophylactic osteosynthesis was performed for the subtrochanteric left femur. Bone tissue collected from the left fracture site during surgery showed severe suppression of bone turnover. Union of bilateral femurs was achieved after 3 months of a once-weekly administration of TPTD.

Once-weekly TPTD treatment is shown to be beneficial for improving the healing of AFFs showing delayed union.