Review Question - QID 212985

This patient has bisphosphonate-related changes of her femurs. Given that the left side is the only symptomatic side, it should be prophylactically nailed.

Bisphosphonates have been implicated in causing atypical low-energy femur fractures. Radiographic clues for this impending injury include lateral cortical thickening (beaking), varus remodeling of the femur, and increased diaphyseal cortical thickness. When a fracture occurs, it usually occurs in the subtrochanteric region. The fracture patterns are usually transverse or short-oblique in orientation. There is also a lack of comminution. The ideal treatment for these injuries is an intramedullary nail, ensuring to restore native alignment and avoiding varus.

Vasikaran performed a review of low-energy femoral fractures with prolonged bisphosphonate use. He reported that long-term bisphosphonate therapy is thought to lead to profound suppression of bone turnover, increased microdamage accumulation, and alteration of bone tissue mineral properties as well as possibly bone tissue composition by altering collagen cross-linking, all of which can in turn cause brittleness of bone and propensity to fracture with minimal trauma. He concludes that, if a patient becomes symptomatic or sustains a fracture, the cessation of bisphosphonate therapy should be considered. If a fracture has not occurred and the patient is having prodromal symptoms, prophylactic intramedullary nailing should be performed.

Balach et al. performed a review on atypical femur fractures associated with disphosphonate use. They report that following the diagnosis of a complete or impending atypical femur fracture, discontinuation of diphosphonates is recommended to help promote a more favorable fracture healing environment. They conclude that surgical treatment should allow endochondral fracture healing such as an intramedullary nail.

Figures A and B are AP radiographs of the left and right proximal femurs demonstrating lateral cortical beaking, cortical thickening, and mild varus remodeling.

Incorrect Answers:
Answer 1: Observation and pain control is not appropriate in this case as the patient has an impending fracture.
Answer 2: A bone scan is not necessary in this case as the diagnosis can be made from radiographs.
Answer 4: Intramedullary nailing of both sides is not necessary at this time as the right side is asymptomatic.
Answer 5: Referral to an orthopaedic oncologist is not necessary for treating these injuries.