Is surgery necessary for femoral insufficiency fractures after long-term bisphosphonate therapy?

Abstract

Background: Prolonged use of bisphosphonates in patients with osteoporosis reportedly induces femoral insufficiency fractures. However, the natural course of these fractures and how to treat them remain unknown.

Questions/purposes: We determined the rates of fracture displacement and subsequent operations of undisplaced insufficiency fractures of the femur in patients treated with prolonged bisphosphonate therapy.

Patients and methods: We retrospectively collected and reviewed the clinical course of 11 patients (14 fractures) who had been diagnosed as having an insufficiency fracture of the femur after prolonged use (mean, 4.5 years; range, 3-10 years) of bisphosphonate. All patients were women with a mean age of 68 years (range, 57-82 years). The fracture site was subtrochanteric in six and femoral shaft in eight. The minimum followup was 12 months (mean, 27 months; range, 12-60 months).

Results: During the followup period, secondary displacement of the fracture occurred in five of the 14 fractures after a mean of 10 months (range, 1-19 months). Three fractures were treated with internal fixation using a compression hip screw and two with intramedullary nailing. Because five additional fractures were treated surgically owing to intractable pain, surgery was performed in 10 of 14 insufficiency fractures during the followup period. All 10 fractures healed during followup. The remaining four patients (four fractures) not undergoing any surgery had persistent pain.

Conclusions: Femoral insufficiency fractures after prolonged bisphosphonate therapy seldom healed spontaneously and most patients had surgery either for fracture displacement or persistent pain.

Fig. 1A–D

Patient 4 was a 67-year-old woman who had pain in her right thigh. (A) Her radiograph shows a transverse fracture line and thickening of the lateral cortex at the subtrochanteric area. (B) Her bone scan shows hot uptake at the subtrochanteric area. (C) She experienced a slip after 1 month of followup. Her radiograph shows a completely displaced fracture. She underwent internal fixation using a compression hip screw. (D) Twelve months postoperatively, her radiograph shows complete union of the fracture.

Fig. 2A–D

Patient 2 was a 64-year-old woman who had pain in her left thigh. (A) Her radiograph shows a transverse fracture line and thickening of the lateral cortex at the subtrochanteric area. (B) At 16 months followup, her radiograph shows progression of the fracture line at the subtrochanteric area. (C) She underwent internal fixation using an intramedullary nail as a result of intractable pain. (D) A radiograph obtained 6 months postoperatively shows complete union of the fracture.