Discontinuation of alendronate and administration of bone-forming agents after surgical nailing may promote union of atypical femoral fractures in patients on long-term alendronate therapy

BACKGROUND: Long-term alendronate therapy may lead to atypical femoral fractures in a very few patients. However, the management protocol to optimize fracture healing remains undetermined. The purpose of this study was to describe the time to union of atypical femoral fractures after surgical nailing in patients on long-term alendronate therapy, with continuation of alendronate or discontinuation of alendronate, and administration of bone-forming agents. FINDINGS: From January 2004 to December 2011, the records of patients at our institution on long-term alendronate therapy for more than 36 months and sustaining atypical femoral fractures that had undergone surgical nailing, with continuation of alendronate or discontinuation of alendronate and administration of bone-forming agents were reviewed. During the 8-year study period, we treated 10 atypical femoral fractures with surgical nailing in 7 consecutive osteopenic or osteoporotic patients on long-term alendronate therapy for more than 36 months. There were no post-operative complications or needs for revision surgery. All fractures achieved union during follow-up. Mean union time was 23.5 months (range, 18–31 months) for 6 fractures with continuation of alendronate after surgery, and 4.5 months (range, 4–5 months) for 4 fractures with discontinuation of alendronate and administration of bone-forming agents after surgery. CONCLUSIONS: Discontinuation of alendronate and administration of bone-forming agents after surgical nailing may promote union of atypical femoral fractures in patients on long-term alendronate therapy.