Atypical femur fractures: 81 individual personal histories

An online voluntary association of individuals who had incurred one or more atypical femur fractures (AFFs) while taking bisphosphonates for prevention or treatment of osteoporosis provided an opportunity to collect long-term histories.

Individuals from a nationwide general community completed an anonymous survey documenting their history.

Within a larger cadre, cases were selected where the documentation, including fracture radiographs, verified the diagnosis based on published standards. Eighty-one of this group responded to the anonymous survey.

We describe passively collected observational data only.

The incidence of a large number of potential variations was determined.

The mean duration of bisphosphonate treatment was 9.5 yr. Prevention was the initial indication in 68% of the subjects; 94% started on alendronate, 77% reported prodromal pain, only 16% of these were diagnosed with incident stress fractures, and 39.5% experienced a contralateral AFF from less than 1 month to 49 months after the first. Of 71 subjects with a completed first AFF, 38% reported delayed healing, 11% had a complete contralateral AFF, and 22% underwent prophylactic rodding for a contralateral stress AFF. Forty-four percent of subjects with complete AFFs were continued on a bisphosphonate after the fracture. Thirty-five percent incurred a metatarsal fracture.

AFF patients experienced delayed healing, prodromal pain, and persisting risk of a contralateral and/or other fracture. Femur pain evaluation in patients on long-term bisphosphonates may facilitate early diagnosis of stress AFFs, permitting intervention, thus reducing completed and/or contralateral or other fracture risk. The details of these histories will assist in counseling regarding prognosis after an initial AFF.