Characteristic features and surgical outcome in bisphosphonate-associated atypical femoral fracture: A retrospective observational study

Bisphosphonate-associated atypical femoral fracture (AFF) is a rare and serious ‎condition with poorly understood characteristics and management. ‎

To evaluate the characteristic features and outcomes of AFF in a two-center cohort ‎study.‎

In a retrospective survey, medical profiles of 22 AFF patients, who have used ‎alendronate for > 12 months, were reviewed. The demographic characteristics such as age, ‎gender, and BMI, the clinical features including symptoms, symptom duration, radiologic ‎characteristics including fracture site, the severity of the fracture, and contralateral involvement, ‎surgical characteristics including the type of surgery union period and postoperative ‎complications such as fixation failure, and union problems were extracted from the patients’ ‎profiles.‎

The study population included 4 males and 18 females with a mean age ‎of ‎70.6±11.9 ‎‏ ‏years. ‎‏The mechanism ‎of fracture was falling down‎ in 21 (95.5% ) patients. The ‎mean duration of ‎‏bisphosphonate consumption was ‎‏‎3.8±2 ‎‏‎ years. Prodromal symptoms (pain and ‎limping) were recorded in 12 (54.55%) ‎‏patients. ‎‏The fracture was in the femoral shaft in 15 ‎‎(68.2%) and in the subtrochanteric‎‏‎ in 7 (‎‏‏‎31.8%) patients. ‎‏The fixation device was ‎‏the ‎intramedullary nail in 18 (81.8%) and plate in 4 (18.2%) patients. ‎‏The mean union period was ‎‏‎8.3±2.8 ‎months. Union complications (delayed or ‎‏nonunion) occurred in 6 (27.3%) patients. ‎Fixation failed in 5 (22.7%) patients (3 nails and 2 ‎‏plate fixation).‎‏

AFF is associated with a prolonged union. ‎‏The intramedullary nail provides a more ‎secure fixation. Prodromal symptoms could be used for earlier detection of patients. ‎‏