Atypical femur fractures associated with bisphosphonate therapy: post-operative outcomes

• Published in: European journal of orthopaedic surgery & traumatology Vol. 33; no. 5; pp. 1697 - 1703
• Main Authors: Murphy, Benjamin, Francis, Sam L., Rhee, Isaac, Babazadeh, Sina, Stoney, James, Stevens, Jarrad
• Format: Journal Article
• Language: English
• Published: Paris Springer Paris 01-07-2023; Springer Nature B.V
• Subjects: Bisphosphonates; Fractures; Length of stay; Medicine; Medicine & Public Health; Original Article; Surgical Orthopedics; Traumatic Surgery; Bisphosphonate; Radiological outcome; Atypical femoral fracture; Functional outcome
• ISSN: 1432-1068; 1633-8065; 1432-1068
• DOI: 10.1007/s00590-022-03314-y

Purpose
Bisphosphonates are commonly used medication for the treatment of osteoporosis, and a well-established complication of this medication is bisphosphonate-associated atypical femur fractures (BAAFFs). The aim of this study was to assess the post-operative functional and radiographic outcomes of surgically treated BAAFFs.
Methods
An analysis of patients treated at a university-affiliated institution was performed. Patients who had undergone surgical fixation for a subtrochanteric or shaft of femur fracture which had been classified as atypical and treated with bisphosphonate therapy at the time of fracture were included. The outcome measures assessed included post-operative complications, length of stay, discharge destination, post-operative function, independence in activities of daily living (ADLs) and fracture union.
Results
Twenty patients were included in this study with a mean age of 75.2 years. The cohort was predominantly female. The average duration of bisphosphonate therapy was 7.35 years. Nine patients had contralateral bisphosphonate-related stress reactions at the time of their initial fracture and underwent prophylactic surgical intervention. The majority of patients received cephalomedullary nail fixation (95%) with more than half (65.0%) of the cohort experiencing one or more post-operative complications. The median length of stay was 6.5 days and 50% of the cohort required inpatient rehabilitation. At final review, independent mobilisation was recorded in only 10.0% of patients, and 70% of patients were dependent with their ADLs at their latest follow-up. Average follow-up was 8 months, and only six cases demonstrated union at the six-month review, with delayed union between 9 and 12 months being common.
Conclusion
Patients with BAAFFs experience high rates of complications, record poor post-operative functional outcomes, and demonstrate a delayed time to union. Nearly half of our cohort had radiographic evidence of bilateral pathology.