Lim SJ, et al. - Authors ascertained the incidence and risk factors of atypical femoral fractures (AFFs) by performing a multicenter case-control study. They also gauged the impacts of bisphosphonates (BPs) on AFF healing. Among 6644 hip and femoral fractures, the incidence of AFFs was 2.95%. For the development of AFFs, the independent risk factors were osteopenia or osteoporosis, use of BPs, rheumatoid arthritis, increased anterior and lateral femoral curvatures, and thicker lateral femoral cortex. Findings suggested a greater likeliness of the patients with AFFs and BP treatment to have problematic fracture healing than those with TFFs and no BP treatment.

Methods

• Researchers retrospectively reviewed the medical records and radiographs of 6644 hip and femoral fractures of patients from 8 tertiary referral hospitals.
• In order to distinguish AFFs from TFFs, all the radiographs were reviewed.
• They performed univariate and multivariate logistic regression analyses to identify risk factors. Interaction analyses were used to gauge the impacts of BPs on fracture healing.

Results

• Findings suggested that among 6644 hip and femoral fractures, the incidence of AFFs was 2.95% (90 subtrochanter and 106 femoral shaft fractures).
• As per data, all patients were females with a mean age of 72 years, and for an average duration of 5.2 years (range, 1–17 years), 75.5% were exposed to BPs.
• Results demonstrated a significant association of the use of BPs with AFFs (p < 0.001, odds ratio = 25.65; 95% confidence interval = 10.74–61.28).
• For AFFs, other independent risk factors included osteopenia or osteoporosis, rheumatoid arthritis, increased anterior and lateral femoral curvatures, and thicker lateral femoral cortex at the shaft level.
• A significantly higher risk of problematic fracture healing was seen in patients with AFFs using BPs than those with TFFs and no BP treatment; as seen on interaction analyses.