Metaphyseal comminution in distal radius fractures: a predictor of secondary fragility fractures and the role of osteoporosis treatment.

Metaphyseal comminution in distal radius fracture (DRF) cases might indicate severe osteoporosis. The patients with DRFs and metaphyseal comminution showed 5.2-fold increased secondary fractures compared with those receiving combination osteoporosis therapy. High-risk DRF patients require aggressive osteoporosis management and fracture risk stratification.

Purpose: Distal radius fractures (DRFs) are common in patients with osteoporosis and associated with increased risks for subsequent fractures. Metaphyseal comminution in patients with DRFs may indicate severe osteoporosis and heightened bone fragility. However, its relationship with the risk of secondary fragility fractures remains unclear. This study aimed to evaluate the incidence of secondary fractures in patients with DRFs involving metaphyseal comminution and assess the effectiveness of osteoporosis treatment in reducing this risk.

Methods: In this retrospective cohort study, 134 patients aged ≥ 50 years underwent DRF surgery at a single institution from July 2018 to December 2022. The patients were allocated into groups by the presence (n = 45) or absence (n = 89) of metaphyseal comminution. The primary outcome was secondary fracture incidence. A multivariate Cox model was used, adjusting for age, sex, body mass index, bone mineral density, osteoporosis treatment type, and dementia.

Results: Secondary fractures were significantly more frequent in the comminution group (17.8%) than in the non-comminution group (3.4%) (p = 0.004). Metaphyseal comminution was associated with 5.2-fold increased secondary fracture risk (hazards ratio: 5.2, 95% confidence interval: 1.4-10.7, p = 0.004). The patients administered combination therapy (active vitamin D plus bisphosphonates or anabolic agents) had notably lower secondary fracture rate than did those receiving vitamin D alone (5.6% vs. 15.4%, p = 0.046).

Conclusions: Metaphyseal comminution in patient with DRFs significantly elevated secondary fracture risk; combination osteoporosis therapy might mitigate this risk. These findings underscore the need for robust osteoporosis management in high-risk patients, suggesting metaphyseal comminution should be crucial for fracture risk stratification.