Risk factors for nonunion of ulnar styloid fractures associated with distal radius fractures
Methods: A total of 41 patients with USFs associated with DRFs, treated either surgically or conservatively, were retrospectively evaluated. Fractures were classified based on the treatment modality (surgical/conservative), demographic data, and radiographic characteristics. The Fernandez classification system was used to categorize DRFs. USF displacement was stratified into two groups: displacement >2 mm and <2 mm. Union and nonunion rates were compared across all parameters.
Results: Of the 41 cases included, 12 DRFs were managed surgically with plate-screw fixation, while 29 were treated conservatively with closed reduction and casting. Union was achieved in 35 cases, whereas nonunion was observed in 6. A statistically significant correlation was found between USF displacement >2 mm and nonunion. No significant association was observed between nonunion and other variables, including treatment modality, age, sex, laterality, or fracture classification.
Conclusions: The development of nonunion in USFs accompanying DRFs is not significantly influenced by treatment modality, age, sex, fracture classification, or side of involvement. However, a displacement of the USF greater than 2 mm is associated with a significantly increased risk of nonunion.
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Article Information
- Article Type Research Article
- Submitted February 21, 2026
- Published July 3, 2025
- Issue Vol. 11 No. 4 (2025)
- Section Research Article
