The Effects of Ulnar Styloid Fractures on Patients Sustaining Distal Radius Fractures

PURPOSE: To determine if ulnar styloid fractures (USF) affect clinical outcome following distal radius fracture (DRF) in adults under 65 years of age. METHODS: This study involved 312 patients (aged 18-64) with surgically and nonsurgically treated DRFs. Patients were followed prospectively at baseline and 3, 6, and 12 months. The primary outcome was the Patient-Rated Wrist Evaluation (PRWE), and secondary outcomes were range of motion and grip strength. The USFs were classified by location (tip, middle, and base) and union status. RESULTS: There were 170 patients with isolated DRFs and 142 with associated USF (64 tip, 32 middle, and 46 base fractures). The mean age of the entire cohort was 48 years with 218 (70%) women. All USFs were treated nonoperatively. There was a trend of higher PRWE scores in DRFs associated with USFs compared to isolated DRFs throughout the study. Associated ulnar styloid base fractures had higher but clinically insignificant PRWE scores than isolated DRFs at 6 and 12 months. Patients with an associated USF had a slower recovery of wrist flexion and grip strength compared to isolated DRF, but values were comparable at 12 months. United USFs and nonunited USFs had similar PRWE scores at all time points. CONCLUSIONS: Adults under 65 years old with DRFs and associated USFs initially have greater pain and disability than those with isolated DRFs; however, this difference dissipated over time and was not significant at one year. No long-term differences in measured impairments were observed, but the presence of an associated USF resulted in a slower recovery of grip strength and wrist flexion. Presence of a USF nonunion did not significantly affect outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.