PURPOSE: The goal of this study was to assess the diagnostic value of FAST ankle ultrasound, performed by non-radiologist specialist physicians, compared to standard X-ray imaging for ankle and foot trauma in the emergency department. Additionally, we analyzed whether other variables, such as demographic characteristics of the included patients, could influence fracture detection with the diagnostic tools used. METHODS: A non-randomized monocentric prospective diagnostic cohort study was conducted on 143 patients. RESULTS: Ankle and foot fractures were more frequently detected by FAST ultrasound compared to standard radiography. Regarding the influence of demographic factors, age and the correlation between Body Mass Index and age significantly influenced the ability to detect fractures. CONCLUSION: FAST ultrasound demonstrated good diagnostic value in routine clinical practice for screening purposes and could be easily applied by non-radiologist specialist physicians. Implementing this approach may reduce time and costs in patient management, thereby aiding in alleviating triage congestion in the emergency department. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION FOR PROSPECTIVELY REGISTERED TRIALS: NCT05528432
21-02-21.