To investigate the diagnostic value of ultrasound performed by a lay experimenter compared to standard radiographic imaging (or standard x-ray) in the detection of fractures in patients with closed acute ankle trauma and positive Ottawa ankle rules

Selection of patients is according to the criteria detailed below. If the patient is deemed eligible for the study, he will be asked to read and sign the informed consent. Besides standard history taking, physical examination and radiographic imaging, a standardized ultrasound examination of the ankle joint will be performed by a lay experimenter.

Care will be provided by the attending physician and, according to "standard of care", treatment decisions will be based on history taking, physical examination and conventional ankle x-ray series. Sonographic results will not be used for this purpose. All ankle x-ray series will be reviewed by a senior resident radiologist.

Inclusion Criteria:

Any adult patient with acute ankle trauma

+ one or more criteria of the Ottawa ankle rules :

• Inability to walk 4 steps immediately after the trauma or in the emergency room,
• pain at the level of the internal or external malleolus (the distal 6 cm) or the base of the 5th metatarsal bone.

Exclusion Criteria:

• Any patient under the age of 18 years
• Any patient unable to sign the informed consent
• Skin lesions contraindicating sonography (e.g. open fracture wound, … )
• An unstable patient whose inclusion in the study would delay vital treatment

Any adult patient presenting to the emergency services of the CHU Saint Pierre