Presence of bone bruise and adjacent soft-tissue edema have shown a higher association with acute ligamentous injuries (anterior talofibular ligament most common) and tendon abnormalities [53,54] in patients with negative radiographs. MRI can also help exclude Salter 1 fractures in the pediatric population [55]. Radiography Ankle Repeat radiographs are not typically the next study but may be of use to identify early callous formation at an occult fracture line or possible mineralization at a site of intramuscular hematoma if contusion occurred during trauma. Radiographs with better technique may assist in diagnosis of subtle injuries such as the lateral talar process avulsion, which may erroneously be diagnosed as a lateral ankle sprain [37]. Radiography Ankle Stress Views Although ankle stress views are not the typical next best study for this patient group, if there is clinical evidence of instability on physician maneuvers, ankle stress views may be of benefit for identification of occult avulsion injury at ligamentous attachments that may contribute to widening of the joint space on radiographic stress views. US Ankle US is not typically the next imaging study. US may be useful as a secondary evaluation modality for focused evaluation of underlying soft-tissue injuries and ligaments, with the added benefit of dynamic imaging. This includes focused high-resolution US of the peroneal tendons and the superior peroneal retinaculum [56], stress US (during anterior drawer) to assess joint laxity or chondral avulsion fractures associated with lateral ligament injury in children with negative radiographs [57,58], and potential detection of superficial occult fractures at the base of the fifth metatarsal, lateral malleolus, and malleolus [41]. Variant 5: Adult or child 5 years of age or older. Acute trauma to the ankle. No exclusionary criteria present. Radiographs demonstrate fracture or potential osteochondral injury. Next study.
Acute Trauma to the Ankle. Presence of bone bruise and adjacent soft-tissue edema have shown a higher association with acute ligamentous injuries (anterior talofibular ligament most common) and tendon abnormalities [53,54] in patients with negative radiographs. MRI can also help exclude Salter 1 fractures in the pediatric population [55]. Radiography Ankle Repeat radiographs are not typically the next study but may be of use to identify early callous formation at an occult fracture line or possible mineralization at a site of intramuscular hematoma if contusion occurred during trauma. Radiographs with better technique may assist in diagnosis of subtle injuries such as the lateral talar process avulsion, which may erroneously be diagnosed as a lateral ankle sprain [37]. Radiography Ankle Stress Views Although ankle stress views are not the typical next best study for this patient group, if there is clinical evidence of instability on physician maneuvers, ankle stress views may be of benefit for identification of occult avulsion injury at ligamentous attachments that may contribute to widening of the joint space on radiographic stress views. US Ankle US is not typically the next imaging study. US may be useful as a secondary evaluation modality for focused evaluation of underlying soft-tissue injuries and ligaments, with the added benefit of dynamic imaging. This includes focused high-resolution US of the peroneal tendons and the superior peroneal retinaculum [56], stress US (during anterior drawer) to assess joint laxity or chondral avulsion fractures associated with lateral ligament injury in children with negative radiographs [57,58], and potential detection of superficial occult fractures at the base of the fifth metatarsal, lateral malleolus, and malleolus [41]. Variant 5: Adult or child 5 years of age or older. Acute trauma to the ankle. No exclusionary criteria present. Radiographs demonstrate fracture or potential osteochondral injury. Next study.