Imaging Guidelines for Patients with Buttocks Trauma

Initial Imaging Approach

The American College of Radiology recommends starting with a portable AP pelvis radiograph as the first-line imaging study for patients with direct buttocks trauma, particularly when the mechanism involves high-impact force, to evaluate for unstable pelvic ring injuries, sacral fractures, and hip dislocations 1, 2
The AP pelvis view can identify life-threatening pelvic injuries, including "open book" fractures, vertical shear injuries, and posterior ring disruptions that may require immediate stabilization, with a sensitivity of 68% for sacral fractures and posterior ring injuries 1, 3
The initial AP pelvis radiograph provides rapid triage information and may identify unstable fractures requiring immediate intervention before CT, with the American College of Radiology recommending its use as the initial imaging study 1, 2

For hemodynamically unstable patients, the American College of Radiology recommends obtaining a portable AP pelvis radiograph immediately in the trauma bay without delay, to identify injuries requiring immediate external fixation or angiography 1, 3
For hemodynamically stable patients, the American College of Radiology recommends beginning with an AP pelvis radiograph, then proceeding to CT pelvis with IV contrast if any fracture is identified or if clinical suspicion remains high, with CT scanning having 100% sensitivity and specificity for pelvic fractures 1, 2

The American College of Radiology recommends adding lateral hip views if there is focal hip pain, inability to bear weight, or concern for hip dislocation or proximal femur fracture, to better characterize fracture patterns and guide surgical planning if needed 2, 6

The American College of Radiology recommends obtaining CT pelvis with IV contrast if any fracture is identified on plain radiograph, high-energy mechanism, persistent pain despite negative radiograph, blood at urethral meatus, perineal hematoma, or inability to void, with CT scanning providing superior detail of posterior pelvic ring injuries 1, 2, 3, 9
The CT should include 3D bone reconstructions to better characterize fracture patterns and guide surgical planning if needed, with the American College of Radiology recommending its use to provide superior detail of posterior pelvic ring injuries 1, 3