Diagnosis of pelvic fractures in patients with acute pelvic trauma: efficacy of plain radiographs.

Although CT is widely recognized as an important adjunct to plain films in the evaluation of patients with acute pelvic trauma, accurate diagnosis of orthopedic injuries with plain films alone is often important to determine if immediate external fixation is necessary. The purpose of this study was to determine the efficacy of plain radiographs in the detection of pelvic fractures and dislocations in patients with acute pelvic trauma by using CT as the gold standard. CT scans and plain films collected prospectively in 50 patients with acute pelvic injuries were evaluated independently, and fractures and dislocations were identified and tabulated. Of a total of 162 fractures and dislocations seen on CT, only 14 (9%) were misdiagnosed on plain films. None of these misdiagnoses altered patients' management. Sixteen (80%) of 20 cases of intraarticular fragments in the hip joint associated with acetabular fractures were not identified on plain films. We conclude that plain film examination of the patient with pelvic trauma is sufficient to identify virtually all clinically important fractures and dislocations. Plain radiographs alone are not accurate in detecting fracture fragments within the hip joint.