Sensitivity of plain pelvis radiography in children with blunt torso trauma

Plain anteroposterior pelvic radiographs are commonly used to screen children for pelvic fractures or dislocations after blunt torso trauma. The test sensitivity and utility, however, are unclear. We assessed the sensitivity of anteroposterior pelvic radiographs for identifying children with pelvic fractures or dislocations after blunt torso trauma. We hypothesized that anteroposterior pelvic radiographs fail to identify all children with pelvic fractures or dislocations, including patients undergoing operative intervention and those with hypotension.

We conducted a prospective multicenter observational study of children (<18 years) with blunt torso trauma in the Pediatric Emergency Care Applied Research Network. We compared plain anteroposterior pelvic radiographs to the final diagnosis of pelvic fractures or dislocations as documented by the orthopedic faculty physician before emergency department (ED)/hospital discharge. We described the data with descriptive statistics, including 95% confidence intervals (CIs).

Of 12,044 patients enrolled in the parent study, 451 (3.7%; 95% CI 3.4% to 4.1%) had pelvic fractures or dislocations. Of these patients, 65 (14%; 95% CI 11% to 18%) underwent operative intervention and 21 (4.7%; 95% CI 2.9% to 7.0%) had age-adjusted hypotension on initial presentation. In the ED, 382 of the 451 patients underwent plain anteroposterior pelvic radiographs, with a sensitivity of 297 of 382 (78%; 95% CI 73% to 82%) for patients with pelvic fractures or dislocations, 55 of 60 (92%; 95% CI 82% to 97%) for patients undergoing operative intervention, and 14 of 17 (82%; 95% CI 57% to 96%) for patients with hypotension.

Plain anteroposterior pelvic radiographs have a limited sensitivity for identifying children with pelvic fractures or dislocations after blunt trauma, including patients undergoing operative intervention and those with hypotension.