Do initial radiographs agree with crash site mechanism of injury in pelvic ring disruptions? A pilot study.
OBJECTIVE
Direction of injury force inferred from pelvic radiographs may be used in trauma care to predict associated injuries and guide intervention. Our objective was to compare injury direction determined from anteroposterior (AP) pelvic radiographs with injury forces determined from crash site investigation.


METHODS
We studied all 28 subjects from the Crash Injury Research Engineering Network (CIREN) database who met inclusion criteria of pelvic ring disruption, single-event crash, restrained front-seat occupant, diagnostic-quality pelvic radiography, and complete crash investigation data. Assessment of diagnostic quality of pelvic radiography was made by 2 radiologists who were blinded to all other subject information. Crash site investigation data included principal direction of force (PDOF), crash magnitude, and passenger compartment intrusion. An orthopedic trauma surgeon and a fellowship-trained emergency radiologist independently assessed the pelvic radiographs to determine the injury PDOF and the Young-Burgess and Tile fracture classifications, with disputes resolved by an additional emergency radiologist. Agreement between injury forces and pelvic radiographs was assessed using the kappa statistic.


RESULTS
The PDOF was anterior in 9 (32%) and lateral in 19 (68%) subjects. The readers agreed with the crash primary direction of force in 21 (75%) subjects (kappa=0.42). In subjects with lateral PDOF, agreement was 89% (17/19) compared to 44% for anterior PDOF (4/9). Interobserver agreement for the Young and Tile classification schemes was moderate (weighted kappa 0.44 and 0.54, respectively).


CONCLUSIONS
Crash site investigation and pelvic radiography may provide conflicting information about primary direction of injuring forces. Presumed anterior impact based on PDOF is not in consistent agreement with the pattern of injury evident on the AP pelvic radiograph.
Linnau
Ken F
KF
Department of Radiology, Harborview Medical Center, Seattle, Washington 98104-2499, USA.
Blackmore
C Craig
CC
Kaufman
Robert
R
Nguyen
Thuc Nghi-Hoang
TN
Routt
Milton L
ML
Stambaugh
Lloyd E
LE
Jurkovich
Gregory J
GJ
Mock
Charles N
CN
D000063:Accidents, Traffic; D000328:Adult; D016208:Databases, Factual; D005260:Female; D050723:Fractures, Bone / Q000175:diagnosis*; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D015588:Observer Variation; D010384:Pelvic Bones / Q000000981:diagnostic imaging* / Q000293:injuries*; D010865:Pilot Projects; D011859:Radiography; D015203:Reproducibility of Results; D013314:Stress, Mechanical; D014193:Trauma Centers; D016474:Weight-Bearing