- See: Radiology of the Acetabulum
- instability = cephalic displacement of posterior sacroiliac
complex of at least 5-15 mm on inlet
- look for gap (rather than impaction) posteriorly, & frx of 5th lumbar transverse process or avulsion of sacrospinous ligament;
- Pertinent Radiographs:
- AP view
- Judet View
- Push-Pull Views:
- used to evaluate dynamic displacement of the pelvis;
- these views are obtained as in outlet
view with the examiner pushing on the femur for one view and pulling on it for the other;
- Sacroiliac Views:
- used to visualize the sacroiliac
- pt is positioned as for Judet views w/ central beam directed toward sacroiliac joint
- only CT scan of the pelvis gives well detailed image of SI joint
- neither the iliac or obturator oblique radiographs shows this well;
- Lateral View:
- required if sacral frx
- technique is identical to lateral view of lumbar spine except that it is centered on the sacrum;
- indicated for patients w/ concomitant pelvic frx and hemodynamic instability, especially when there is frx displacement thru the greater sciatic notch
Is a fracture of the transverse process of L5 a predictor of pelvic fracture instability?
Pelvic and Lower Extremity Trauma--Symposium: The Role of Standard Roentgenograms in the Evaluation of Instability of Pelvic Ring Disruption.
The role of standard roentgenograms in the evaluation of instability of pelvic ring disruption
Original Text by Clifford R. Wheeless, III, MD.