The elimination of routine radiographic views that do not provide additional information serves to reduce the patient's radiation exposure and improve cost-effectiveness. Few studies have looked at the effectiveness of performing additional oblique views of extremities in trauma cases. De Smet and colleagues evaluated how often oblique views revealed abnormalities that were not seen on frontal or lateral views in patients who suffered trauma to extremities.
The study was a prospective review of 1,461 consecutive radiographic examinations of the distal extremities in patients presenting with acute trauma in four family practice centers. The sites included the ankle, foot, toe, wrist, hand, fingers and thumb. The views included standard anteroposterior or posteroanterior, lateral, mortise and oblique views of the injured extremity. Each examination was interpreted by a radiologist and given a diagnostic certainty score using only the frontal and lateral views. Another certainty score was then performed adding the oblique view.
Of the 1,461 examinations performed during the study, 421 (28.8 percent) were interpreted as abnormal using all three views. The addition of the oblique view changed the interpretation in 70 (4.8 percent) of the examinations. Thirty-nine were changed from equivocal to positive or negative, three from positive to negative and 28 from negative to positive. The diagnostically uncertain cases were reduced from 13.9 to 8.4 percent. The oblique view was equally valuable in all the extremities studied.
The authors conclude that the addition of oblique views in examinations of distal extremities involved in acute trauma can reveal more abnormalities and increase confidence in the final diagnostic interpretation. This additional view adds minimal cost but decreases the chance of missing bony injuries in acute trauma to the extremities.