ERs find assault victim SOP pelvic x-rays unnecessary

September 9, 2009

Pelvic radiographs are extraneous overkill when it comes to imaging assault victims since most patients get a CT scan anyway, according to University of Maryland researchers.

Pelvic radiographs are extraneous overkill when it comes to imaging assault victims since most patients get a CT scan anyway, according to University of Maryland researchers.

The current standard protocol for seriously injured patients includes lateral radiographs of the cervical spine and frontal radiographs of the chest and pelvis. The researchers found out of 357 assault patients given a pelvic x-ray, 276 also had pelvic CT scans, rendering the pelvic radiographs unnecessary.

In a retrospective study, Dr. Michael Mulligan, a professor of radiology and nuclear medicine at the University of Maryland in Baltimore, and colleagues found none of the assault patients at their institution had fractured their pelvis (Emerg Radiol 2009;16:299-301). In fact, six instances of pelvic injuries suspected to be acute on the pelvic radiographs were proven not to be on CT.

“Overcalls such as these may lead to even more radiographs being requested or other imaging studies being employed, like CT,” Mulligan said. “Eliminating initial pelvic radiographs, in this patient group, will result in a monetary cost-saving and a significant reduction in the gonadal x-ray dose to these primarily young patients.”

Though cost-savings are tricky to estimate, at UMD the cost for a single film of the pelvis plus the professional fee for interpretation is roughly $165, which, multiplied by all victims of abuse, could mean saving hundreds of thousands of dollars, according to Mulligan.

More important than cost-savings though, physicians can stop their patients from receiving excess exposure to radiation.

“Although fractures can be missed on single AP views of the pelvis, more than 75% of the patients also had pelvic CT scans that confirmed the normal radiographic impression,” Mulligan said.

More than half (56%) of the patients needed CT scans anyway because they had altered levels of awareness from loss of consciousness, alcohol or drug use, and physical beatings.

“We use the as-low-as-reasonably-achievable standard in our practices regarding radiation dose. But whenever we think there is an opportunity to eliminate unnecessary radiation exposure, we have a duty to investigate and evaluate,” Mulligan said.

Limitations of the study include its retrospective nature. In addition, the history supplied by the patient may not have been complete or truthful.

A larger prospective study would be useful to confirm the findings and to further define the role of pelvic CT imaging in assault patients, Mulligan said.