A new national study indicates that patients with a cervical spinal injury (CSI) may harbor additional spinal damage not visible on regular x-rays. In fact, more than a third of patients who were thought to have low-risk injuries actually have additional damage that may include significant fractures with the potential to produce serious spinal problems if not detected and treated properly.
This study will be published as an early online release in the Annals of Emergency Medicine, stands in the face of previous medical thinking in which patients with certain forms of spinal injury were considered at very low risk of having additional injuries. Because of that low risk, physicians were urged to use plain x-rays and avoid computed tomography (CT) in evaluating these cases.
"These findings are significant because they suggest that CT imaging, which allows physicians to view the spine in much greater detail, is necessary in evaluating all patients who have radiographic evidence of cervical spine injuries," said lead study author Dr. William Mower, professor of emergency medicine at the David Geffen School of Medicine at UCLA. "We found that even among patients with low-risk injuries, more than one third sustained secondary damage that was not diagnosed by plain radiography."
Mower adds that approximately one-fourth of these secondary injuries occurred in another part of the cervical spine, which suggests that at least some of these patients may have actually sustained two separate spinal injuries.
Researchers reviewed patient cases from the National Emergency X-Radiography Utilization Study (NEXUS), which was conducted at 21 centers across the United States.
Study authors found that x-rays failed to detect secondary injuries in 81 of the 224 patients identified with cervical spine injuries – or 36 percent. "We also think that this is likely an underestimate, and the true prevalence of missed injury is probably even greater," said Mower.
The researchers believe that patients with any evidence of cervical spine injury, including those with cervical spine injuries previously considered to be at low risk for secondary injuries, should undergo CT imaging of the entire cervical spine. CT should be obtained both to determine whether secondary injuries are present and to identify those non-contiguous injuries that, in fact, occur in a substantial number of cases.