Plain x-rays frequently fail to reveal cervical spine injuries (CSIs) of blunt trauma victims, especially injuries to the vertebral lamina and lateral masses. Most of these missed injuries are secondary injuries in patients whose primary injury has been identified by the x-ray. However, in a minority of injured patients, plain x-rays fail to detect any injury.
When such plain x-rays appear normal, the search for CSI may be terminated, with no further use of other imaging technologies such as magnetic resonance imaging. For this reason, clinicians should focus on these two high-risk areas when reviewing plain spinal x-rays of blunt trauma victims, suggest the authors of a recent study supported by the Agency for Healthcare Research and Quality (HS08239).
William R. Mower, M.D., of the University of California, Los Angeles School of Medicine, and his colleagues reviewed all types of x-rays performed on blunt trauma victims at 21 hospitals to compile an exhaustive list of all CSIs sustained by each individual. They then compared these injuries with the injuries detected by plain x-ray alone. Plain x-rays revealed 702 of 1,056 CSIs. Plain films failed to detect 98 injuries (occult) present in 60 patients (10.5 percent) and 256 secondary injuries in 510 patients (89.5 percent) who had a visible (sentinel) injury identified. Plain x-rays failed to reveal 58 percent of lateral mass injuries and 64 percent of lamina injuries, making these the most frequent sites of missed injury.
For more information, see "Occult and secondary injuries missed by plain radiography of the cervical spine in blunt trauma patients," by Dr. Mower, John Y. Oh, B.S., Michael I. Zucker, M.D., and Jerome R. Hoffman, M.D., in Emergency Radiology 8, pp. 200-206, 2001.