When there is a mechanism of injury for C-spinefracture, don’t rely on plain films.
Local EMS meander in early one evening with a very pleasant elderly female from one of the local nursing homes. She has a trip-and-fall story, and she hit her head on some unidentified object. The paramedics have her in full spinal immobilization. There is a small forehead laceration, with bleeding controlled. The patient is pleasantly demented, and has no complaints except for “my head hurts”. She has no neck pain. Vital signs are normal. You clear her off the long spine board, order a medical “why did she fall” work-up, along with CT of the head and C-spine films. She does not take coumadin, and only other PMH is hypertension. About an hour later (it is a good night), the CT head is done and is negative. The radiology tech calls and asks you to look at the lateral c-spine so they can sit the patient up for more films. No problem, you think.
What does the lateral C-spine X-ray show?
This is a good case for several reasons. First, it illustrates that elderly & chronically ill nursing home patients are at significant risk for C-spine fractures with fairly minimal trauma due to osteopenia. These are commonly in the C1-C2 area, a region not often well-imaged by traditional C-spine X-rays, especially in the elderly.
In this case, the findings of the dens fracture on plain film include a minor posterior spinous process mis-alignment (see parallel lines, image below).
In addition,if you follow the line of the posterior longitudinal ligament upward towards the dens, it just disappears—mostly a limitation of technique. Compare this with the normal C-spine (see dotted line, image below), where you can follow this line upward all the way to the back of the dens.
Secondly, this case demonstrates the remarkable superiority of CT scanning vs. plain X-rays for C-spine fracture in general. The greater availability and quality of CT scanning in recent years has allowed us to perform more C-spine CTs for higher risk patients, such as trauma patients (see images below, left and right).
The elderly are a high risk group also, even with minimal mechanism of injury. Just simply add the CT of the C-spine to the head CT scan for the next elderly patient with the “fell down and hit head” story.
John Dallara, MD, practices Emergency Medicine in Virginia and North Carolina, and directs the Emergency Medicine PREP Course. www emprepcourse.com