The diagnosis of cervical spine
injuries presents a challenge in emergency practice. The anatomy of
the cervical spine is complex, the spectrum of injuries is broad,
and the consequences of injury, particularly spinal cord injury,
can be devastating. Most serious cervical spine injuries are caused by
high-energy forces. However, unstable injuries can occur following
relatively minor trauma, such as a fall from a standing position,
particularly in the elderly.
Although most cervical spine fractures are radiographically obvious,
10% have subtle radiographic manifestations or even normal
radiographs (Mower et al. 2001). Patients at high risk of injury
(e.g., severe trauma victims) and those with signs of neurologic
injury require imaging with CT and possibly MRI (see Appendix).
Because of the potentially serious consequences of a missed injury,
cervical spine radiographs are ordered whenever there is a chance
of an injury, even if the risk is small. In fact, fewer than 3% of cervical
spine radiographs will reveal injuries.
Two groups of investigators have developed clinical decision
rules with the aim of reducing the number of cervical spine radiographs
ordered, as well as to objectively validate clinical criteria useful
in the decision to order radiographs.
The National Emergency X-Radiography Utilization Study Group
developed the NEXUS Low-Risk Criteria to guide the clinician in “clearing” the
cervical spine without radiography (Table 1) (Hoffman et al. 2000).
In prior empirically derived clinical practice, the “absence
of neck pain” was the major criterion used to clinically
clear the cervical spine. With the NEXUS rule, the more selective
criterion “no midline cervical tenderness” is
Table 1 NEXUS Low-Risk Criteria ||Download (.pdf)
Table 1 NEXUS Low-Risk Criteria
|Cervical spine radiography can be omitted when a patient exhibits all of the following:|
|1. No posterior midline cervical tenderness|
|2. Normal level of alertness|
|3. No evidence of intoxication|
|4. No focal neurologic deficit|
|5. No painful distracting injuries|
The concept of the NEXUS criteria is that in the absence of factors
that interfere with pain perception, patients without midline cervical
tenderness do not need radiography. This holds true irrespective
of the mechanism of injury or the age of the patient.
The NEXUS criteria are not explicitly defined, but instead depend
on the judgment of the clinician. Although this creates imprecision,
it avoids the complexity of a list of items defining each criterion.
Because of the lack of exact definitions, the NEXUS criteria could
be applied differently by different clinicians. The reduction in
radiography could thereby vary considerably.
The safety of using the NEXUS rule was prospectively validated
in a large multicenter trial that included 34,069 patients. A total
of 818 patients had injuries (2.4%), of which 578 (71%)
were clinically significant. The decision rule identified all but