Cervical spine clearance in the obtunded trauma patient
The Alfred Trauma Centre’s experience with flexion-extension xrays
Ilan Freedman – surgical resident, Alfred Hospital
Sumary:
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Introduction:
Cervical spine injuries have been estimated to
occur in 10% of patients with serious head
injury. The potential consequences of missed
injuries can be devastating and may include
quadriplegia and its medical, social and medicolegal costs. Trauma patients thus require early
and accurate cervical spine assessment with an
investigative approach of high diagnostic yield
to prevent further injury and in planning future
care.
Clinical
findings
combined
with
radiological assessment have been used to
evaluate the cervical spine in conscious patients
but the management of patients who are
obtunded (Glasgow Coma Score < 13) and
unable to participate in clinical assessment is
controversial.
Plain
X-Rays
alone
are
inadequate,
with
29
published
studies
demonstrating that plain lateral X-Ray alone
had a sensitivity of only 85%, while a threeview trauma cervical series (lateral, anteroposterior and peg views) improved the
diagnostic sensitivity to only 93%. Various
protocols such as three-view series, five view
series (three view series with addition of supine
oblique views), CT scan of selected neck areas
as an adjunct, CT of whole neck as an adjunct
and MRI as an adjunct have been suggested.
However, there is no national or international
consensus of opinion on the optimal approach
to this situation.
In some Trauma Centers obtunded patients
were consequently previously maintained for a
sustained period in a cervical collar, but this is
associated with a high incidence of pressure
ulcers and may not adequately stabilize the
cervical spine.
The Alfred Hospital receives a large
number of patients with major trauma and a
population at high risk of cervical spine injury.
An institutional policy was consequently
implemented in 1993 which sought to use
passive flexion/extension radiography to further
evaluate the cervical spine. The intention was
an attempt to detect occult injury and to
identify ligamentous instability in unresponsive
trauma patients who had a normal three-view
cervical spine series.
This approach required considerable
time and significant manpower with close
cooperation
between
trauma
physicians,
radiologists, neurosurgeons and radiology
technicians. In addition, the safety of functional
X-rays in unconscious patients has been
debated. An evaluation of all obtunded trauma
patients admitted to the Alfred Emergency
Department during a one year period was
performed, several years after the protocol had
been in place as the standard institutional
practice, to ascertain the efficacy and
appropriateness of passive flexion/extension
radiography.
Method:
clinical and radiographic examination but
obtunded patients are not able to respond to
The diagnostic images, imaging reports and
case notes for all obtunded trauma patients
with potential cervical spine injuries presenting
to the Alfred Hospital Trauma Center during the
questioning and have unreliable physical
examinations.
One option is to leave the
patient in a cervical collar for an extended
period. This assumes that the collar will
period 01 January 1998 to 31 December 1998
were evaluated.
The protocol is detailed in Figure 1. The
initial xray series consisted of lateral, antero-
stabilize the cervical spine and allow healing of
any injury that may be present. The reliance on
the presence of the cervical collar to keep the
neck stabilized may be dangerous and
posterior and peg views and if C7-T1 was not
clearly visualized, swimmer’s views were then
obtained. If these were abnormal or equivocal,
inappropriate. A high degree of mobility of the
cervical spine
patients underwent cervical spine CT and/or
MRI. If the static x-rays were normal, patients
then underwent passive functional x-rays.
These were flexion-extension images with 30
International protocols for assessment of
possible cervical spine injuries in obtunded
patients differ considerably.
degrees of head flexion and extension directed
by the ICU consultant. If these were normal,
the collar was removed. If these were
abnormal, a cervical spine CT and/or MRI was
A retrospective evaluation of all obtunded
trauma patients admitted to the Alfred Hospital
between 01 January 1998 and 31 December
1998 was performed.
done. All x-rays were reviewed by two of three
consultants (neurosurgeon, intensive care
consultant, radiologist) with agreement reached
before films were cleared.
Patients initially underwent
cervical spine series (….)
a
three-view
A missed cervical spine injury can be
Two hundred and three obtunded patients
devastating and may lead to chronic neck pain
or even paralysis.
Trauma Centers around the world have devised
markedly different protocols for dealing with
presented to the trauma centre between
January 01, 1998 and December 31, 1998. One
hundred and ninety five underwent static
this issue and for “clearing” the cervical spine in
such patients.
Prolonged use of cervical collars is associated
cervical x-rays, of which XXXX were normal.
XXXX of these underwent passive flexionextension x-rays, of which XXXX were reported
as normal.
with skin breakdown and ulcerations that
represent not only a significant health issue but
an economic burden as well.
XXXX patient had cervical instability which was
later confirmed by XXX.
XXXX patients were of particular significance to
this study are detailed in table XXX.
Patients who are obtunded are much more
difficult to assess and ultimately clear of
cervical spine injury.
Results:
Discussion:
In the alert conscious patient, the spine may be
confidently assessed by a combination of
The assessment … in obtunded patients is
controversial. We have performed a
retrospective review of all patients with
suspected cervical injuries admitted during a
one year period.
There has internationally been a general
reluctance to perform flexion-extension imaging
However, under the enthusiasm of the
particular neurosurgeons at the Alfred Hospital,
on obtunded patients out of concern that the
patient is not able to …., and that the procedure
is potentially dangerous.
a large series of f-e investigations were
performed during 1998.
It has always been assumed that performing passive flexion/extension in an unconscious
patient is dangerous, as they are unable to guard or complain of pain. However, there has
been limited formal assessment of the safety of this procedure in the literature.
Performing passive functional views is resource-intensive, requiring the patient to be brought
to the department accompanied by the ICU staff and neurosurgeon who performs the
flexion/extension. At least two radiographers are required and the whole process may take up
to two hours to complete.
Discussion
Results:
Four instances of false negative flexion-extension films/reports were revealed.
The first of these was a 26 year old male admitted with a GCS 3 post motor vehicle accident.
Initial c-spine films and functional views reported as normal. One month later complained of
shoulder pain with no focal neurological deficit. CT scan revealed fractured C4 lamina and C4/5
facet joint dislocation. Review of the original functional films did show c4/5 anterolisthesis, that
is the functional film was false negative in initial report, but true positive on review.
2) Fifty two year old male MVA pedestrian GCS 3 on admission. Functional films suspicious for
anterior longitudinal ligament injury (c3/4 retrolisthesis with anterior disc space widening on
extension, returning to normal on flexion). On review functional films again reported as
abnormal. No further imaging done.
3) Twenty year old male, MCA GCS 7 on arrival. Plain films and functional views were reported
as normal, no initial CT. Two weeks later complained of neck pain. CT revealed #c3 lateral
mass, # c4 pedicle and lamina, #c5 facet and C3/4 facet subluxation. On review the functional
images were re-reported as abnormal, i.e. false negative on initial report, true positive on
review.
5) Thirty year old male.
Conclusions:
The flexion-extension imaging procedure itself appears safe in that no patients suffered any
neurological complications as a direct sequalae of the investigation.
However, the procedure has poor sensitivity.
With the medical and medicolegal implications of a missed cervical injury being so enormous,
the Alfred Hospital Trauma Centre has now abandoned the use of f-e.
In 1999, two investigations were added to the routine protocol for all unconscious patients at
the Alfred Hospital. There were fine cut cervical CT + reconstruction, and functional x-rays
using fluoroscopy.
Our data thus far suggests that a cervical screening protocol for unconscious trauma patients
including 2 plain x-rays and early fine-cut CT and reconstruction identified all patients with
cervical fractures or instability. Routine flexion-extension X-Rays have been deleted from the
Alfred Protocol.
Current protocol at the Alfred Hospital now involves fine cut CT.