Transcript Cervical Spine Workshop

Cervical Spine Workshop
Chris Dillon, MD
Regions Emergency Medicine
Residency Program
Why is this important?
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Cervical spine injuries are both common and
potentially devastating.
Incidence(USA)
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7,000 to 10,000 patients with cervical spine
injuries who present for treatment annually.
An estimated 5,000 additional patients with
cervical spine injuries die at the scene of the
accident.
Half of cervical spine injuries are associated
with spinal cord injury.
Consequences of neck injuries range from
simple neck pain, to quadriplegia, or even
death
Spinal cord injury occurs at the time of
trauma in 85% of patients and as a late
complication in 15%.
Delayed recognition of an injury or improper
stabilization of the cervical spine may lead
to irreversible spinal cord injury and
permanent neurologic damage.
Who and why
• Spinal cord injury most
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often occurs in teenagers
and young adults.
Mean age 30.7, most
commonly occurs at age
19
82% males
motor vehicle accident
(50%)
falls (25%)
sports injuries (10%).
Cost
• Direct costs for the first year after injury
• High of $417,067 for ventilator dependent
quadriplegics patients to a low of
$122,914 in the group with near normal
neurologic function.
• Indirect costs often greatly exceed the
direct costs.
We see these patients every day
• Due to high morbidity
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and mortality of injuries
Regions Hospital EMS
Guidelines
“Backboard patient with
C-collar if patient
complains of head, neck,
or back pain, or if
suggested by mechanism
of injury, or if history is
unreliable due to
unconsciousness or
altered mental status.”
Anatomy and types of injury
Upper Cervical Spine Injuries
• Most common injury is flexion.
• Fracture of odontoid process.
• Extension injuries may occur,
but are rare.
• Rotation-rare, possible
unilateral facet joint
dislocation.
• Axial loading-fracture of
thinner parts of atlas anteriorly
and posteriorly
• Neurologic deficit is rare
because of size of vertebral
foramen.
• The atlas articulates with the occipital
condyle superiorly and the axis inferiorly.
Atlanto-occipital articulation is important in
the flexion and extension of the neck.
• Atlas-axis articulation is important in the
lateral rotation of the neck.
Lower Cervical Spine Injuries
C3-C7
• Spinal Canal less spacious
• Injuries associated with
forces applied to spine
– Flexion-Dislocated facets
and fracture.
– Extension-Damage to
anterior structures and
compression of posterior
structures.
– Facet joints at 45º-lateral
rotation is limited, but
injuries may still occur.
– Axial loading-combined
with flexion injury.
Normal Anatomy-C4
• Typical cervical vertebra
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of C3 - C7.
Vertebral body is equal in
height anteriorly and
posteriorly.
Vertebra articulates with
the next vertebra at the
body and the articular
processes.
Vertebral artery passes
through the transverse
foramen.
Stability
The determination of whether a given
injury is stable is extremely important
in the initial evaluation of cervical
spine trauma. The stability of the
cervical spine is provided by the two
vertical columns.
Anterior column consists of the vertebral
bodies, the disc spaces, the anterior
and posterior longitudinal ligaments
and annulus fibrosus.
Posterior column consists of the pedicles,
facets and apophyseal joints, laminar
spinous processes and the posterior
ligament complex.
Generally speaking, if one of the two
columns is intact, the injury is stable, if
both columns are disrupted, the injury
is unstable.
Plain films
• Plain films provide the quickest way to survey
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the cervical spine
An adequate spine series includes three views:
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true lateral view (which must include all seven.
cervical vertebrae as well as the C7-T1 junction)
AP view.
open-mouth odontoid view.
Lateral View
• The single most important radiographic examination of the acutely
injured cervical spine is the horizontal-beam lateral radiograph that
is obtained before patient is moved. This film should be obtained
and examined before any other films are taken. All 7 cervical
vertebrae and C7-T1 junction must be visualized because the
cervicothoracic junction is a common place for traumatic injury.
Visualization of C7-T1 may be limited by the amount of soft tissue in
the shoulder region and can be enhanced by:
1. traction on arms if no arm injury is present, or,
2. swimmer's view (taken with one arm extended over the head).
Lateral view
AP and Open-Mouth Views
• The complete radiographic examination includes AP and
open-mouth views.
If there are no obvious fractures or dislocations on the
lateral view and the patient's condition permits, then
proceed with the AP and the open-mouth views.
It is important to obtain technically adequate films. The
most frequent cause of overlooked injury is an
inadequate film series. Patient should be maintained in
cervical immobilization, and plain films should be
repeated or CT scans obtained until all vertebrae are
clearly visible.
The AP view and Odontoid view are obtained as follows
AP/Odontoid
AP
Odontoid
CT
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Up to 20 % of fractures are missed on conventional radiographs. CT can help.
CT scan is not mandatory for every patient with cervical spine injury. Most injuries can be
diagnosed by plain films. However, if there is a question on the radiograph, CT of the cervical
spine should be obtained. CT scan are particularly useful in fractures that result in neurologic
deficit and in fractures of the posterior elements of the cervical canal (e.g. Jefferson's fracture)
because the axial display eliminates the superimposition of bony structures.
The advantages of CT are:
1. CT is excellent for characterizing fractures and identifying osseous compromise of the vertebral
canal because of the absence of superimposition from the transverse view. The higher contrast
resolution of CT also provides improved visualization of subtle fractures.
2. CT provides patient comfort by being able to reconstruct images in the axial, sagittal, coronal,
and oblique planes from one patient positioning.
The limitations of CT are:
1. difficult to identify those fractures oriented in axial plane (e.g. dens fractures).
2. unable to show ligamentous injuries.
3. relatively high costs.
Sagittal, coronal, 3D reconstructions are possible.
CT
MRI
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MRI is indicated in cervical fractures that have spinal canal involvement, clinical
neurologic deficits or ligamentous injuries. MRI provides the best visualization of the
soft tissues, including ligaments, intervertebral disks, spinal cord, and epidural
hematomas.
The advantages of MRI are:
1. excellent soft tissue constrast, making it the study of choice for spinal cord survey,
hematoma, and ligamentous injuries.
2. provides good general overview because of its ability to show information in
different planes (e.g. sagital, coronal, etc.).
3. ability to demostrate vertebral arteries, which is useful in evaluating fractures
involving the course of the vertebral arteries.
4. no ionizing radiation.
The disadvantages of MRI are:
1. loss of bony details.
2. relatively high cost.
Here is an example of a MRI image of the cervical spine demostrating a ligamentous
injury. Notice that the spinal cord is also very well delinated. A dens fracture is not
obvious on the lateral film, but is clearly revealed on MRI.
Evaluation of images
• A adequacy
• A alignment
• B bone
• C cartilage
• D disc
• S soft tissue
Lateral View
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The lateral view is the most important film of all.
Interpretation follows the mnemonic AABCDS.
First, is the film Adequate?
An adequate film should include all 7 vertebrae
and C7-T1 junction.
It should also have correct density and show the
soft tissue and bony structures well.
Alignment
• Assess four parallel lines. These are:
1. Anterior vertebral line (anterior margin of vertebral bodies)
2. Posterior vertebral line (posterior margin of vertebral bodies)
3. Spinolaminar line (posterior margin of spinal canal)
4. Posterior spinous line (tips of the spinous processes)
These lines should follow a slightly lordotic curve, smooth and
without step-offs. Any malalignment should be considered evidence
of ligmentous injury or occult fracture, and cervical spine
immobilization should be maintained until a definitive diagnosis is
made.
Alignment
Bony Landmarks
• Trace the unbroken outline of each vertebrae
(including Odontoid on C2). The vertebral bodies
should line up with a gentle arch (normal
cervical lordosis) using the anterior and posterior
marginal lines on the lateral view. Each body
should be rectangular in shape and roughly
equal in size although some variability is allowed
(overall height of C4 and C5 may be slightly less
than C3 and C6) . The anterior height should
roughly equal posterior height (posterior may
normally be slightly greater, up to 3mm).
Bony Landmarks
Bony Landmarks
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Pedicles project posteriorly to support the articular pillars, forming the
superior and inferior margins of the intervertebral foramen. The left and
right pedicels should superimpose on true lateral views. If fracture is
suspected, get oblique views or CT.
• Facets: the articular pillars are osseous masses connected to the
posterolateral aspect of vertebral bodies via the pedicles. The facet joints
are formed between each lateral mass. On the lateral view, the lateral
masses appear as rhomboid-shaped structures projecting downward and
posterior. "Double cortical lines" results from slight obliquity from lateral
projection. The distance of the joint space should be roughly equal at all
levels.
• Lamina: the posterior elements are seen poorly on the lateral film. They
are best demostrated by CT.
• Spinous process: generally get progressively larger in the lower vertebral
bodies. The C7 cervical spine is usually the largest.
Bony Landmarks
Cartilaginous Space
• The Predental space (distance from dens to C1
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body) should not measure more than 3 mm in
adults and 5mm in children. If the space is
increased, a fracture of the Odontoid process or
disruption of the transverse ligament is likely. If
fracture is suspected, CT should be obtained. If
ligamentous disruption is suspected, a MRI
should be obtained.
Predental space should be:
– < 3 mm in adults.
Predental space
Disc Spaces
• Disc spaces should be roughly equal in
height at anterior and posterior margins.
• Disc spaces should be symmetric.
• Disc space height should also be
approximately equal at all levels. In older
patients, degenative diseases may lead to
spurring and loss of disc height.
Disc Spaces
Soft Tissue Space
• Preverteral soft tissue swelling is important in trauma because it is
usually due to hematoma formation secondary to occult fractures.
Unfortunately, it is extremely variable and nonspecific.
Maximum allowable thickness of preverteral spaces is as follows:
Nasopharyngeal space (C1) - 10 mm (adult)
Retropharyngeal space (C2-C4) - 5-7 mm
Retrotracheal space (C5-C7) - 14 mm (children), 22 mm (adults).
Soft tissue swelling in symptomatic patients should be considered an
indication for further radiographic evaluation. If the space between
the lower anterior border of C3 and the pharyngeal air shadow is >
7 mm, one should suspect retropharyngeal swelling (e.g.
hemorrhage). This is often a useful indirect sign of a C2 fracture.
Space between lower cervical vertebrae and trachea should be < 1
vertebral body.
Soft Tissue Space
AP View
• Alignment on the A-P view should be evaluated using
the edges of the vertebral bodies and articular pillars.
The height of the cervical vertebral bodies should be
approximately equal on the AP view.
The height of each joint space should be roughly equal
at all levels.
Spinous process should be in midline and in good
alignment. If one of the spinous process is displaced to
one side, a facet dislocation should be suspected.
AP
Odontoid View
• Adequate?
• An adequate film should include the entire odontoid and the lateral borders of C1-C2.
• Alignment?
• Occipital condyles should line up with the lateral masses and superior articular facet
of C1.
The distance from the dens to the lateral masses of C1 should be equal bilaterally
Any asymmetry is suggestive of a fracture of C1 or C2 or rotational abnormality. It
may also be caused by tilting of the head, so if the vertebrae is shifted in on one
side, then it should be shifted out on the other side.
The tips of lateral mass of C1 should line up with the lateral margins of the superior
articular facet of C2. If not, a fracture of C1 should be suspected.
• Bony Margins.
the Odontoid should have uninterrupted cortical margins blending with the body of
C2.
Odontoid View
Mechanism of Injury
• The cervical spine may be subjected to
forces of different directions and
magnitude. The most common
mechanisms of cervical spine injury are
hyperflexion, hyperextension and
compression.
Hyperflexion
• Excessive flexion of the
neck in the sagital plane.
It results in disruption of
the posterior ligament. A
common cause of
hyperflexion injury is
diving in shallow water,
which may result in
flexion tear drop fracture.
Hyperextension
• Excessive extension
of the neck in the
sagital plane. A
common cause of
hyperextension injury
is hitting the dash
board in MVA, which
may result in
Hangman's fracture.
Axial compression
• Force applied directly
over the vertex in the
caudal direction. This
compression force
"like smashing a
cracker" may result in
Jefferson fracture, a
bursting fracture on
the atlas.
Atlanto-occipital
Disassociation
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Description: Disruption of the atlanto-occipital junction involving the
atlanto-occipital articulations.
Mechanism: Hyperflexion or hyperextension.
Radiographic features:
1. Malposition of occipital condyles in relation to the superior articulating
facets of the atlas.
2. Increased ratio of Basion - spinolaminar line of C1 to Opisthion posterior cortex of C1 anterior arch for incomplete anterior atlanto-occipital
dislocation. (Refer to atlanto-occipital alignment for further explaination).
3. Cervicocranial prevertebral soft tissue swelling.
Stability: unstable
Atlanto-occipital
Disassociation
Jefferson Fracture
• Description: compression fracture of the bony ring of vertebra C1,
characterized by lateral masses splitting and transverse ligament
tear.
Mechanism: axial blow to the vertex of the head (e.g. diving
injury).
Radiographic features: the key radiographic view is the AP open
mouth, which shows displacement of the lateral masses of vertebrae
C1 beyond the margins of the body of vertebra C2. A lateral
displacement of >2 mm or unilateral displacement may be indicative
of a C1 fracture. CT is required to define the extent of fracture and
to detect fragments in the spinal canal.
Stability: unstable
Jefferson Fracture
Jefferson Fracture
Odontoid Fractures
• Radiographic features: fracture is best seen
on lateral view.
Fracture of the odontoid should be suspected if
there is an anterior tilt of odontoid on lateral
view. The lucent fracture line may be better
delineated by plain film tomogram or CT.
Sometimes the only sign of fracture may be just
prevertebral soft tissue swelling. Odontoid
fractures are generally divided into three types.
Dens Fracture Type I
• Type I Odontoid
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fracture: fracture in
superior tip of the
odontoid.
Potentially unstable.
Rare fracture.
Dens Fracture Type II
• Type II Odontoid
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Fracture: fracture at
base of odontoid.
most common type of
odontoid fracture.
unstable fracture.
Dens Fracture Type II
Dens Fracture Type III
• Type III Odontoid
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Fracture: fracture
through base of
odontoid into body of
axis.
It has the best
prognosis.
Dens Fracture Type III
Hangman's Fracture
• Description: fractures through the pars interaticularis of the axis
resulting from hyperextension and distraction.
Mechanism: hyperextension (e.g. hanging, chin hits dashboard in
MVA).
Radiographic features: (best seen on lateral view)
1. Prevertebral soft tissue swelling.
2. Avulsion of anterior inferior corner of C2 associated with rupture
of the anterior longitudinal ligament.
3. Anterior dislocation of the C2 vertebral body.
4. Bilateral C2 pars interarticularis fractures.
Stability: unstable
Hangman's Fracture
Flexion Teardrop Fracture
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Description: posterior ligament disruption and anterior compression
fracture of the vertebral body which results from a severe flexion injury.
Mechanism: hyperflexion and compression (e.g. diving into shallow water)
Radiographic features: (best seen on lateral view)
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Prevertebral swelling associated with anterior longitudinal ligament tear.
Teardrop fragment from anterior vertebral body avulsion fracture.
Posterior vertebral body subluxation into the spinal canal.
Spinal cord compression from vertebral body displacement.
Fracture of the spinous process.
Stability: unstable
Flexion Teardrop Fracture
Flexion Teardrop Fracture
Bilateral Facet Dislocation
• Description: complete anterior dislocation of the vertebral body
resulting from extreme hyperflexion injury. It is associated with a
very high risk of cord damage.
Mechanism: extreme flexion of head and neck without axial
compression.
Radiographic features: (best seen on lateral view)
1. Complete anterior dislocation of affected vertebral body by half or
more of the vertebral body AP diameter.
2. Disruption of the posterior ligament complex and the anterior
longitudinal ligament.
3. "Bow tie" or " bat wing" appearance of the locked facets.
Stability: unstable
Bilateral Facet Dislocation
Unilateral Facet Dislocation
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Description: facet joint dislocation and rupture of the apophyseal joint
ligaments resulting from rotatory injury of the cervical vertebrae.
Mechanism: simultaneous flexion and rotation
Radiographic features: (best seen on lateral or oblique views)
1. Anterior dislocation of affected vertebral body by less than half of the
vertebral body AP diameter.
2. Discordant rotation above and below involved level.
3. Facet within intervertebral foramen on oblique view.
4. Widening of the disk space.
5. "Bow tie" or "bat wing" appearance of the overriding locked facets.
Stability: stable
Unilateral Facet Dislocation
Anterior Subluxation
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Description : disruption of the posterior ligamentous complex resulting from hyperflexion. It
may be difficult to diagnose because muscle spasm may result in similar findings on the
radiograph. Subluxation may be stable initially, but it associates with 20%-50% delayed
instability. Flexion and extension views are helpful in further evaluation.
Mechanism: hyperflexion of neck
Radiographic features:
1. Loss of normal cervical lordosis.
2. Anterior displacement of the vertebral body.
3. Fanning of the interspinous distance.
Radiographic features of unstable injury:
1. Anterior subluxation of more than 4mm.
2. Associated compression fracture of more than 25 % of the affected vertebral body.
3. Increase or decrease in normal disk space.
4. Fanning of the interspinous distance.
Clay Shoveler's Fracture
• Description: fracture of a spinous process C6-T1
Mechanism: powerful hyperflexion, usually combined with
contraction of paraspinous muscles pulling on spinous processes
(e.g. shoveling).
Radiographic features: (best seen on lateral view)
1. Spinous process fracture on lateral view.
2. Ghost sign on AP view (i.e. double spinous process of C6 or C7
resulting from displaced fractured spinous process).
Stability: stable
Clay Shoveler's Fracture
Wedge Fracture
• Description: compression fracture resulting from
flexion.
Mechanism: hyperflexion and compression
Radiographic features:
1. Buckled anterior cortex.
2. Loss of height of anterior vertebral body.
3. Anterosuperior fracture of vertebral body.
Stability: stable
Wedge Fracture
Burst Fracture
• Description: fracture of C3-C7 that results from
axial compression. Injury to spinal cord,
secondary to displacement of posterior
fragments, is common. CT is required for all
patient to evaluate extent of injury.
Mechanism: axial compression
Stability: stable
Burst Fracture
Classification
• By stability
• Stable
– Anterior subluxation
Unilateral interfacetal dislocation
Simple wedge fracture
Burst fracture, lower cervical spine
Clay Shoveler's fracture
• Unstable
– Anterior subluxation
Bilateral interfacetal dislocation
Flexion teardrop fracture
Hangman's fracture
Jefferson fracture of atlas
Management
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General Principles
Outcome for the spine trauma patient often depends upon action
taken by the emergency team in the first 6 to 12 hours after injury. The
main objective in cervical trauma management is to prevent cord injury and
to minimize any secondary injuries to spinal cord tissue as a result of
inadequate immobilization, persistent spinal cord compression, poor blood
flow or oxygenation. The goal is to optimize the environment for the spinal
cord to recover as much as possible.
• If a cervical fracture or dislocation is found. Orthopedic or neurosurgical
consultation should be obtained immediately.
• There are three indications for surgical intervention in cervical spine trauma.
– Neurologic deficit
– Spinal instability
– Intractable pain
Management
• Some fractures, such as unilateral facet dislocation, may
required skeletal traction and reduction. Physicians
should perform these procedures with minimum amont
of sedation so that the patient can provide instant
neurologic feedback.
• High suspicion for cervical fracture should be maintained
in all trauma situations because there are no signs of
neurologic injury in many cervical fractures. Cervical
immobolization is usually achieved by a Philadelphia-type
collar or a halo vest.
Management of Specific
Fractures
• Jefferson fracture is treated with halo immobilization for 12
weeks, which usually results in primary union of the ring of C1 and
stability of C1 with respect to C2. Surgical fusion may be needed if
there is atlantoaxial instability after removal of halo.
• Hangman's fracture is unstable. It usually heals with halo
immobilization for 12 weeks. Surgical fusion is rarely indicated
• Odontoid fracture:
– Type I is rare. It usually does not have any neurologic symptoms. It is
treated with Philadelphia collar.
– Type II is the most difficult type to treat in the halo vest. Even with
proper management, the nonunion rate is still as high as 30-60%. If
nonunion persists, surgical posterior fusion is indicated.
– Type III is treated with halo immobilization. It usually has a high rate
of union.
Management of Specific
Fractures
• Fractures and dislocations of lower cervical spine:
• Vertical compression fractures are normally treated initially with
traction to reduce fragmentation and subsequently with halo vest.
They tend to heal well with halo immobilization
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• Unilateral facet dislocations do fairly well with halo
immobilization.
• Bilateral facet dislocations are treated conservatively. The facet
joints are reduced and immobilized. The posterior ligament usually
heals poorly.
• Clay Shoveler's fractures are treated with soft collar for comfort.
Prognosis is excellent.
Who needs imaging?
• Not all trauma patients with a significant
injury need c-spine films.
Canadian C-spine Rule
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Context High levels of variation and inefficiency exist in current clinical practice regarding use of cervical spine
(C-spine) radiography in alert and stable trauma patients.
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Objective To derive a clinical decision rule that is highly sensitive for detecting acute C-spine injury and will allow
emergency department (ED) physicians to be more selective in use of radiography in alert and stable trauma
patients.
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Design Prospective cohort study conducted from October 1996 to April 1999, in which physicians evaluated
patients for 20 standardized clinical findings prior to radiography. In some cases, a second physician performed
independent interobserver assessments.
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Setting Ten EDs in large Canadian community and university hospitals.
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Patients Convenience sample of 8924 adults (mean age, 37 years) who presented to the ED with blunt trauma
to the head/neck, stable vital signs, and a Glasgow Coma Scale score of 15.
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Main Outcome Measure Clinically important C-spine injury, evaluated by plain radiography, computed
tomography, and a structured follow-up telephone interview. The clinical decision rule was derived using the
coefficient, logistic regression analysis, and 2 recursive partitioning techniques.
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Results Among the study sample, 151 (1.7%) had important C-spine injury. The resultant model and final
Canadian C-Spine Rule comprises 3 main questions: (1) is there any high-risk factor present that mandates
radiography (ie, age 65 years, dangerous mechanism, or paresthesias in extremities)? (2) is there any low-risk
factor present that allows safe assessment of range of motion (ie, simple rear-end motor vehicle collision, sitting
position in ED, ambulatory at any time since injury, delayed onset of neck pain, or absence of midline C-spine
tenderness)? and (3) is the patient able to actively rotate neck 45° to the left and right? By cross-validation, this
rule had 100% sensitivity (95% confidence interval [CI], 98%-100%) and 42.5% specificity (95% CI, 40%44%) for identifying 151 clinically important C-spine injuries. The potential radiography ordering rate would be
58.2%.
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Conclusion We have derived the Canadian C-Spine Rule, a highly sensitive decision rule for use of C-spine
radiography in alert and stable trauma patients. If prospectively validated in other cohorts, this rule has the
potential to significantly reduce practice variation and inefficiency in ED use of C-spine radiography.
JAMA. 2001;286:1841-1848
Canadian C-spine Rule
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For patients alert w/GCS=15, stable (SBP>90, RR=10-24):
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(1) Any high risk factor that mandates xray?
--age>65 y/o or
--dangerous mechanism (fall>5 stairs, axial load to head, mvc>60 mph, rollover, ejection) or
--paresthesias in ext
**if yes then xray; if no then #2
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(2) Any low risk factor that allows safe assessment of ROM
--simple rear-end mvc or
--sitting position in ED or
--ambulatory at any time or
--delayed onset of neck pain or
--absence of midline c-spine tend
**lf no then xray; lf yes then to #3
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(3) Able to actively rotate neck 45 degrees left & right?
**if no then xray; if yes then no xray
NEXUS
(National Emergency X-ray Utilization Study)
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Background: Because clinicians fear missing occult cervical-spine injuries, they obtain cervical
radiographs for nearly all patients who present with blunt trauma. Previous research suggests
that a set of clinical criteria (decision instrument) can identify patients who have an extremely low
probability of injury and who consequently have no need for imaging studies.
Methods: We conducted a prospective, observational study of such a decision instrument at 21
centers across the United States. The decision instrument required patients to meet five criteria in
order to be classified as having a low probability of injury: no midline cervical tenderness, no
focal neurologic deficit, normal alertness, no intoxication, and no painful, distracting injury. We
examined the performance of the decision instrument in 34,069 patients who underwent
radiography of the cervical spine after blunt trauma.
Results: The decision instrument identified all but 8 of the 818 patients who had cervical-spine
injury (sensitivity, 99.0 percent [95 percent confidence interval, 98.0 to 99.6 percent]). The
negative predictive value was 99.8 percent (95 percent confidence interval, 99.6 to 100 percent),
the specificity was 12.9 percent, and the positive predictive value was 2.7 percent. Only two of
the patients classified as unlikely to have an injury according to the decision instrument met the
preset definition of a clinically significant injury (sensitivity, 99.6 percent [95 percent confidence
interval, 98.6 to 100 percent]; negative predictive value, 99.9 percent [95 percent confidence
interval, 99.8 to 100 percent]; specificity, 12.9 percent; positive predictive value, 1.9 percent),
and only one of these two patients received surgical treatment. According to the results of
assessment with the decision instrument, radiographic imaging could have been avoided in the
cases of 4309 (12.6 percent) of the 34,069 evaluated patients.
Conclusions: A simple decision instrument based on clinical criteria can help physicians to
identify reliably the patients who need radiography of the cervical spine after blunt trauma.
Application of this instrument could reduce the use of imaging in such patients.
N Engl J Med 2000;343:94-9.
NEXUS
• Radiography is not recommended if a patient meets all of the
following criteria:
• Absence of tenderness at the posterior midline of the C-spine
• Absence of a focal neurologic deficit
• Normal level of alertness
• No evidence of intoxication
• Absence of clinically apparent pain that might distract the patient
from the pain of a C-spine injury
Comparison
• Among the 8283 patients, 169 (2.0 percent) had
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clinically important cervical-spine injuries. In 845 (10.2
percent) of the patients, physicians did not evaluate
range of motion as required by the CCR algorithm
prospective cohort study in nine Canadian emergency
departments comparing the CCR and NLC as applied to
alert patients with trauma who were in stable condition
CCR was more sensitive than the NLC (99.4 percent vs.
90.7 percent, P<0.001) and more specific (45.1 percent
vs. 36.8 percent, P<0.001
For alert patients with trauma who are in stable
condition, the CCR is superior to the NLC with respect to
sensitivity and specificity for cervical-spine injury, and its
use would result in reduced rates of radiography
Clinical clearance
• Evaluate
• Strength
• Sensation
• Tenderness
• ROM
• ?image
• Clear
Initial immobilization
References
• Stiell IG, Wells GA, Vandemheen K, et al. The Canadian
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Cervical Spine Radiography Rule for alert and stable
trauma patients. JAMA 2001;286:1841-8.
Stiell IG, Clement C, McKnight RD, et al. The Canadian
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