| ||||||||||||||||||||||||||||||||||||||||||||||||||||
Clearing the Cervical Spine Richard M. Bell, M.D.,FACS Professor of Surgery, University of South Carolina 1. Introduction The idea of protecting the cervical spine of injured patients may not
have been initiated by the ATLS program, but the emphasis placed on this
concept has had profound impact on the management of the trauma patient.
In most respects, the impact has been positive. It is unfortunate that many
have extrapolated "diagnostic imaging" of the cervical spine to
be synonymous with "protection." Patients are immobilized, often,
for prolonged periods, bound to rigid uncomfortable equipment enduring the
risk of aspiration and decubitus ulcers for fear of inadvertent iatrogenic
injury to the spinal cord. Clinicians who are not radiologists nor deal
with trauma on a frequent basis, are reluctant (and understandably so) to
assume the risk of "clearing" the cervical spine and leave the
patient immobilized until someone with the expertise to pronounce "the
neck to be normal" does so. Determining the answer to a series of fundamental questions represents
a safe approach to the process of protecting the patient's neck, as well
as the doctor's. These queries concern the incidence of spine injury, the
findings on a "reliable" physical examination, and the necessary
radiologic assessment of the bony spine. 2. Who is at risk for cervical spine injury? Any patient who sustains significant blunt injury and some individuals
with penetrating neck injuries are at risk for cervical spine fracture.
The ATLS program has emphasized that individuals with blunt injury above
the clavicles have a significant risk of associated cervical spine fracture.
The problem involves defining precisely "significant" risk. The association of supraclavicular injury and cervical spine injury has
been assumed for many years and quoted to be as high as 33%. This author's
review of his personal experience of approximately 7500 patients over 60
months discovered that 13% of patients with cervical spine fractures had
an additional injury above the clavicle." A 16% incidence of cervical
spine injury associated with head injury in fatal accidents was reported
by Alker and colleagues.' Buchoiz et a 12 noted that cervical spine injuries
were frequently associated with head injury sustained in fatal automobile
crashes. Kip and Hunter' reported a 33% association of facial and head injuries
in ski accident victims with cervical spine fractures. Other reports suggest
that the association may not be as significant as originally thought if
one considers specific supraclavicular injuries. Table 1 summarizes the
association with some specific supraclavicular injuries. Additionally, the
records of 1 3,834 patients entered into the North Carolina Trauma Register
were retrospectively examined. Odds ratio calculation did not demonstrate
that patients with skull and/or facial fractures were more likely to have
cervical spine injury.' Multiple other authors have not been able to demonstrate
a greater risk of cervical spinal injury in association with supraclavicular
injury.'-' Andrew and co-workers' could not identify an increased risk of
cervical spine fracture in patients with mandibular fracture, nor Frye et
allo in patients with intracranial haemorrhage. Analysis of the multiple publications which address this risk cannot
demonstrate a definite association between any single isolated in injury
above the clavicle, however ample evidence is available to confirm that
patients with an alteration in their level of consciousness are at increased
risk for cervical spine fracture.' 1-14 Whether the risk of cervical spinal
fracture is greater for those patients with supraclavicular injuries or
not, there is little risk in the conservative approach to these patients
by taking measures to protect the spine until the spine can be appropriately
evaluated by physical examination, and by x-ray if indicated. Table 1. Injury above clavicles and associated cervical spine injury. Clav =clavicular fracture, Head =head injury, inj=injury, and face=facial
fractures. GCS > 14 = scores of 14 and 15. 11 3. Who needs radiographic evaluation of the cervical spine? Patients who present to the emergency department with obvious signs of
cord injury require evaluation of their cervical spine to precisely define
the extent of the bony deformity and to plan specific treatment. Patients
with an altered level of consciousness, regardless of the cause, require
cervical radiographic evaluation. Controversy persists regarding the x-ray
evaluation of the asymptomatic patient to exclude the "occult"
cervical spine fracture. Many reports, a large number of them anecdotical,
suggest the possibility of cervical spine injury in patient with no symptoms
referable to the neck. 15-23 Careful analysis of these isolated reports
employing the template described below fails to corroborate the conclusion
that the truly occult cervical spine fracture exists. Extensive retrospective
and prospective evidence supports the position that: l)alert patients, not
under the influence of drugs or alcohol, 2)who have no complaints of neck
pain or tenderness on palpation of the cervical spine, 3)who have no neurological
findings on physical examination, and 4)who do not have associated injuries
of such magnitude that their presence would distract the patient from perceiving
neck pain or other neurological sequelae, do not require roentgenographic
evaluation of the cervical spine based on the mechanism of injury alone.
The risk of missing a cervical spine fracture approaches 0% utilising these
criteria 21-31. These rules also apply to to the paediatric patient with
the modification that children who are preverbal, less than two years of
age, are considered at high risk and should have xray evaluation of their
cervical spines when the mechanism of injury portends a possible injury
32. These authors also calculated the risk to be 23 times higher in these
high-risk children (7.5% than those considered low-risk who had no cervical
spine injury. Elderly patients also present special problems. The relatively asymptomatic
patient with a cervical spine fracture described by McKee 23 was an 83 year
old man. While there is no apparent data in the literature to suggest that
the process of senescence alone masks the potential symptoms related to
a cervical fracture, sufficient information is available to generate a high
index of suspicion of cervical spine fracture in older patients who have
sustained even seemingly minor injuries33-34. The American College of Radiology(ACRAT) has published "appropriateness
criteria" for obtaining films of the cervical spine of patients with
potential for cervical fracture. A review of current literature by a task
force of radiologic experts agreed unanimously that cervical spine x-rays
were not considered appropriate in patients who are "asymptomatic and
alert,[with a] normal physical examination, with or without [a] cervical
collar [in place]31. Obviation of radiographic evaluation of patients with potential cervical
spine injuries demands that a careful and reliable physical examination
be performed by an experienced physician. In contrast, radiographic evaluation
of the cervical spine does not replace the need for a careful physical examination.
Economic issues and medico-legal considerations perpetuate the debate regarding
who does and who does not require x-ray evaluation of the neck. Hoffman
et al 1 3 suggested that over 600,000 cervical spine series are being performed
in the USA per year at a cost of over $45 million. This estimate was derived
from applying their own evaluation protocols and extrapolating this practice
to the estimated 92 million ED visits per year. If more selective criteria
were applied to determine who needs radiographic evaluation, the cost could
be reduced by over one third. The alternative argument involves the cost
of a missed cervical spine injury. If the prevalence of cervical spine fracture
is 3%, there are approximately 20,000 fractures per year. The estimate number
of missed fractures is 200 and the number of unstable fractures is predicted
to be 10%, or 20 patients per year. Estimating that only half of these patients
experience any adverse sequelae, the cost of medical care and the dollars
paid for litigation nullify the savings. 1 3 Such reasoning assumes that
performing the x-ray examination is effective in identifying all patients
with acute fractures. Most important, however, is the physicians's duty
to protect the patient from further injury. If a screening examination was
available at a reasonable price which was 100% sensitive, with 100% specificity
and a 100% predictive value (+ and -), the issue would be closed. Reality
demonstrates otherwise. 4. How many views are enough? Disagreement regarding the number of views of the cervical spine necessary
to exclude the presence of an acute fracture pervades the literature. The
more expensive radiographic diagnostic modalities, computerized tomography(CT)
and magnetic resonance imaging(MRI), have not been assigned a definitive
position in the investigative armamentarium. Mirvis et al 31 found by a
national survey that one third of all hospitals utilized a protocol employing
a single cross-table lateral view of the cervical spine as the only screening
modality for patients with potential cervical fractures. No evidence can
be found in the literature which supports such a limited evaluation when
x-ray evaluation of the cervical spine is required. Woodring and Lee 3'
reported that 65% of fractures and 45% of subluxations identified in 216
patients were not detected on cross-table lateral films. Thirty-two percent
of these patients, half of whom had unstable injuries, were inaccurately
identified as having "normal" spines. ACRAT, by unanimous consensus, recommends a minimum of three views: l)
a lateral view (to include all seven cervical vertebrae and enough of the
first dorsal vertebrae to demonstrate alignment), 2) an anterior-posterior
projection, and 3) an open mouth odontoid view. McDonald et al 38 and others
31-41 have reported evidence to support the position of this review board.
In McDonald's series the risk of missing an unstable fracture with this
three-view approach was estimated to be less than 1 %. This protocol been
adopted by most Trauma Centers when radiologic evaluation of the cervical
spine is indicated. Others have suggested that the addition of supine oblique
views provide better evaluation of the cervico-thoracic junction and should
be included as a routine part of the screening examination 42-43 . A comparative
study of the three and five view examination does not show any clinical
benefit from the additional two views of the spine as long as the cervico-thoracic
junction is well visualized on the lateral film. The report does document
some cost savings when radiographic evaluation is limited to only three
views. Several authors have suggested that routine CT evaluation of the cervical
spine be employed. Blacksin and Lee 44 reported that the 8% of Cl-C2 fractures
identified in their series were not recognized by plain radiographs. Link
and others 45 corroborated these findings by reportingthat half of the Cl-C2
fractures in their series (l 4% of the cervical injuries in this series)
were not see by plain roentgenograms and only one of the nine occipital
condyie fractures was seen on screening films. Woodring recommends three
view screening examinations but advocates liberal use of CT "when necessary".
Specific indications for CT scanning are not mentioned in this report, but
inability to adequately visualize the extremes of the cervical spine and
the cranio-cervical and cervico-thoracic junction are accepted indications.
In another publication, Woodring and Lee" emphasize the limitations
of the CT scan for cervical spine evaluation, documenting the inadequacy
of the scan to identify the alignment of one vertebral body to another and
therefore the limiting its usefulness in diagnosing subluxations. Tomography,
according to these authors, is thepreferred examination in these circumstances. Ample evidence is available to support the three-view examination as
the initial screening examination of the cervical spine when indicated,
but with several caveats. First, the films must be of excellent quality
and demonstrate the entire cervical spine including the cervico-thoracic
junction. If the latter is not possible, then the swimmer's view or supine
oblique views are the next step. If these views fail to provide adequatevisualization
CT scanning is indicated. An adequate open mouth odontoid view can be difficult
to obtain in the acute setting due to intubation tubes, level of consciousness,
patient cooperation, cervical collars and other contingencies. CT scanning
is suggested in this situation as well. Other imaging studies are obtained
as necessary to define the injury. Table 2. "Fingerprints' of Cervical Spine Injury Flexion Rotary Secondly, the films must be interpreted by those skilled in the evaluation
of cervical spine radiology. Some studies have advocated that an experienced
trauma surgeon and radiologist review the films. Collaborative efforts are
reported to effectively eliminate error in interpretation. The radiologist
can provide useful suggestions for further study as a consultant. Davis
et al" found that inadequate films and inexperience in interpretation
were the most common culprits resulting in missed cervical spine injury. Daffner and colleagues50 have proposed that the mechanism of injury can
be an important guide to the interpretation of the spine radiographs as
vertebral fractures occur in predictable and reproducible patterns. These
"fingerprints" of flexion, extension and rotation injuries are
extremely useful in the identification of fractures and are reproduced in
Table 2. Daffner also prefers a logical approach to reading the cervical spine
films, much analogous to the radiologic "A" represents alignmentand
anatomy, "B" is bony integrity, "C" is cartilage or
joint spaces, "D" is disk spaces and "S" represents
soft tissues. Soft tissue swelling, it is at best a secondary indicator
of cervical spine injury. ' A summary of the ABCD'S of cervical spine film
interpretation is reproduced in Table 3. Table 3. ABCD'S of Cervical Vertebral Injury Alignment/Anatomy Bony integrity Cartilage/Disk space Soft tissue 5. What additional evaluations are required for the patient who complains
of pain, but the standard three-view screening examination does not show
a fracture? This query is relatively easy to resolve. ACRAT recommends that flexion
and extension views be obtained in the vertical posture to detect subluxation.
Routine CT and MRI are not considered appropriate and no consensus was reached
regarding supine oblique vie WS.35 If the flexion and extension films do
not show subluxation and the patient continues to complain of pain, or more
importantly dysesthesia, then MRI or CT myeiography should be considered. 6. What is appropriate evaluation for the obtunded patient without
peripheral neurological abnormalities who had a radiologic screening examination
of the cervical spine which did not demonstrate a fracture or dislocation? This incidence of an unstable cervical spine fracture in a patient who
cannot communicate the presence or absence of neck pain and who has normal
screening films which visualize the entire cervical spine is not known.
Some reports address the dilemma obliquely, but do not specifically consider
the incidence of stable versus unstable fractures. McDonald 38 suggests
that the incidence is "less than 1 %. " Other reports estimate
the incidence may approach 3% to 7%". The absence of specific information
regarding spinal stability does allow this informationto be very useful
on clinical grounds. Age becomes a confounding variable with more occult
injuries found in older patients in some series. 7. When should the cervical collar be removed? Maintaining spinal precautions is not without risk. Decubitus ulceration
of the sacrum has been seen after as little as thirty minutes on a spine
board. Ulceration of the chin, mandibular body/angles, mastoids and occipital
areas have been noted after three days in semi-rigid cervical collars. While
skin loss cannot be equated with the tragedy of developing paraplegia while
the patient is under medical supervision, inability to remove the collars
poses multiple management problems. One group of California workers has
advocated dynamic fluoroscopy of unconscious patients to exclude unstable
ligamentous injury." Only one potentially unstable injury was identified
in 1 1 6 patients and no patient suffered neurological problems as a result
of the examination. This injury was later determined to be "physiologic"
subluxation. This study lends further support to the concept that the incidence
of unstable, cervical spine injury in the presence of adequate and normal
screening examinations must be very low. A review of nearly 7500 entries of trauma register data for a 60 month
period from 1990 at the author's hospital identified 470 patients diagnosed
with acute cervical fractures. No obtunded patient with an adequate three-view
screening examination correctly interpreted by the senior trauma surgeon
and an experienced radiologist was subsequently identified as having an
unstable cervicalfracture. 48. Summary Any patient who sustains blunt injury and those with penetrating injury
to the neck have the potential for cervical spine fracture. The overall
incidence of cervical fractures is low, approximately 3% of all patients
with blunt injury. The concept that any single isolated injury above the
clavicles increases the risk of cervical spine fracture cannot be substantiated.
Alteration in consciousness is associated with an increased incidence of
cervical spine fracture. Alert patients who do not complain of neck pain,
have a normal, reliable physical examination and have no other painful injuries
which would mask symptoms referable to the neck do not need screening x-rays.
No reports of missed fractures have been identified when these criteria
are fulfilled. Considerable cost savings could be recognized if selective
criteria for radiographic evaluation of the cervical spine were implemented.
If x-ray examination is required, three views of the cervical spine which
adequately view the cranio-cervical and cervico-thoracic junction and are
of good quality are sufficient for screening purposes. Swimmer's view and
supine oblique views may be necessary to adequately visualize the cervico-thoracic
junction in some individuals. Patients who complain of neck pain or dysesthesia
should have additional radiographic evaluation utilizing flexion/extension
films or more sophisticated technology. The patient who cannot communicate
or is obtunded, but has normal screening x-rays may be kept in a soft cervical
collar until alert, or have dynamic fluoroscopy of the neck performed by
an experienced examiner. The absolute risk of missing the presence of an
unstable cervical spine fracture when the screening examination is adequate
and interpreted as normal by an experienced examiner is unknown, but much
less than 1 %. Elderly patients sustain cervical spine fractures more commonly
with seemingly minor trauma. Degenerative changes of the spine complicate
the interpretation of x-rays performed to detect acute injury. The author
suggests the following algorithm as an appropriate approach to the patient
with a possible cervical spine injury, Figure 1. References 1. Alker GS, Oh YS, Leslie EV, et al. Postmortum radiology of head and
neck injuries in fatal accidents. Radiology 1975;114:611-617. 2. Buchoiz RW, Brukhead WZ, Graham W, et al. Occult cervical spine injuries
in fatal traffic accidents. J Trauma 1979;19:768-771. 3. Kip P, Hunter RE. Cervical spine fractures in Alpine skiers. Orthopedics
1995;18:737-41. 4. Oiler DW, Meredith JW, Rutiedge R, et al. The relationship between
face or skull fractures and cervical spine and spinal cord injuries: a review
of 1 3,834 patients. Accident Analysis & Prevention 1992;24:187-192, 5. O'Malley KF, Ross SE. The incidence of injury to the cervical spine
in patients with craniocerebral injury. J Trauma 1981;28:1476-1478. 6. Fisher RP. Cervical radiographic evaluation of alert patients following
blunt trauma. Ann Emerg Med 1984;13:905-907. 7. Jacobs LM, Schwartz R. Prospective analysis of acute cervical spine
injury: a methodology to predict injury. Ann Emerg Med 1986; 15:44-49. 8. Cadoux CG, White DJ, Hedberg MC. High yield roentgenographic criteria
for cervical spine injury. Ann Emerg Med 1987; 16:738-742. 9. Andrew CT, Galucci JG, Brown AS, Barot LR. Is routine cervical spine
radiographic evaluation indicated in patients with mandibular fractures?
Am Surg 1992;58:369-372. 1 0. Frye G, Wolf e T, Knopp R, Lesperance R, Williams J. lntracranial
hemorrhage as a predictor of occult cervical spine fracture. Ann Emerg Med
1994;23:797-80 1. 1 1. Williams J, Jehie D, Cottington E, Shufflebarger C. Head, facial
and clavicular trauma as a predictor of cervical-spine injury. Ann Emerg
Med 1992;21:719-722. 12, Ross SE, Schwab CW, David ET, Delong WG, Born CT. Clearing the cervical
spine: Initial radiographic evaluation. J Trauma 1987;27:1055-1060. 1 3. Hoffman JR, Schringer DL, Mower W, Luo JS, Zucker M. Low-risk criteria
for cervical-spine radiography in blunt trauma: a prospective study. Ann
Emerg Med 1992;21:1454-1460. 14. Hills MW, Deane SA. Head injury and facial injury: Is there an increased
risk of cervical spine injury? J Trauma 1993;34:549-554. 1 5. Maull KI, Sachatello CR. Avoiding pitfalls in resuscitation: The
painless cervical fracture. South Med J 1977;70:477-478. 1 6. Webb KJ, Broughton RBJ, McSweeney T, Park WM. Hidden flexion injury
of the cervical spine. J.B.Jt.S. 1976;58B:322-327. 1 7. Thambyrajah K. Fractures of the cervical spine with minimal or no
symptoms. Med J Malaysia 1972;26:244-249. C-spine Bell 9 18. Bresier MJ, Rich GH. Occult cervical spine fracture in an ambulatory
patient. Ann Emerg Med 1982; 11 :440-442. 19. Haines JD. Postgrad Med 1986;80:70-71. 20. Gattrell CB. "Asymptomatic' cervical injuries: a myth? Am J
Emerg Med 1985;3:263-264. 21. Sweeney JF, Rosemurgy AS, Gill S, Aibrink MH. Is the cervical spine
clear? Undetected cervical fractures diagnosed only at autopsy. Ann Emerg
Med 1992;21: 1288-90. 22. Rosa L. Missed fractures of the cervical spine. Milit Med 1989;154:39-41. 23. Mckee, TR, Tinkoff F, Rhodes M. Asymptomatic occult cervical spine
fracture: case report and review of the literature. J Trauma 1990;30:623-626 24. Roth BJ, Martin RR, Foley K, Barcia PJ, Kennedy P. Roentgenographic
evaluation of the cervical spine. A selective approach. Arch Surg 1994:129:643-645. 25. Roberge RJ, Wears RC, Kelly M, Evans TC, Kenny MA, Daffner RD, Kremen
R, Murray K, Cottington EC. Selective application of cervical spine radiography
in alert victims of blunt trauma: a prospective study. J Trauma 1988;28:784-788. 26. Ringenberg BJ, Fisher AK, Urdaneta LF. Rational ordering of cervical
spine radiographs following trauma. Ann Emerg Med 1988; 17:792-792. 27. Gbaandor GBM, Fruin AH, Taylon C. Role of routine emergency cervical
radiography in head trauma. Am J Surg 1986; 152:643-648. 28. Kreipke DL, Gillespie KR, McCarthy MC, Mail JT, Lappas JC, Broadie
TA. Reliability of indications for cervical spine films in trauma patients.
J Trauma 1989;29:1438-1439. 29. Mower WR, HoffmanJR, Schringer DL. The feasibility of selective radiography
in patients with trauma-induced neck pain. Ann Emerg Med 1990; 19:1220-122
1. 30. Neifield Gi, Keene JG, Hevesy G, et al. Cervical injury in head trauma,
J Emerg Med 1 988;6:203-207. 31. Vandemark RM. Radiology of the cervical spine in trauma patients:
Practice pitfalls and recommendations for improving efficiency and communication.
AJR. Am J Roentg 1990;1 55:465-472. 32. Laham JL, Cotcamp DH, Gibbons PA, Kahana MD, Crone KR. Isolated head
injuries versus multiple trauma in pediatric patients: do the same indications
for cervical spine evaluation apply? Ped Neurosurg 1994;21:221-226. 33. Spivka JM, Weiss MA, Cotler JM, Call M. Cervical spine injuries in
patients 65 and older. Spine 1994;1 9:2302-2306. 34. Lieberman IH, Webb JK, Cervical spine injuries in the elderly. J.B.Jt.S.
1994;76:877-881. 35. The American College of Radiology Task Force on Appropriateness Criteria.
"Appropriateness Criteria for lmaging and Treatment Decisions. 1995. 36. Mirvis SE, Diaconis JN, Chirico PA. Protocol-driven radiologic evaluation
of suspected cervical spine C-spine Bell 10 injury: Efficacy study. Radiology
1989:170: 831. 37. Woodring JH, Lee C. Limitations of cervical radiography in the evaluation
of acute cervical trauma. J Trauma 1993;34:32-39. 38. McDonald RL, Schwartz ML, Mirich D, Sharkey PW, Nelson WR. Diagnosis
of cervical spine injury in motor vehicle crash victims: How many x-rays
are enough? J Trauma 1990;30:392-397. 39. Shaffer MA, Doris PE. Limitations of the cross table lateral view
in detecting cervical spine injuries: A retrospective analysis. Ann Emerg
Med 1 983; 10:508-51 3. 40. Wales LR, Knopp RK, Morishima MS. Recommendations for evaluation
of the acutely injured cervical spine: A clinical radiologic algorithm.
Ann Emerg Med 1984;9:422-428. 41. Freemyer B, Knopp R, Piche J. Comparison of five-view and three-view
spine series in the evaluation of patients with cervical trauma. Ann Emerg
Med 1989; 18:818-821. 42. Turetsky DB, Vines FS, Clayman DA, Northup HM. Technique and use
of supine oblique views in acute cervical spine trauma. Ann Emerg Med 1993;22:685-689. 43. Daffner RH. Evaluation of cervical vertebral injuries. Semin Roentgen1992;27:239-253. 44. Blacksin MF, Lee HJ. Frequency and significance of fractures of the
upper cervical spine detected by CT in patients with severe neck trauma.
AJR. Am J Roentg 1995;165:1201-1204. 45. Link TM, Schuierer G, Hufendiek A, Horch C, Peters PE. Substantial
head trauma: Value of routine CT Examination of the cervicocranium. Radiology
1995; 196:741-745. 46. Woodring JH, Lee C. The role and limitations of computed tomographic
scanning in the evaluation of cervical trauma. J Trauma 1992;33:698-708. 47. Davis JW, Parks SN, Detiefs, CL, Williams GG, Williams JL, Smith
RW. Clearing the cervical spine in obtunded patients: The use of dynamic
fluoroscopy. J Trauma 1995;39:435-438. 48. Bell, RM. Unpublished data. 49. Davis JW, Phreaner DL, Hoyt DB, Mackersie RC. The etiology of missed
cervical spine injuries. J Trauma 1993;34:342-346. 50. Daffner RM, Deeb ZL, Rothfus, WD. "Fingerprints" of vertebral
trauma-unifying concept based on mechanisms. Skeletal Radiol 1982;15:518-525. 5 1. DeBehnke KJ, Havel CJ. Utility of prevertebral soft tissue measurements
in identifying patients with cervical spine fractures. Ann Emerg Med 1994;26:111-1124. 52. Tehranzadeh JH, Bonk RT, Ansari A, Mesgarzadeh M. Efficacy of limited
CT for nonvisualized lower cervical spine in patients with blunt trauma.
Skeletal Radiol 1994;23:349-352.
|
Back to top