Imaging for evaluation of suspected cervical spine trauma: a 2-year analysis

Ultra-low-dose CT versus radiographs for minor spine and pelvis trauma: a Bayesian analysis of accuracy

OBJECTIVES

To compare diagnosis performance and effective dose of ultra-low-dose CT (ULD CT) versus radiographs in suspected spinal or pelvic ring or hip fracture for minor trauma.

METHODS

ULD CT, in addition to radiography, was prospectively performed in consecutive patients admitted to the emergency department for minor traumas, during working hours over 2 months. Presence of a recent fracture was assessed by two blind radiologists independently. Sensitivities and specificities were estimated using the best valuable comparator (BVC) as a reference and using a latent class model in Bayesian inference (BLCM). Dosimetric indicators were recorded and effective doses (E) were calculated using conversion coefficient.

RESULTS

Eighty areas were analyzed in 69 patients, including 22 dorsal spine, 28 lumbar spine, and 30 pelvic ring/hip. Thirty-six fractures (45%) were observed. Applying the BVC method, depending on location, ULD CT sensitivity was 80 to 100% for reader 1 and 85 to 100% for reader 2, whereas radiographic sensitivity was 60 to 85% for reader 1 and 50 to 92% for reader 2. With BLCM approach for reader 2, ULD CT sensitivity for all locations/dorsal spine/lumbar spine and pelvic ring-hip was 87.1/75.9/84.2/76.9% respectively. Corresponding radiograph sensitivity was 73.8, 54.8, 80.4, and 68.7%. Effective doses of ULD CT were similar to radiographs for dorsal and hip locations whereas for lumbar spine, ULD CT effective dose was 1.83 ± 0.59 mSv compared with 0.96 ± 0.59 mSv (p < 0.001).

CONCLUSION

Sensitivity for fracture detection was higher for ULD CT compared with radiographs with an effective dose comparable to radiographs.

KEY POINTS

• Ultra-low-dose spine and pelvis CT demonstrates better fracture detection when compared with radiographs. • The effective dose of ultra-low-dose spine and pelvis CT scan and radiographs is comparable. • Replacement of radiographs by ULD CT in daily practice for trauma patients is an option to consider and should be evaluated by a randomized trial.

Primary Imaging Test for Suspected Traumatic Thoracolumbar Spine Injury: 2017 Guidelines by the Korean Society of Radiology and National Evidence-Based Healthcare Collaborating Agency

The Korean Society of Radiology and the National Evidence-based Healthcare Collaborating Agency developed a primary imaging test for suspected traumatic thoracolumbar spine injury. This guideline was developed using an adaptation process involving collaboration between the development committee and the working group. The development committee, consisting of research methodology experts, established the overall plan and provided support on research methodology. The working group, composed of radiologists with expertise in musculoskeletal imaging, wrote the recommendation. The guidelines recommend that thoracolumbar spine computed tomography without intravenous contrast enhancement be the first-line imaging modality for diagnosing traumatic thoracolumbar spine injury in adults.

Imaging investigations in Spine Trauma: The value of commonly used imaging modalities and emerging imaging modalities

Traumatic spine injuries can be devastating for patients affected and for health care professionals if preventable neurological deterioration occurs. This review discusses the imaging options for the diagnosis of spinal trauma. It lays out when imaging is appropriate and when it is not. It discusses strength and weakness of available imaging modalities. Advanced techniques for spinal injury imaging will be explored. The review concludes with a review of imaging protocols adjusted to clinical circumstances.

Management of acute traumatic spinal cord injuries

Acute traumatic spinal cord injury (SCI) is a devastating disease process affecting tens of thousands of people across the USA each year. Despite the increase in primary prevention measures, such as educational programs, motor vehicle speed limits, automobile running lights, and safety technology that includes automobile passive restraint systems and airbags, SCIs continue to carry substantial permanent morbidity and mortality. Medical measures implemented following the initial injury are designed to limit secondary insult to the spinal cord and to stabilize the spinal column in an attempt to decrease devastating sequelae. This chapter is an overview of the contemporary management of an acute traumatic SCI patient from the time of injury through the stay in the intensive care unit. We discuss initial triage, immobilization, and transportation of the patient by emergency medical services personnel to a definitive treatment facility. Upon arrival at the emergency department, we review initial trauma protocols and the evidence-based recommendations for radiographic evaluation of the patient's vertebral column. Finally, we outline closed cervical spine reduction and various aggressive medical therapies aimed at improving neurologic outcome.

[Imitation of an Anderson type II dens fracture by a motion artefact in computed tomography : Four case examples]

Computed tomography (CT) is the method of choice in the diagnosis and classification of odontoid fractures with a sensitivity of more than 99 % and a specificity almost equally as high. In this article we report on four cases where CT-generated motion artefacts exactly mimicked an Anderson type II fracture of the dens axis, initially leading to a wrong diagnosis. Although this seems to be a very rare event, these cases indicate that overlooked CT motion artefacts can lead to severe consequences and attention must be paid to the radiological signs outlined in this report.

Diagnostic Value of Serum Levels of GFAP, pNF-H, and NSE Compared With Clinical Findings in Severity Assessment of Human Traumatic Spinal Cord Injury

STUDY DESIGN

An analytical cohort study.

OBJECTIVE

This study aimed to evaluate severity of traumatic spinal cord injury (SCI) based on the serum levels of phosphorylated form of heavy subunit of neurofilament (pNF-H), neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP), which are axonal, neural cell body, and glial cell injury markers, respectively.

SUMMARY OF BACKGROUND DATA

Prior studies have reported elevated serum levels of pNF-H, NSE, and GFAP as biomarkers for the detection of traumatic SCI in animals. However, in this study, these biomarkers were studied in humans and with an extended level of timing.

METHODS

The study included 35 patients with SCI with a mean age of 36.5 years. All patients were evaluated using the American Spinal Injury Association Impairment Scale, followed by examinations including radiography and spinal computed tomography for determining the injury level. Serum levels of NSE, pNF-H, and GFAP were determined using enzyme-linked immunosorbent assay.

RESULTS

The mean serum level of GFAP was significantly higher in patients with SCI than in the control group. Mean serum levels of pNF-H and NSE were significantly higher during 24 and 48 hours after injury in patients with SCI than in the control group. The serum level of GFAP was appropriate for estimating the severity of SCI in the first 24 hours after injury.

CONCLUSION

Our findings suggest that increased serum levels of GFAP, NSE, and pNF-H can be used for the diagnosis and degree of SCI severity in trauma patients. During 48 hours after injury, estimation of serum levels of pNF-H, NSE, and GFAP, combined with neurological testing, could predict the presence of SCI and severity prior to spinal computed tomography and surgical or conservative interventions.

LEVEL OF EVIDENCE

2.

Cervical spine immobilization following blunt trauma: a systematic review of recent literature and proposed treatment algorithm

BACKGROUND

Management of the cervical spine following blunt trauma is commonplace. In 2013, the American Association of Neurological Surgeons (AANS) and the Congress of Neurological Surgeons (CNS) published practice guidelines drawn from evidence dating to 2011. Since then, further publications have emerged that are reviewed, and a simple management algorithm produced to assist practitioners in Australian trauma centres. These publications attempt to shed light on two controversial scenarios, those being the management of symptomatic patients with negative computed tomography (CT) and management of the obtunded patient.

METHODS

The search strategy mirrored that of the AANS/CNS guidelines. A search of the National Library of Medicine (PubMed) database for manuscripts published between January 2011 and October 2014 was conducted. One reviewer extracted data from studies assessing the performance of various imaging modalities in identifying traumatic cervical spine injuries. In clinical scenarios where little evidence has emerged since the AANS/CNS guidelines, key manuscripts published prior to 2011 were identified from bibliographies.

RESULTS

Awake, asymptomatic patients may be 'cleared' without further imaging. Awake, symptomatic patients without pathology on CT and without neurological deficit can safely be 'cleared' without magnetic resonance imaging. There is no longer a role for flexion-extension films. In the obtunded patient, findings remain conflicting.

CONCLUSION

Several of these findings represent a departure from previous practices, including clearance of patients with non-neurological symptoms on the basis of CT and the exclusion of flexion-extension film in detecting injury. Management of the obtunded patient remains controversial.

X-ray population exposure from projection radiology and computed tomography in Emilia-Romagna from 2001 to 2010: comparison of ICRP 60 and ICRP 103 weighting factors

PURPOSE

This paper shows the trends from 2001 to 2010 of per caput and collective effective dose (S) to the Emilia-Romagna population due to radiation exposure from projection radiology (PR) and computed tomography (CT), calculated according to both ICRP60 and ICRP103 tissue weighting factors.

MATERIALS AND METHODS

The frequency of examinations and dose calculations were based on data provided directly by Emilia-Romagna Health Trusts. In particular, effective doses were evaluated using the tissue weighting (w T) factors reported both in ICRP60 (w T,60) and in ICRP103 (w T,103).

RESULTS

A decrease in the frequency of PR skull examinations and an increase in the frequency of mammography, CT of the abdomen, chest, and head-neck were found during the decade. In 2010, the PR/CT procedures contributed 75.4 %/24.6 % to examination frequency and approximately 10 %/90 % to dose; S was 6,169.2 man Sv when w T,60 was used and 5,855.1-6,665.5 man Sv when w T,103 in two different mathematical models was utilised.

CONCLUSIONS

Dose estimates pre- and post-ICRP103 must be compared carefully, because changes due to different radiological practices could be confused with changes due to the use of different w T's. In general, dose evaluations with the use of w T,60 until 2007 and w T,103 from 2008 seem to be consistent and coherent.

Cervical spine clearance in the traumatically injured patient: is multidetector CT scanning sufficient alone? Clinical article

OBJECT

Clearance of the cervical spine in patients who have sustained trauma remains a contentious issue. Clinical examination alone is sufficient in neurologically intact patients without neck pain. Patients with neck pain or those with altered mental status or a depressed level of consciousness require further radiographic evaluation. However, no consensus exists as to the appropriate imaging modality. Some advocate multidetector CT (MDCT) scanning alone, but this has been criticized because MDCT is not sensitive in detecting ligamentous injuries that can often only be identified on MRI.

METHODS

Patients were identified retrospectively from a prospectively maintained database at a Level I trauma center. All patients admitted between January 2004 and June 2011 who had a cervical MDCT scan interpreted by a board-certified radiologist as being without evidence of acute traumatic injury and who also had a cervical MRI study obtained during the same hospital admission were included. Data collected included patient demographics, mechanism of injury, Glasgow Coma Scale score at the time of MRI, the indication for and findings on MRI, and the number, type, and indication for cervical spine procedures.

RESULTS

A total of 1004 patients were reviewed, of whom 614 were male, with an overall mean age of 47 years. The indication for MRI was neck pain in 662 patients, altered mental status in 467, and neurological signs or symptoms in 157. The MRI studies were interpreted as normal in 645 patients, evidencing ligamentous injury alone in 125, and showing nonspecific degenerative changes in the remaining patients. Of the 125 patients with ligamentous injuries, 66 (52.8%) had documentation of clearance (29 clinical, 37 with flexion-extension radiographs). Another 32 patients were presumed to be self-cleared, bringing the follow-up rate to 82% (98 of 119). Five patients died prior to clearance, and 1 patient was transferred to another facility prior to clearance. Based on these data, the 95% confidence interval for the assertion that clinically irrelevant ligamentous injury in the face of normal MDCT is 97%-100%. No patient with ligamentous injury on MRI was documented to require a surgical procedure or halo orthosis for instability. Thirty-nine patients ultimately underwent cervical surgical procedures (29 anterior and 10 posterior; 5 delayed) for central cord syndrome (21), quadriparesis (9), or discogenic radicular pain (9). None had an unstable spine.

CONCLUSIONS

In this study population, MRI did not add any additional information beyond MDCT in identifying unstable cervical spine injuries. Magnetic resonance imaging frequently detected ligamentous injuries, none of which were found to be unstable at the time of detection, during the course of admission, or on follow-up. Magnetic resonance imaging provided beneficial clinical information and guided surgical procedures in patients with neurological deficits or radicular pain. An MDCT study with sagittal and coronal reconstructions negative for acute injury in patients without an abnormal motor examination may be sufficient alone for clearance.

Does the ratio and thickness of prevertebral soft tissue provide benefit in blunt cervical spine injury?

PURPOSE

Although many reports advocate computed tomography (CT) as the initial surveillance tool for occult cervical spine injury (CSI) at the emergency department (ED), the role of a lateral cervical spine radiograph (LCSX) has still not been replaced. We hypothesized that the increased width of the prevertebral soft tissue on an LCSX provides helpful information for selecting the high-risk patients who need to be evaluated with more accurate diagnostic tools.

METHODS

This was a retrospective and consecutive series of injured patients requiring cervical spine evaluation who were first imaged with three-view plain films at the ED. The prevertebral soft tissue thickness (PVST) and ratio of prevertebral soft tissue thickness to the cervical vertebrae diameter (PVST ratio) were calculated on the LCSX. Suspicion of CSI was confirmed by either CT or magnetic resonance imaging (MRI) scans.

RESULTS

A total of 826 adult trauma patients requiring cervical spine evaluation were enrolled. The C3 PVST and PVST ratio were significantly different between patients with or without upper cervical area injury (UCAI, 8.64 vs. 5.49 mm, and 0.394 vs. 0.276, respectively), and, likewise, the C6 PVST and PVST ratio for patients with or without lower cervical area injury (LCAI, 16.89 vs. 14.66 mm, and 0.784 vs. 0.749, respectively). The specificity was greater than 90 % in predicting UCAI and LCAI when combining these two parameters.

CONCLUSIONS

This method maximizes the usefulness of LCSX during the initial assessment of a conscious patient with blunt head and neck injury, especially for the identification of high-risk patients requiring prompt CT or MRI; on the other hand, it prevents the overuse of these high-cost imaging studies as initial diagnostic tools.

Motion Induced Artifact Mimicking Cervical Dens Fracture on the CT Scan: A Case Report

The diagnostic performance of helical computed tomography (CT) is excellent. However, some artifacts have been reported, such as motion, beam hardening and scatter artifacts. We herein report a case of motion-induced artifact mimicking cervical dens fracture. A 60-year-old man was involved in a motorcycle accident that resulted in cervical spinal cord injury and quadri plegia. Reconstructed CT images of the cervical spine showed a dens fracture. We assessed axial CT in detail, and motion artifact was detected.

Comparative effectiveness of using computed tomography alone to exclude cervical spine injuries in obtunded or intubated patients: meta-analysis of 14,327 patients with blunt trauma

Object

The current standard of practice for clearance of the cervical spine in obtunded patients suffering blunt trauma is to use CT and an adjuvant imaging modality (such as MR imaging). The objective of this study was to determine the comparative effectiveness of multislice helical CT alone to diagnose acute unstable cervical spine injury following blunt trauma.

Methods

The authors performed a meta-analysis of studies comparing modern CT with adjunctive imaging modalities and required that studies present acute traumatic findings as well as treatment for unstable injuries. Study quality, population characteristics, diagnostic protocols, and outcome data were extracted. Positive disease status included all injuries necessitating surgical or orthotic stabilization identified on imaging and/or clinical follow-up.

Results

Seventeen studies encompassing 14,327 patients met the inclusion criteria. Overall, the sensitivity and specificity for modern CT were both > 99.9% (95% CI 0.99–1.00 and 0.99–1.00, respectively). The negative likelihood ratio of an unstable cervical injury after a CT scan negative for acute injury was < 0.001 (95% CI 0.00–0.01), while the negative predictive value of a normal CT scan was 100% (95% CI 0.96–1.00). Global severity of injury, CT slice thickness, and study quality did not significantly affect accuracy estimates.

Conclusions

Modern CT alone is sufficient to detect unstable cervical spine injuries in trauma patients. Adjuvant imaging is unnecessary when the CT scan is negative for acute injury. Results of this meta-analysis strongly show that the cervical collar may be removed from obtunded or intubated trauma patients if a modern CT scan is negative for acute injury.

Computed tomographic artifact suggesting cervical facet subluxation

STUDY DESIGN

A case report with review of the literature on the cause of computed tomographic (CT) artifacts and recommendations for identification of such artifacts.

OBJECTIVE

To describe the presentation of a patient with a CT scan suggesting a cervical facet dislocation that ultimately proved to be artifactual.

SUMMARY OF BACKGROUND DATA

CT scanning is routinely used in the detection of cervical spine injuries. This technique has a reported sensitivity of 98%, although specificity has proved more difficult to estimate. CT artifacts such as the case reported here is a significant cause of a decrease in specificity for this technique.

METHODS

A 30-year-old woman with a history of a cervical fracture developed severe neck pain without neurologic deficit after trauma to the back of her neck. CT scans were obtained and reviewed at a local secondary level hospital. A cervical fracture dislocation was diagnosed and cervical spinal injury protocols were initiated and the patient transferred to authors', tertiary level institution for surgical management. A repeat CT scan showed her cervical spine to be in normal alignment.

RESULTS

A movement artifact in the patient's original CT scans was misinterpreted as a unilateral facet fracture subluxation at C5-C6. There are two clues that in hindsight indicate that this finding was artifactual; an ill-defined tracheal margin in contrast with the sharply defined margin above and below the level of the artifact and a double bone margin seen on axial sections at the level of the artifact.

CONCLUSION

Motion artifacts are an important cause in the reduction in specificity of CT scans and can be easily missed. It is important to be aware of the indicators of motion artifacts to reduce the risk of unnecessary treatments.

Diagnosing cervical spine instability: role of the post-computed tomography scan out-of-collar lateral radiograph

BACKGROUND

Cervical spine injuries may have devastating neurological consequences, which makes accurate diagnosis of injury a key part of the trauma evaluation. Imaging plays a significant role in making the diagnosis and guiding management. Current American College of Radiology Appropriateness Criteria guidelines recommend computed tomography (CT) of the cervical spine with multi-planar reformats as the highest-rated imaging examination for patients meeting clinical criteria, without subsequent need for further imaging with a negative scan in a neurologically intact and non-obtunded patient. Although CT is fast and accurate for evaluation of bony injury, it may overlook ligamentous injury.

OBJECTIVE AND CASE REPORT

We report a case in which ligamentous instability was demonstrated as subluxation with an out-of-collar lateral radiograph after a CT scan showed no subluxation or fracture in a patient without neurological deficits. Our Radiology Department routinely performs an out-of-collar lateral radiograph after a negative CT scan, and this case suggests that there may be an important role for this practice.

CONCLUSION

Magnetic resonance is the optimal study for soft tissue and ligamentous evaluation; however, a simple lateral out-of-collar radiograph after CT clearance, in an otherwise neurologically intact and non-obtunded patient, may be a quick and cost-effective means to assess for instability of the cervical spine.

Clearance of the cervical spine in clinically unevaluable trauma patients

STUDY DESIGN

Meta-analytic costeffectiveness analysis.

OBJECTIVE

Our goal was to compare the results of different management strategies for trauma patients in whom the cervical spine was not clinically evaluable due to impaired consciousness, endotracheal intubation, or painful distracting injuries.

SUMMARY OF BACKGROUND DATA

We performed a structured literature review related to cervical spine trauma, radiographic clearance techniques (plain radiography, flexion/extension, CT, and MRI), and complications associated with semirigid collar use.

METHODS

Meta-analytic techniques were used to pool data from multiple sources to calculate pooled mean estimates of sensitivities and specificities of imaging techniques for cervical spinal clearance, rates of complications from various clearance strategies and from empirical use of semirigid collars. A decision analysis model was used to compare outcomes and costs among these strategies.

RESULTS

Slightly more than 7.5% of patients who are clinically unevaluable have cervical spine injuries, and 42% of these injuries are associated with spinal instability. Sensitivity of plain radiography or fluoroscopy for spinal clearance was 57% (95% CI: 57%-60%). Sensitivities for CT and MRI alone were 83% (82%-84%) and 87% (84%-89%), respectively. Complications associated with collar use ranged from 1.3% (2 days) to 7.1% (10 days) but were usually minor and short-lived. Quadriplegia resulting from spinal instability missed by a clearance test had enormous impacts on longevity, quality of life, and costs. These impacts overshadowed the effects of prolonged collar application, even when the incidence of quadriplegia was extremely low.

CONCLUSION

As currently used, neuroimaging studies for cervical spinal clearance in clinically unevaluable patients are not cost-effective compared with empirical immobilization in a semirigid collar.

Misdiagnosed bilateral C5-C6 dislocation causing cervical spine instability: a case report

INTRODUCTION

The diagnosis of cervical spine injuries remains a significant problem in many blunt trauma patients. Correct and early diagnosis of these injuries is imperative as delayed or missed diagnoses result in increased morbidity and mortality.

CASE PRESENTATION

A 57-year-old Caucasian woman presented with a misdiagnosed bilateral C5-C6 dislocation one month after a fall and head injury, without clearance of the cervical spine in her previous visits to two physicians and having already started physiotherapy sessions, despite the presence of pain in the clinical examination. Dislocation was treated with open reduction and spinal fusion with posterior instrumentation 4 weeks post-trauma.

CONCLUSIONS

Every physician should be highly suspicious of cervical spine injury in blunt trauma patients with positive clinical examination and include radiologic studies in his screening modality. Physiotherapy sessions should under no circumstances be started in the presence of underlying spine injury.

Role of multidetector computed tomography in the assessment of cervical spine trauma

Clearing the cervical spine has relied on individual and center-based experience. Not long ago, the screening modality of choice was radiography. The evidence now clearly supports multidetector computed tomography as the modality of choice for evaluating cervical spine trauma because of its higher accuracy and efficiency compared to radiography. Furthermore, clinical criteria have been validated to assess for cervical spine injuries and determine the need for imaging evaluation based on patient risk. Once imaging is deemed necessary to exclude cervical spine injury based on clinical predictors, multidetector computed tomography becomes the accepted modality of choice, providing accurate and rapid assessment and improving the understanding of injury patterns and stability determinants.

Exclusion of cervical spine instability in patients with blunt trauma with normal multidetector CT (MDCT) and radiography

The objective of the study was to determine if negative multidetector computed tomography (MDCT) and lateral radiography of the cervical spine effectively excludes patients with unstable cervical spine injuries. Over a period of 40 months, 6558 people were admitted to our trauma service with blunt injury and 447 (6.8%) were found to have cervical fractures. Fractures were identified by CT and/or lateral radiography. In order to rule out clinically significant instability in the absence of fracture, we identified nine patients who required any type of stabilization of the cervical spine including anterior fusion, posterior fusion and external orthosis. These patients also underwent MR of the cervical spine. Radiography, CT, and MR images and reports of these nine patients were reviewed. Nine patients without a fracture required cervical stabilization. These patients had the following abnormalities: disc herniation with canal stenosis in three, unilateral jumped facet in three, and various other soft tissue abnormalities in three, all of which were evident on CT or radiography. All nine patients had evidence for cervical spine injury or instability by MDCT. Normal MDCT and radiography appears adequate to 'clear' the cervical spine. We recommend that patients requiring cervical spine clearance undergo a complete MDCT and lateral radiograph of the cervical spine. If these studies are entirely normal, then the cervical spine may be cleared. If any abnormalities, including disc herniation, soft tissue swelling and bony malalignments are noted by radiography and/or MDCT, further studies, including MR, are indicated prior to clearance of the cervical spine.

Utility of helical computed tomography in differentiating unilateral and bilateral facet dislocations

OBJECTIVE

Diagnosis of cervical facet dislocation is difficult when relying on plain radiographs alone. This study evaluates the interobserver reliability of helical computed tomography (CT) in the assessment of cervical translational injuries, correlates the radiographic diagnosis with intraoperative observation, and examines the role of neurologic injury in the evaluation and diagnosis of these injuries.

METHODS

Clinical histories and radiographic studies of 10 patients with cervical facet dislocations were presented to 25 surgeons. Participants classified cases as unilateral or bilateral facet dislocations after reviewing selected axial CT slices and sagittal reconstructions. Surgeons' interpretations were compared with intraoperative diagnosis. Participants interpreted the same radiographic studies with 3 different clinical scenarios: neurologically intact, incomplete, and complete spinal cord injury. Vertebral body translation from midsagittal CT was evaluated to confirm whether all unilateral facet dislocations had <25% translation.

RESULTS

Interrater kappa coefficient showed moderate agreement between observers in classifying injuries as unilateral or bilateral (kappa: 0.54-0.58), regardless of neurologic status. Percent agreement among observers varied from 50% to 100% for each individual case. Agreement was statistically higher for bilateral facet dislocation (85%) than for unilateral dislocations (78%), with 1 unilateral fracture showing nearly 50% translation on a midsagittal image.

CONCLUSIONS

The addition of helical CT to reconstruction enables spine surgeons to more reliably distinguish bilateral from unilateral cervical facet dislocations. Despite frequent occurrence of these injuries and presumed agreement on injury description, agreement may be improved by a more precise definition of facet dislocations and subluxations and thorough review of all imaging studies.

Normal thickness and appearance of the prevertebral soft tissues on multidetector CT

BACKGROUND AND PURPOSE

Analysis of the prevertebral soft tissue (PVST) is helpful in detecting osseous and ligamentous injuries of the cervical spine. Because the standard of care has shifted from radiographs to multidetector CT (MDCT), a re-examination of the PVST on MDCT images is needed to establish normal values for thickness appropriate for this imaging technique.

MATERIALS AND METHODS

Thickness of the PVST was measured in 192 patients undergoing screening cervical spine MDCT with multiplanar reconstructions as part of a trauma protocol. Patients included in the study were not intubated, had an immobilized cervical spine, had normal findings on cervical spine CT, and did not have a diagnosis of osseous or soft-tissue cervical injury. Exclusion criteria included patients with a congenital or acquired (nondegenerative) abnormality of the cervical spine or PVST.

RESULTS

The upper limits of normal for the thickness of the PVST were 8.5 mm at C1, 6 mm at C2, 7 mm at C3, 18 mm at C6, and 18 mm at C7. The upper limit of normal was not determined for C4 and C5 levels due to variable position of the esophagus and larynx. The smallest variability and calculated SDs were found at C2 and C3.

CONCLUSIONS

The thickness of the PVST is important in the detection of underlying injuries to the cervical spine. We propose the obtained values as the upper limits of normal for PVST thickness on MDCT images in the adult population.

Prevalence of cervical spinal injury in trauma

Object

Diagnosis of cervical spinal injury (CSI) is an essential aspect of the trauma evaluation. This task is especially difficult in patients who are not clinically able to be evaluated (unevaluable) because of distracting painful injuries, intoxication, or concomitant head injury. For this population, the appropriate use of advanced imaging techniques for cervical spinal clearance remains undetermined. This study was undertaken to estimate the prevalence of unstable CSI, particularly among patients in whom clinical evaluation is impossible or unreliable.

Methods

Estimates of the prevalence of CSI in populations consisting of all trauma patients, alert patients only, and clinically unevaluable patients only were determined by variance-weighted pooling of data from 65 publications (281,864 patients) that met criteria for review.

Results

The overall prevalence of CSI among all trauma patients was 3.7%. The prevalence of CSI in alert patients was 2.8%, whereas unevaluable patients were at increased risk of CSI with a prevalence of 7.7% (p = 0.007). Overall, 41.9% of all CSI cases were considered to exhibit instability.

Conclusions

Trauma patients who are clinically unevaluable have a higher prevalence of CSI than alert patients. Knowledge of the prevalence and risk of such injuries may help establish an evidence-based approach to the detection and management of clinically occult CSI.

An evidenced-based approach to radiographic assessment of cervical spine injuries in the emergency department

The modern approach to suspected cervical spine injuries is highly dependent on appropriate utilization of radiographic studies. Clinical decision rules have been developed for determination of those most likely to benefit from plain film studies, but there is confusion regarding those who should undergo computed tomography (CT) scanning. This case-based review highlights current available evidence and provides a framework to guide emergency medicine providers in the treatment of patients with trauma to the cervical spine.

Advanced trauma life support, 8th edition, the evidence for change

The American College of Surgeons Committee on Trauma's Advanced Trauma Life Support Course is currently taught in 50 countries. The 8th edition has been revised following broad input by the International ATLS subcommittee. Graded levels of evidence were used to evaluate and approve changes to the course content. New materials related to principles of disaster management have been added. ATLS is a common language teaching one safe way of initial trauma assessment and management.

Is the lateral cervical spine x-ray obsolete during the initial evaluation of patients with acute trauma?

BACKGROUND

Clearing the cervical spine is a vital part of the treatment of trauma patients, and the failure to accurately diagnose an injury to the cervical spine can result in paralysis and even death. For decades, plain film imaging, primarily LCSX, was the standard imaging method used to initially evaluate the cervical spine, with CSCT used as an adjunct. With advancements in CSCT over the past decade, it is generally accepted that CSCT should be used as the screening method for clearance of the cervical spine in patients with trauma. In this study our goal was to determine whether lateral cervical spine radiographs (LCSX) are warranted in the initial evaluation of trauma patients or whether they should be eliminated completely in favor of CSCT scans as the initial method of evaluating the cervical spine in trauma patients.

METHODS

This is a retrospective study using a prospectively maintained computerized database of all trauma admissions to a level II American College of Surgeons verified trauma center. Patients who were identified to have both LCSX and CSCT on admission were analyzed. Radiology readings (LCSX and CSCT) of the selected patients were reviewed and comparisons were made to determine the number of patients for which the LCSX was inconclusive or unsatisfactory. It was also determined whether, in selected cases, there were injuries or abnormal findings that were detected in one imaging modality but were not detected in the other.

RESULTS

A total of 895 trauma admissions were reviewed; 177 had both LCSX and CSCT. The radiological results of the 177 patients were analyzed. Fifty-one (28%) patients were determined to have inadequate LCSX in which further scans were required for diagnosis or clearance of the cervical spine. Thirty-six (20%) patients had fractures that were undetected by LCSX.

CONCLUSIONS

Our research supports previous studies demonstrating the greater accuracy of CT in evaluating the cervical spine in acute trauma patients. Moreover, with spiral CT scanning, the length of time required to obtain images has been eliminated as an issue. We conclude that LCSX should be eliminated from trauma protocols and that CSCT should be the sole imaging modality used in the initial evaluation of the cervical spine after trauma.

Computed tomography reconstruction artifact suggesting cervical spine subluxation

Use of computed tomography (CT) imaging for evaluation of the cervical spine following blunt trauma is both an efficient and reliable method for detecting injury. As a result, many trauma centers and emergency departments rely exclusively on CT scans to acutely clear the cervical spine of injury. Although quite sensitive for detecting bone injury, CT may be associated with a low sensitivity for detecting herniated discs, injured soft tissue or ligaments, and dynamic instability. In addition, CT-generated artifact may obscure pathological findings. In this case report, we describe the course of a patient whose CT scan harbored CT-generated artifact that suggested traumatic subluxation of the cervical spine. Clinicians should be aware of such artifact and how to recognize it when basing clinical management on such studies.