Best Practice in Diagnostic Imaging after Blunt Force Trauma Injury to the Cervical Spine: A Systematic Review

IntroductionThe aim of this study was to investigate best practice in evidence-based clinical examinations to determine the diagnostic efficacy of plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI) of a cervical spine injury after blunt force trauma.MethodsA systematic review of recent literature was performed, with the intention of analysing only original research articles focusing on at least two imaging modalities or clinical decision guidelines in relation to blunt force trauma injuries involving the cervical spine. The search used the following databases: ProQuest Central, ScienceDirect, and Scopus. A total of 18 studies were identified as suitable for review; these were further supported by relevant secondary studies.ResultsIt was found that the National Emergency X-Radiology Utilization Study and the Canadian C-Spine Rule are both highly sensitive methods for screening patients after cervical spine injuries. CT was shown to have a higher validity than plain radiography and MRI for the detection of a bony cervical spine injury. MRI is recommended for obtunded or unevaluable patients with suspected neurologic deficit.ConclusionsOverall, the literature appears to suggest that individuals with a suspected high risk of injury after examination using clinical decision rules should undergo a cervical CT examination. For patients who are found to have a low risk of injury after clinical decision guidelines, good-quality plain radiography is recommended as sufficient.     

Are computed tomography scans adequate in assessing cervical spine pain following blunt trauma?

Good quality three-view radiographs (anteroposterior, lateral, and open-mouth/odontoid) of the cervical spine exclude most unstable injuries, with sensitivity as high as 92% in adults and 94% in children. The diagnostic performance of helical computed tomography (CT) scanners may be even greater, with reported sensitivity as high as 99% and specificity 93%. Missed injuries are usually ligamentous, and may only be detected with magnetic resonance imaging (MRI) or dynamic plain radiographs. With improvements in the accessibility of advanced imaging (helical CT and MRI) and with improvements in the resolution of such imaging, dynamic screening is now used less commonly to screen for unstable injuries. This case involves a patient with an unstable cervical spine injury whose cervical subluxation was only detected following use of dynamic radiographs, despite a prior investigation with helical CT. In this way, the use of dynamic radiographs following blunt cervical trauma should be considered an effective tool for managing acute cervical spine injury in the awake, alert, and neurologically intact patient with neck pain.     

Cervical Spine Injuries in Children, Part I: Mechanism of Injury, Clinical Presentation, and Imaging

Background: Cervical spine injuries are difficult to diagnose in children. They tend to occur in different locations than in adults, and they are more difficult to identify based on history or physical examination. As a result, children are often subjected to radiographic examinations to rule out cervical spine injury. Objectives: This two-part series will review the classic cervical spine injuries encountered in children based on age and presentation. Part I will discuss the mechanisms of injury, clinical presentations, and the use of different imaging modalities, including X-ray studies and computed tomography (CT). Part II discusses management of these injuries and special considerations, including the role of magnetic resonance imaging, as well as injuries unique to children. Discussion: Although X-ray studies have relatively low risks associated with their use, they do not identify all injuries. In contrast, CT has higher sensitivity but has greater radiation, and its use is more appropriate in children over 8 years of age. Conclusion: With knowledge of cervical spine anatomy and the characteristic injuries seen at different stages of development, emergency physicians can make informed decisions about the appropriate modalities for diagnosis of pediatric cervical spine injuries.     

Cervical Spine Injuries in Children, Part II: Management and Special Considerations

Background: The diagnosis and management of cervical spine injury is more complex in children than in adults. Objectives: Part I of this series stressed the importance of tailoring the evaluation of cervical spine injuries based on age, mechanism of injury, and physical examination findings. Part II will discuss the role of magnetic resonance imaging (MRI) as well as the management of pediatric cervical spine injuries in the emergency department. Discussion: Children have several common variations in their anatomy, such as pseudosubluxation of C2–C3, widening of the atlantodens interval, and ossification centers, that can appear concerning on imaging but are normal. Physicians should be alert for signs or symptoms of atlantorotary subluxation and spinal cord injury without radiologic abnormality when treating children with spinal cord injury, as these conditions have significant morbidity. MRI can identify injuries to the spinal cord that are not apparent with other modalities, and should be used when a child presents with a neurologic deficit but normal X-ray study or CT scan. Conclusion: With knowledge of these variations in pediatric anatomy, emergency physicians can appropriately identify injuries to the cervical spine and determine when further imaging is needed.     

Clearance of the cervical spine in multitrauma patients: The role of advanced imaging

The cervical spine is injured in 3% of major trauma patients. Radiographic clearance for injury must be provided efficiently and accurately. There are numerous choices for clearance that are now in clinical practice: lateral radiograph only, 3-view or 5-view cervical-spine (c-spine) series, flexion-extension radiographs, computed tomography (CT) with multiplanar reformations, and magnetic resonance imaging (MRI). This article reviews the literature on methods of c-spine clearance, and emphasizes the pitfalls of each modality. Although lateral radiographs detect 60% to 80% of c-spine fractures, a significant number of fractures are not visible, even when three views of the spine are obtained. The sensitivity of plain radiographs can be improved by attention to several subtle features, which are discussed. Flexion-extension radiographs in the acute setting have an unacceptably high false-negative and false-positive rate. CT detects 97% to 100% of fractures, but its accuracy in detection of purely ligamentous injuries has not been documented. Furthermore, CT is limited in patients with severe degenerative disease. MRI is highly sensitive in the detection of ligamentous injury, but not all cases of injury may cause instability. MRI is also much less sensitive than CT to fractures of the posterior elements of the spine, and to injuries of the craniocervical junction. The causes of missed cervical spine injury and delayed instability are discussed and shown in this article. An algorithm for the use of advanced imaging is proposed.     

Clinical outcomes of magnetic resonance imaging in blunt cervical trauma

Objectives: To determine whether MRI of the cervical spine resulted in a change in management of patients with blunt trauma and normal plain X‐ray (XR)/CT of the cervical spine. Methods: An explicit chart review was conducted of patients seen at a Level 1 trauma centre over a 1 year period. Clinical details were extracted from the charts of patients with blunt trauma who had a normal plain XR and CT scan of the cervical spine and who underwent cervical spine MRI. A comparison of clinical details was made between those with a normal/abnormal MRI secondary to the acute injury. Results: One hundred and thirty‐four patients met entry criteria. Discharge non‐operative management of the cervical spine was associated with a change in management by the MRI result (P < 0.0001) where MRI of the cervical spine occurred a median of 3 days (interquartile range 0–4.5, range 0–137) after the injury. The MRI occurred before discharge 90% of the time in both groups. Operative management occurred in three patients and was delayed until after first outpatient review in two patients. Conclusions: An abnormal MRI after normal plain XR and CT cervical spine studies resulted in a change in non‐operative management at discharge. Early MRI resulted in one patient receiving surgery before discharge. No unstable injuries were detected by MRI that were not evident on plain XR or CT cervical spine.     

Imaging of acute cervical spine trauma.

Over the past 15 years there have been dramatic changes in the approach to imaging acute cervical spine trauma. This article addresses the current thoughts and controversies regarding the most appropriate techniques to evaluate the patient with cervical spine trauma, with an emphasis on the role of computed axial tomography (CT) and magnetic resonance imaging (MRI). The issue of clinical versus radiographic evaluation of low-risk patients is also discussed.     

The cervical spine: radiologist's perspective

This article provides an essential curriculum in cervical spine radiology. It discusses the uses of plain radiographs, MR imaging, computed tomography (CT), and CT myelography, in addition to the methodologies of discography, epidural injections under visualization, and facet and nerve root injections. It explains how radiographic images of the cervical spine can differentiate tumors, inflammation, recent or prior trauma, and the range of discal, arthritic, neural, and vascular cervical pathologies and, just as importantly, when they cannot.     

Clinical algorithm for preventing missed diagnoses of occult cervical spine instability after acute trauma: A case report

BACKGROUNDMissed or delayed diagnosis of cervical spine instability after acute trauma can have catastrophic consequences for the patient, resulting in severe neurological impairment. Currently, however, there is no consensus on the optimal strategy for diagnosing occult cervical spine instability. Thus, we present a case of occult cervical spine instability and provide a clinical algorithm to aid physicians in diagnosing occult instability of the cervical spine.CASE SUMMARYA 57-year-old man presented with cervical spine pain and inability to stand following a serious fall from a height of 2 m. No obvious vertebral fracture or dislocation was found at the time on standard lateral X-ray, computed tomography, and magnetic resonance imaging (MRI). Subsequently, the initial surgical plan was unilateral open-door laminoplasty (C3-7) with alternative levels of centerpiece mini-plate fixation (C3, 5, and 7). However, the intraoperative C-arm fluoroscopic X-rays revealed significantly increased intervertebral space at C5-6, indicating instability at this level that was previously unrecognized on preoperative imaging. We finally performed lateral mass fixation and fusion at the C5-6 level. Looking back at the preoperative images, we found that the preoperative T2 MRI showed non-obvious high signal intensity at the C5-6 intervertebral disc and posterior interspinous ligament.CONCLUSIONMRI of cervical spine trauma patients should be carefully reviewed to detect disco-ligamentous injury, which will lead to further cervical spine instability. In patients with highly suspected cervical spine instability indicated on MRI, lateral X-ray under traction or after anesthesia and muscle relaxation needs to be performed to avoid missed diagnoses of occult cervical instability.     

Contrast-enhanced magnetic resonance imaging of the spine

MRI of the spine and its contents is fast becoming the study of choice over CT myelography for the evaluation of spinal pathology. MRI is able to generate sagittal and coronal images in addition to axial images, to image the entire spine, and to produce a myelogramlike picture. These capabilities give MRI a distinct advantage over CT myelography not only because no intrathecal contrast injection is needed but also because intramedullary lesions, edema, and syrinx may be differentiated from each other by conventional, noncontrast, spin-echo MRI. This article reviews the current philosophies regarding contrast-enhanced MRI with gadopentate dimeglumine in the evaluation of the spine and its contents. It will provide an imaging strategy and approach to evaluation, briefly discuss spin-echo and gradient-echo pulse sequences, and give contrast indications focusing on disorders that benefit from the use of injected, intravenous gadopentate dimeglumine. Potential imaging artifacts related to spin-echo and gradient-echo imaging pertinent to imaging of the spine will also be discussed.     

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.     

Biomechanics of the cervical spine 4: major injuries.

This review presents considerations regarding major cervical spine injury, including some concepts that are presently undergoing evaluation and clarification. Correlation of certain biomechanical parameters and clinical factors associated with the causation and occurrence of traumatic cervical spine injuries assists in clarifying the pathogenesis and treatment of this diverse group of injuries. Instability of the cervical column based on clinical and mechanistic perspectives as well as the role of ligaments in determining instability is discussed. Patient variables such as pre-existing conditions (degenerative disease) and age that can influence the susceptibility or resistance to injury are reviewed. Radiological considerations of major injuries including dynamic films, CT and MRI are presented in the diagnosis and treatment of cervical trauma. Specific injury patterns of the cervical vertebral column are described including attention to the relative mechanisms of trauma. From a biomechanical perspective, quantification of injury tolerance is discussed in terms of external and human-related variables using laboratory-driven experimental models. This includes force vectors (type, magnitude, direction) responsible for injury causation, as well as potential influences of loading rate, gender, age, and type of injury.     

影像学在诊断颈椎病中的应用

目的通过对85例颈椎病影像学资料进行分析,探讨颈椎病的影像学特征及其X线片、CT、MRI及MRA检查方法的选择原则,以便临床上对不同类型以及不同程度的颈椎病选择合适的诊断技术。方法 2005年6月2009年7月,85例均行颈椎标准X线片、CT、MRI及MRA检查,对其影像学资料进行分析。结果颈椎病以椎体及小关节增生、生理曲度改变、椎间隙变窄和局部失稳为常见X线表现,X线片、CT、MRI及MRA对颈椎病的诊断有不同的优点及限度。结论 X线片为首选检查方法 ,绝大部分可明确诊断,特殊情况加做CT、MRI或MRA检查。     

Imaging the degenerative diseases of the lumbar spine

Degenerative changes of the spine may involve the disc space, the facet joints, or the supportive and surrounding soft tissues. MR imaging is ideally suited for delineating the presence, extent, and complications of degenerative spinal disease. Other imaging modalities such as radiography, myelography, and CT may provide complimentary information in selected cases. Percutaneous procedures may be used to confirm that a morphologic abnormality is the source of symptoms. Correlation with clinical and electrophysiologic data is also helpful for accurate diagnosis. Combining the information obtained from imaging studies with the patient's clinical presentation is mandatory for determining the appropriate patient management strategy, especially true in patients afflicted with any condition directly attributed to the degenerative processes of the spine.     

Radiology of acute spinal trauma

Radiologic diagnostic modalities utilized to evaluate acute spine trauma include plain films, tomography, computerized tomography (CT), myelography and CT-myelography, and magnetic resonance imaging. The initial evaluation is aimed at delineating the nature and extent of both boney and soft tissue injuries, with particular attention directed toward differentiating intrinsic cord damage from extrinsic spinal cord or nerve root compression that may respond to surgical intervention. The selection of the optimal radiologic diagnostic algorithm requires familiarization with the techniques and limitations of each diagnostic procedure.     

Dynamic weight-bearing cervical magnetic resonance imaging: technical review and preliminary results

BACKGROUND: Conventional magnetic resonance imaging (MRI) of complex cervical spine disorders may underestimate the magnitude of structural disease because imaging is performed in a nondynamic non-weight-bearing manner. Myelography provides additional information but requires an invasive procedure. METHODS: This was a prospective review of the first 20 upright weight-bearing cervical MRI procedures with patients in the flexed, neutral, and extended positions conducted in an open-configuration MRI unit. RESULTS: This technique clearly illustrated the changes in spinal cord compression, angulation, and spinal column alignment that occur during physiologic movements with corresponding changes in midsagittal spinal canal diameter (P < 0.05). Image quality was excellent or good in 90% of the cases. CONCLUSIONS: Dynamic weight-bearing MRI provides an innovative method for imaging complex cervical spine disorders. This technique is noninvasive and has adequate image quality that may make it a good alternative to cervical myelography.     

Diagnostic capabilities of magnetic resonance imaging and computed tomography in acute cervical spinal column injury

The present study was conducted to evaluate the imaging capabilities of magnetic resonance imaging (MRI) in evaluating acute cervical spinal column injury and compare these results to that of computed tomographic (CT) imaging. Forty-nine patients undergoing MRI at a Level I and regional spinal cord trauma center to evaluate cervical spinal column injury were studied. Seventy-one injuries were identified by MRI. These injuries were classified as osseous (fracture/dislocation) (n = 21), disc herniation (n = 29), and spinal cord injury (edema/contusion/transection) (n = 21). Diagnostic imaging results in 33 of the 49 patients undergoing both MRI and CT were compared. CT demonstrated 22 fracture/dislocations compared to 10 on MRI. MRI demonstrated 19 disc protrusions compared to 7 on CT. Additionally, MR imaged 13 cord injuries as compared to 0 by CT. MR imaging proved superior in demonstrating spinal cord pathology and intervertebral disc herniation. CT was superior to MRI in demonstrating osseous injury. CT and MRI may be useful together in determining presence and extent of spinal column injury.     

Evaluation and management of acute cervical spine trauma

The evaluation and management of cervical spine injuries is a core component of the practice of emergency medicine. This article focuses on evaluation and management of blunt cervical spine trauma by the emergency physician. Pertinent anatomy of the cervical spine and specific cervical spine fractures are discussed, with an emphasis on unstable injuries and associated spinal cord pathology. The association of vertebral artery injury with cervical spine fracture is addressed, followed by a review of the most recent literature on prehospital care. Initial considerations in the emergency department, including cervical spine stabilization and airway management, are reviewed. The most current recommendations for cervical spine imaging with regard to indications and modalities are covered. Finally, emergency department management and disposition of patients with spinal cord injuries are reviewed.     

Are Plain Radiographs Sufficient to Exclude Cervical Spine Injuries in Low-Risk Adults?

Background

The routine use of clinical decision rules and three-view plain radiography to clear the cervical spine in blunt trauma patients has been recently called into question.

Clinical Question

In low-risk adult blunt trauma patients, can plain radiographs adequately exclude cervical spine injury when clinical prediction rules cannot?

Evidence Review

Four observational studies investigating the performance of plain radiographs in detecting cervical spine injury in low-risk adult blunt trauma patients were reviewed.

Conclusion

The consistently poor performance of plain radiographs to rule out cervical spine injury in adult blunt trauma victims is concerning. Large, rigorously performed prospective trials focusing on low- or low/moderate-risk patients will be needed to truly define the utility of plain radiographs of the cervical spine in blunt trauma.     

Trauma radiology: Part IV. Imaging of acute craniocerebral trauma

Diagnostic imaging has a key role in diagnosis and management of patients sustaining craniocerebral injuries from trauma. We review the current role of skull radiography, computed tomography (CT), and magnetic resonance (MR) in imaging patients sustaining craniocerebral trauma, and we describe the appearance of major forms of pathology as depicted by each modality. CT scan is used to assess quickly the extent of injury and to triage patients to observation, medical, or neurosurgical management. CT findings can be divided into primary craniocerebral injuries, including skull fractures; extraaxial hematomas (subdural and epidural); intraparenchymal injury, such as hematoma, contusion, and diffuse axonal shearing; and intraventricular or subarachnoid hemorrhage. Secondary manifestations of injury, such as cerebral edema and herniation, are also identified, and their course can be followed by serial CT. CT is crucial in assessing the outcome of surgical intervention and in identifying potential delayed complications of either head trauma or surgical intervention, including infection, delayed hemorrhage, cerebral infarction, and tension pneumocephalus. In recent years, MRI has been shown to be valuable in diagnosing cerebral injury. MRI has generally been shown to have greater overall accuracy than CT in identifying and characterizing most forms of traumatic cerebral pathology, but it is less accurate at demonstrating subarachnoid hemorrhage acutely, pneumocephalus, and calvarial fractures, particularly those involving the skull base. Moreover, MRI is still more difficult to perform than CT in critically ill patients, and it is generally far more time-consuming. However, MRI is unequivocally more accurate than CT at revealing certain lesions, particularly brainstem contusion, diffuse axonal shearing, predominantly nonhemorrhagic contusions, and thin collections of blood adjacent to bone, and it should be used selectively when these injuries are suspected.