Clinical review: Spinal imaging for the adult obtunded blunt trauma patient: update from 2004

Radiological protocol in spinal trauma: literature review and Spinal Cord Society position statement

PURPOSE

The Spinal Cord Society constituted a panel tasked with reviewing the literature on the radiological evaluation of spinal trauma with or without spinal cord injury and recommend a protocol. This position statement provides recommendations for the use of each modality, i.e., radiographs (X-rays), computed tomography (CT), magnetic resonance imaging (MRI), as well as vascular imaging, and makes suggestions on identifying or clearing spinal injury in trauma patients.

METHODS

PubMed was searched for the corresponding keywords from January 1, 1980, to August 1, 2017. A MEDLINE search was subsequently undertaken after applying MeSH filters. Appropriate cross-references were retrieved. Out of the 545 articles retrieved, 105 relevant papers that address the present topic were studied and the extracted content was circulated for further discussions. A draft position statement was compiled and circulated among the panel members via e-mail. The draft was modified by incorporating relevant suggestions to reach a consensus.

RESULTS AND CONCLUSION

For imaging cervical and thoracolumbar spine trauma patients, CT without contrast is generally considered to be the initial line of imaging and radiographs are required if CT is unavailable or unaffordable. CT screening in polytrauma cases is best done with a multidetector CT by utilizing the reformatted images obtained when scanning the chest, abdomen, and pelvis (CT-CAP). MRI is indicated in cases with neurological involvement and advanced cervical degenerative changes and to determine the extent of soft tissue injury, i.e., disco-ligamentous injuries as well as epidural space compromise. MRI is also usually performed when X-rays and CT are unable to correlate with patient symptomatology. These slides can be retrieved under Electronic Supplementary Material.

Cervical spine clearance in the adult obtunded blunt trauma patient: A systematic review

BACKGROUND

A missed cervical spinal injury could have devastating consequences. Patients with a suspected cervical spinal injury are kept in rigid collars for cervical immobilisation. Prolonged collar use has important clinical implications. A well-defined guideline related to the removal of cervical collars from adult obtunded blunt trauma patients has not been developed.

AIM

We sought to determine if Magnetic Resonance Imaging offered a definitive benefit over Computer Tomography with respect to patient management.

METHOD

We searched Ovid Online, EBSCO, NICE Evidence Journals, Medline, PubMED, BNI, CINAHL and Google Scholar as well as the grey literature. Data extraction and synthesis were performed on studies that compared the radiologic findings and clinical outcomes of Computer Tomography scan and Magnetic Resonance Imaging in this patient group.

RESULTS

There is evidence that supports the safe discontinuation of cervical collar use after a negative multidetector Computer Tomography scan result alone. Magnetic Resonance Imaging may detect a significant number of ligamentous injuries, but such injuries are rarely of clinical significance because they rarely alter clinical management. Its use should be limited to specific circumstances.

CONCLUSION

It is important for institutions to re-examine the latest evidence regarding cervical spinal clearance in order to update their guidelines.

Traumatic cervical spine fractures in the adult

This article reviews fractures of the cervical spine, highlighting the pertinent goals of initial management, the indications for different imaging modalities and the different fracture patterns. Basic principles of management of these different fracture patterns are outlined.

Impact of MRI on changing management of the cervical spine in blunt trauma patients with a 'negative' CT scan

Background

Owing to the potential risks associated with missed injury, many blunt trauma patients with suspected cervical spine injury undergo some form of imaging technique which has progressed from primarily using plain radiography to relying on CT. Recently, studies have shown that in certain situations, adding MRI may improve the diagnostic accuracy over solely relying on CT.

Methods

Retrospective study of 3468 adult blunt trauma patients at a level I trauma center of which 94 with an initial negative CT scan underwent subsequent MRI. These 94 patients were classified as reliable or unreliable for examination; coded as either having a positive or negative MRI result; and assessed for a change in management.

Results

Of the 94 patients in the study population, 69 (73.4%) were deemed reliable and 25 (26.6%) deemed unreliable for examination. Overall, 65 (69.1%) patients had a positive MRI result—49 (71.0%) reliable and 16 (64.0%) unreliable—with some patients testing positive for more than one finding. There was no significant difference in positive MRI rates between reliable and unreliable patients. None of the 29 patients who had negative MRI had a change in management, while 31 of the 65 (47.7%) patients with positive MRI did have a change in management of either continued cervical collar immobilization or neck surgery.

Conclusions

The use of CT scans should be continued as the primary imaging technique for patients with suspected cervical spine injuries. In cases where obtundation or clinical suspicion exists for a false-negative CT scan, MRI should be considered as a supplement and should not be rejected solely based on the negative result of the CT.

Level of evidence

Level IV.

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

INTRODUCTION

The 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.

METHODS

A 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.

RESULTS

It 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.

CONCLUSIONS

Overall, 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.

Emergency department evaluation and treatment of cervical spine injuries

Most spinal cord injuries involve the cervical spine, highlighting the importance of recognition and proper management by emergency physicians. Initial cervical spine injury management should follow the ABCDE (airway, breathing, circulation, disability, exposure) procedure detailed by Advanced Trauma Life Support. NEXUS (National Emergency X-Radiography Utilization Study) criteria and Canadian C-spine Rule are clinical decision-making tools providing guidelines of when to obtain imaging. Computed tomography scans are the preferred initial imaging modality. Consider administering intravenous methylprednisolone after discussion with the neurosurgical consultant in patients who present with spinal cord injuries within 8 hours.

Injury after non-judicial hanging

Hanging is an important and increasingly common method of suicide in developed countries. Little is known about the true human pathophysiological changes and injury patterns associated with hanging and near hanging. Cervical spine injury is commonly reported; however, there is a paucity of large data sets concerning this injury. This review article focuses on the incidence of cervical spine and associated neck injuries and their role in morbidity and mortality following non-judicial hanging. A total of 26 heterogeneous studies were identified examining injury after hanging or near hanging. In total, there were 2795 patients; 1530 (54.7%) with true hanging and 1265 (45.3%) with near hanging. Cervical spine injury was reported in a total of 58 (2.08%) patients. Injuries to the airway and vessels of the neck seem rare. This is somewhat lower than the current accepted incidence for cervical spine injury after hanging or blunt force trauma. The overall incidence of cervical spine injury after hanging is low. Spinal immobilisation should probably be instituted depending on the mechanism of the hanging. However, a patient presenting with signs of life to an emergency department is unlikely to have a severe cervical spine injury.

Clinical applicability of magnetic resonance imaging in acute spinal cord trauma

PURPOSE

To assess the clinical application of magnetic resonance imaging (MRI) in patients with acute spinal cord trauma (SCT) according to the type, extension, and severity of injury and the clinical-radiological correlation.

METHODS

Diagnostic imaging [computed tomography (CT) and MRI] tests of 98 patients with acute SCT were analyzed to assess their clinical diagnostic value. The following radiological findings of SCT were investigated: vertebral compression fractures, bursts and dislocations, posterior element fractures, C1 and C2 lesions, vertebral listhesis, bone swelling, spinal canal compression, disk herniation, extradural hematoma, spinal cord contusions, spinal cord swelling, and posterior ligamentous complex (PLC) injuries.

RESULTS

The radiological findings were better visualized using MRI, except for the posterior elements (p = 0.001), which were better identified with CT. A total of 271 lesions were diagnosed as follows: 217 using MRI, 154 using CT, and 100 (36.9 %) using both MRI and CT. MRI detected 117 more lesions than CT.

CONCLUSION

MRI was significantly superior to CT in the diagnosis of bone swelling, PLC injury, disk herniation, spinal canal compression, spinal cord contusion and swelling present in SCT. MRI detected a larger number of lesions than CT and is highly useful for the diagnosis of soft tissue and intrathecal injuries.