Persistent Midline C-Spine Tenderness After a Negative CT Scan: What’s The Next Step?
- Sep 17th, 2018
- Kathy Staats
Author: Kathy Staats, MD (@Vochma730, EM & EMS Attending Physician, Stanford University) // Edited by: Alex Koyfman, MD (@EMHighAK) and Brit Long, MD (@long_brit)
A 28-year-old male with no past medical history is brought in by EMS in a C-collar with spinal precautions for neck pain after a rollover motor vehicle collision prior to arrival. The patient was driving at highway speed prior to the accident, did not have loss of consciousness, was a restrained driver, and airbags deployed. He required extrication by the fire department and did not ambulate prior to arrival in the ED.
His initial survey showed point tenderness to his cervical spine, with no other focal physical exam findings. The patient denies sensory deficits or subjective feelings of weakness. A non-contrast computed tomography (CT) is completed, which shows no obvious bony abnormality. In spite of pain medication, the patient continues to have point tenderness to his cervical spine.
What are the next steps for a patient with persistent C-spine tenderness, a negative CT, and no neurological deficits?
What is the role of magnetic resonance imaging (MRI)? When is it appropriate to discharge a patient in a rigid or soft cervical collar?
Cervical spine injuries occur in 3% of major trauma patients.1,2 Injuries have a bimodal distribution, with an initial peak between ages 15 and 29 years old and the second peak after age 65.2 Morbidity and mortality from cervical injuries are high. Litigation concerning missed cervical spine injuries is often severe, and the average payout in the United States is $2.9 million.3 For ED patients, a missed or delayed diagnosis of unstable cervical spine injuries is ten times more likely to be associated with neurological sequelae than injury diagnosed on initial evaluation.4 When assessing for these injuries, the literature is clear: both CT and MRI can be critical modalities in evaluating for unstable cervical spine injuries.5-7
Initial Imaging of the Cervical Spine: X-ray, CT, or MRI?
- CT is excellent for evaluationof spine alignment, detection of bony injuries, and hematomas involving the paravertebral soft tissues, craniocervical junction injuries, and signs of subcutaneous soft tissue trauma. Sensitivity approaches 97-100% and specificity 99-100% in detecting injury.1,6,7,25
- CT is highly sensitive, fast, practical, not limited by a patient’s pre-existing hardware, and is less claustrophobic for patients than MRIs.7
- 3D-CT reconstructions allow for visualization in multiple planes and provide superior injury detection when compared with plain x-ray. If an injury is strongly suspected, per the American College of Radiology, reconstructions should be completed.6,27
- MRI is superior in its ability to evaluate for acute disc herniation, ligamentous injury, edema, contusions, bony compression of the spinal cord, and epidural and subdural hemorrhage when compared to CT.8
- MRI is also the best diagnostic imaging for SCIWORA (spinal cord injury without radiographic abnormality) with studies documenting sensitivities of 89-100%.27
The use of MRI in awake, reliable patients without identification of bony abnormality on CT is controversial, even amongst neurosurgical specialists.2,5
Should awake, reliable patient with persistent midline tenderness after normal head CT undergo MRI?
In Support of an ED MRI:
Some studies suggest MRIs will catch important information missed by CT. In recent meta-analyses, injuries that required surgically intervention9 or prolonged rigid collar use10-12 were found on MRI after normal CTs. However, most changes to care involved using a collar and accounted for less than 1% of the study population. Schoenfeld’s meta-analysis showed a higher percentage of patients affected by a post-CT MRI, with 6% of the patients requiring management changes.9 Still less than 1% needed surgery based on new findings. These studies argued that an important aspect of using MRI, the postulated gold standard, is its negative predictive value and its use to exclude unstable cervical spine injury in patients with persistent pain or coma.9,10
Recently, two prospective, large, multi-center trials were completed to evaluate the utility of post-CT MRI. Both studies identified injuries requiring surgery with MRI that were not found on CT.14,15 The authors discussed however, that those patients made up a small percentage (<4% and 1%) of their overall number. In the Inaba study, all of the patients requiring surgery had a focal neurological finding, and two of the three had significant degenerative disease.15 Another large study in 2011 showed that 2.8% of the patients receiving an MRI following a negative CT had injuries requiring surgery.13 Overall, care was changed for a significant number of patients based on these studies.
Many studies noted two important aspects of MRI evaluation:
- Anecdotal evidence suggests if an MRI does not occur within 72 hours of the injury, the hemorrhage and edema would decrease too much for accurate evaluation.29
- Advanced cervical spine degeneration evident on CT, minor thoracolumbar fracture, severe neck pain, and multidirectional cervical spine forces were associated with increased injury extent and may indicate need for MRI in spite of a normal CT.2,13
In Support of Clearance following Normal CT Scan:
As CTs have improved in speed and quality, other studies have found the sensitivity and specificity of CT approach 100% for evaluation of unstable cervical spine injuries.3,15 As evidence mounts backing the accuracy of CT evaluations, some institutions are adopting a new practice pattern:
If no obvious neurological deficit exists, with negative CT, C-spine precautions are attempted to be cleared. No further testing is ordered if the patient’s midline tenderness resolves after CT and he/she is without neurological deficits and not altered or intoxicated.16
In the pro-early clearance studies, many commented on four consistencies regarding MRIs:
- The false positive rate of clinically insignificant soft-tissue injury is extremely high (up to 40%).9,10,12 This could cause unnecessary worry and cost. MRIs often identify other soft tissue injuries. Indeed, the utility of noting a single column injury within the spine is not yet known.1
- MRIs are significantly more expensive that CTs. They also take much longer to complete, costing the patient time, and the system a hospital bed.
- Lying flat during MRI can be dangerous, especially when wearing a c-collar.
- Most authors found that patients with abnormal MRIs already had these findings seen on CT.
The Royal Australia and New Zealand College of Radiologists have released modules on traumatic cervical injuries, which allows clearance following a negative CT and non-concerning physical exam.17
A Word on Flexion-Extension Imaging:
Previously flexion-extension x-rays were recommended when there was concern for ligamentous instability. Studies have now shown flexion-extension x-rays have low sensitivity for injury, and patients are kept in cervical collars and the hospital longer than patients with CT evaluations of their cervical injuries. Additionally, these imaging studies are inadequate based on patient positioning, body habitus, or technician experience, and patients often need further imaging.28 However, allowing the movement of the cervical spine in the context of concern for its laxity could be dangerous. Additionally, getting adequate films could be difficult, especially if complicated by muscle spasm.2,18 If suspicion is high with a negative CT, MRI should be the next step.
The Cervical Collar:
Prolonged immobilization in a hard cervical collar has been associated with:
- Decreased cerebral venous return
- Secondary brain injury
- Pulmonary complications
- Decreased mobilization
- Breathing restriction including decreased functional residual capacity
- Tissue ischemia
- Difficult nursing care
- Increased risk of aspiration16,19-22
Typical hard collars are used for patients following surgery or with fractures or dislocations of their C-spine.21 Hard collars should be reserved for patients with unstable cervical injuries or significant sprains and strains. For patients requiring a hard or rigid collar, the Aspen or Philadelphia models may be best at avoiding flexion and extension. The Aspen is also effective at limiting rotation most effectively.23 These collar types are chosen to optimize immobility, which is an important factor to allow for healing of unstable fractures and ligamentous injury.
For patients with “whiplash,” the paraspinal neck pain common following a motor vehicle collision, soft collars are often prescribed to patients for comfort. Several studies have shown that a soft collar, when compared with early mobility and/or physiotherapy of the neck, may be detrimental, delaying healing, causing muscle weakness, and potential increased rates of pain and stiffness.21 Currently, little evidence exists to suggest superiority of soft collar use versus other interventions.21,24
Our patient receives his CT, which shows no acute injury. His midline cervical tenderness is still present but improving, and he has no previous cervical spine problems. His motor and sensory exam is repeated and unchanged, and he continues to deny neurological symptoms. The patient’s cervical spine is clinically cleared, and he is discharged with early mobility and physiotherapy recommendations.
- Cervical spine trauma can be deadly and unstable injuries should always be considered.
- Strict cervical spine precautions should be used until a patient can be cleared clinically through the NEXUS or Canadian C-spine Criteria or with imaging.
- In neurologically intact patients with a negative CT, a patient’s C-spine may be cleared in the proper clinical context, without the risk factors for abnormal MRIs, even with mild ongoing midline tenderness.
- Unstable cervical spine or ligamentous injuries should maintain a rigid C-collar as part of treatment.
- Stable cervical injuries can use a soft collar for symptom control, but evidence shows early mobility and training may improve early recovery and mobility.
From Dr. Hanson at Hanson’s Anatomy:
References / Further Reading:
- Crim, Julia R, et al. “Clearance of the Cervical Spine in Multitrauma Patients: The Role of Advanced Imaging.” Seminars in Ultrasound, CT and MRI, vol. 22, no. 4, 2001, pp. 283–305., doi:10.1016/s0887-2171(01)90023-x.
- Kaji, Amy, et al. “Spinal Column Injuries in Adults: Definitions, Mechanisms, and Radiographs.” UpToDate, 2018. Accessed May 27, 2018.
- Resnick, Shelby, et al. “Clinical Relevance of Magnetic Resonance Imaging in Cervical Spine Clearance.” JAMA Surgery, vol. 149, no. 9, Jan. 2014, p. 934., doi:10.1001/jamasurg.2014.867.
- Diaz, Jose J., et al. “The Early Work-Up For Isolated Ligamentous Injury Of The Cervical Spine: Does Ct-Scan Have A Role?” The Journal of Trauma: Injury, Infection, and Critical Care, vol. 57, no. 2, 2004, p. 453., doi:10.1097/00005373-200408000-00112.
- Shah, Lubdha M., and Jeffrey S. Ross. “Imaging of Spine Trauma.” Neurosurgery, vol. 79, no. 5, 2016, pp. 626–642., doi:10.1227/neu.0000000000001336.
- Ahuja, Christopher, and Michael Fehlings. “Acute Cervical Spine Trauma.” BMJ Best Practice, 21 Nov. 2017.
- Utz, Michael, et al. “MDCT and MRI Evaluation of Cervical Spine Trauma.” Insights into Imaging, vol. 5, no. 1, Dec. 2013, pp. 67–75., doi:10.1007/s13244-013-0304-2.
- Marx, John A., et al. “Spinal Injuries.” Rosen’s Emergency Medicine Concepts and Clinical Practice, Mosby/Elsevier, 2010.
- Schoenfeld, Andrew J., et al. “Computed Tomography Alone Versus Computed Tomography and Magnetic Resonance Imaging in the Identification of Occult Injuries to the Cervical Spine: A Meta-Analysis.” The Journal of Trauma: Injury, Infection, and Critical Care, vol. 68, no. 1, 2010, pp. 109–114., doi:10.1097/ta.0b013e3181c0b67a.
- Muchow, Ryan D., et al. “Magnetic Resonance Imaging (MRI) in the Clearance of the Cervical Spine in Blunt Trauma: A Meta-Analysis.” The Journal of Trauma: Injury, Infection, and Critical Care, vol. 64, no. 1, 2008, pp. 179–189., doi:10.1097/01.ta.0000238664.74117.ac.
- Malhotra, Ajay, et al. “Utility of MRI for Cervical Spine Clearance after Blunt Traumatic Injury: a Meta-Analysis.” European Radiology, vol. 27, no. 3, 2016, pp. 1148–1160., doi:10.1007/s00330-016-4426-z.
- Kirschner, Jonathan, and Rawle A. Seupaul. “Does Computed Tomography Rule Out Clinically Significant Cervical Spine Injuries in Patients With Obtunded or Intubated Blunt Trauma?” Annals of Emergency Medicine, vol. 60, no. 6, 2012, pp. 737–738., doi:10.1016/j.annemergmed.2012.01.026.
- Ackland, Helen M., et al. “Cervical Spine Magnetic Resonance Imaging in Alert, Neurologically Intact Trauma Patients With Persistent Midline Tenderness and Negative Computed Tomography Results.” Annals of Emergency Medicine, vol. 58, no. 6, 2011, pp. 521–530., doi:10.1016/j.annemergmed.2011.06.008.
- Maung, Adrian A., et al. “Cervical Spine MRI in Patients with Negative CT.” Journal of Trauma and Acute Care Surgery, vol. 82, no. 2, 2017, pp. 263–269., doi:10.1097/ta.0000000000001322.
- Inaba, Kenji, et al. “Cervical Spinal Clearance.” Journal of Trauma and Acute Care Surgery, vol. 81, no. 6, 2016, pp. 1122–1130., doi:10.1097/ta.0000000000001194.
- Patel, Mayur B., et al. “Cervical Spine Collar Clearance in the Obtunded Adult Blunt Trauma Patient.” Journal of Trauma and Acute Care Surgery, vol. 78, no. 2, 2015, pp. 430–441., doi:10.1097/ta.0000000000000503.
- Goergen, S, et al. “Adult Cervical Spine Trauma.Education Modules for Appropriate Imaging Referrals:” Royal Australian and New Zealand College of Radiologists, 2015.
- Chew, Brandon G., et al. “Cervical Spine Clearance in the Traumatically Injured Patient: Is Multidetector CT Scanning Sufficient Alone?” Journal of Neurosurgery: Spine, vol. 19, no. 5, 2013, pp. 576–581., doi:10.3171/2013.8.spine12925.
- Dunham, C Michael, et al. “Risks Associated with Magnetic Resonance Imaging and Cervical Collar in Comatose, Blunt Trauma Patients with Negative Comprehensive Cervical Spine Computed Tomography and No Apparent Spinal Deficit.” Critical Care, vol. 12, no. 4, 2008, doi:10.1186/cc6957.
- Schuster, Rob. “Magnetic Resonance Imaging Is Not Needed to Clear Cervical Spines in Blunt Trauma Patients With Normal Computed Tomographic Results and No Motor Deficits.” Archives of Surgery, vol. 140, no. 8, Jan. 2005, p. 762., doi:10.1001/archsurg.140.8.762.
- Muzin, Stefan, et al. “When Should a Cervical Collar Be Used to Treat Neck Pain?” Current Reviews in Musculoskeletal Medicine, vol. 1, no. 2, Dec. 2007, pp. 114–119., doi:10.1007/s12178-007-9017-9.
- Blackham, Julian, and Jonathan Benger. “’Clearing’ the Cervical Spine in the Unconscious Trauma Patient.” Trauma, vol. 13, no. 1, 2010, pp. 65–79., doi:10.1177/1460408610385978.
- Evans, Nicholas Rhys, et al. “A 3D Motion Analysis Study Comparing the Effectiveness of Cervical Spine Orthoses at Restricting Spinal Motion through Physiological Ranges.” European Spine Journal, vol. 22, no. S1, Apr. 2013, pp. 10–15., doi:10.1007/s00586-012-2641-0.
- Logan, A J. “Management of Whiplash Injuries Presenting to Accident and Emergency Departments in Wales.” Emergency Medicine Journal, vol. 20, no. 4, Jan. 2003, pp. 354–355., doi:10.1136/emj.20.4.354.
- Mathen, Reshma, et al. “Prospective Evaluation of Multislice Computed Tomography Versus Plain Radiographic Cervical Spine Clearance in Trauma Patients.” The Journal of Trauma: Injury, Infection, and Critical Care, vol. 62, no. 6, 2007, pp. 1427–1431., doi:10.1097/01.ta.0000239813.78603.15.
- Osborn, A.G. “ACR Appropriateness Criteria® on Suspected Spine Trauma.” Yearbook of Diagnostic Radiology, vol. 2008, 2008, pp. 310–312., doi:10.1016/s0098-1672(08)79066-0.
- Bozzo, Anthony, et al. “The Role of Magnetic Resonance Imaging in the Management of Acute Spinal Cord Injury.” Journal of Neurotrauma, vol. 28, no. 8, 2011, pp. 1401–1411., doi:10.1089/neu.2009.1236.
- Oh, Jason Jaeseong, et al. “Diagnostic Accuracy of Flexion-Extension Radiography for the Detection of Ligamentous Cervical Spine Injury Following a Normal Cervical Spine Computed Tomography.” Emergency Medicine Australasia, vol. 28, no. 4, 2016, pp. 450–455., doi:10.1111/1742-6723.12612.
- Stassen, Nicole A., et al. “Magnetic Resonance Imaging in Combination with Helical Computed Tomography Provides a Safe and Efficient Method of Cervical Spine Clearance in the Obtunded Trauma Patient.” The Journal of Trauma: Injury, Infection, and Critical Care, vol. 60, no. 1, 2006, pp. 171–177., doi:10.1097/01.ta.0000197647.44202.de.