C-Spine Evaluation and Clearance
Cervical spine injury is present in 2-6% of all trauma patients, and it can be a cause of major long-term disability.1 Overall, between 50% and 64% of spinal injuries involve the cervical spine.2 The risk of a cervical spine injury is greatest in patients with:
- Focal neurologic deficit
- Age greater than 50
- High-energy mechanism of injury
- The presence of a head injury3
All trauma patients require a full work-up for a spinal cord injury, the sooner the better: An early cervical spine evaluation and diagnosis can limit long-term sequelae. Complaints of pain or posterior midline tenderness in trauma patients require further work-up.
"Cervical spine clearance after blunt trauma is defined as accurately confirming the absence of a cervical spine injury."4
- The patient must be extricated and immobilized at the accident scene to avoid further neurologic injury.5
- Align the head and neck with the long axis of the trunk.6
- Utilize a cervical collar, sandbags, tape, and a spine board to immobilize the patient's head and neck.
- Maintain log roll precautions for transport.
- Use a Kendrick Extrication device for patients enclosed in tight spaces.7
- Avoid cervical extension, which would narrow the spinal canal. Instead, place the neck in neutral alignment.8
- Pediatric patients require special attention. Use a pediatric spine board with cut-out for occiput,9 or elevate the trunk.
- Leave helmets and shoulder pads in place.
- Obtain a preliminary neurologic assessment in the field.
Advanced Trauma Life Support (ATLS) Protocol
- The ATLS Protocol was developed by the American College of Surgeons to provide reproducible, efficient methods of injury identification in a trauma patient.10
- All trauma patients are presumed to have a cervical spine injury until proven otherwise.
- The cervical collar can be removed if the patient is awake, alert, and sober; has no neurologic abnormalities or cervical tenderness; and exhibits full, painless range of motion.
- Pain, tenderness, neurologic abnormality, or distracting injury warrant radiographic imaging studies.
- Optimize perfusion (MAP > 85mm Hg), especially if a spinal cord injury is suspected.
- Evaluate the patient for neurogenic shock: loss of sympathetic outflow resulting in hypotension and bradycardia. Treat with fluid boluses and vasopressors.11
- Maintain spine precautions with an unresponsive patient until the assessment is completed or a spinal injury is identified.
- Mechanism of injury
- Report of gross neurologic function in the field
- History of transient motor or sensory changes
- History of previous cervical spine abnormalities or trauma
- Musculoskeletal exam
- Log roll the patient, using assistants to support the head, neck, and trunk.
- Inspect and palpate from occiput to the sacrum, and look for hemorrhage, abrasion, laceration, malalignment, or a palpable gap in the spinous processes.
- Test the range of motion only in asymptomatic patients.
- Turn the patient's head 45 degrees to each side. If there is no pain, actively flex and extend the neck.
- Neurologic examination
- Follow the American Spinal Cord Injury Association (ASIA) guidelines. The minimum exam that should be performed is listed in the chart below.12
- The maximum motor score is 100 points, and the maximum light touch and pin prick is 112 points.
- Rectal exam
- Assess for touch, pinprick, tone, voluntary contraction, and deep pressure sensation.
- In addition to normal upper and lower extremity reflexes, also assess:
- Babinski: Stroke the plantar foot from proximal lateral to distal medial. The toes will extend and splay if the patient has an upper motor neuron (UMN) lesion.
- Oppenheim: Rub the tibial crest proximal to distal. Again, the toes will extend and splay in the presence of a UMN lesion.
- Cremasteric: Stroke the medial thigh proximal to distal. There will be no scrotal motion if the patient has a T12-L1 lesion.
- Anal wink: Stroke the skin around anus. If the patient has an S2-4 lesion, anal sphincter contraction will not be apparent.
- Bulbocavernosis: Tug on the foley catheter or squeeze the penis or clitoris. Patients in spinal shock or those with an S3-4 lesion will not exhibit anal sphincter contraction.
Criteria for Imaging
- NEXUS (National Emergency X-ray Utilization Study) Criteria13
- NEXUS has a high sensitivity (99%) but a low specificity (12.9%) for detecting cervical injury.
- No focal neurologic deficit
- No posterior midline cervical tenderness
- Normal alertness
- No evidence of intoxication
- No distracting pain
- If all criteria are fulfilled, the cervical collar may be removed without imaging.
- Canadian C-spine Rule4,15
- The Canadian C-Spine Rule has better sensitivity and specificity (100% and 42%, respectively) than NEXUS, which may reduce unnecessary imaging. However, it is more complex than NEXUS.
- Imaging must be done if any of these high-risk factors are present:
- Age greater than 65 years
- Dangerous mechanism (fall greater than 3 feet or 5 stairs, axial load to head, high-speed motor vehicle accident, bicycle collision)
- Parasthesias in extremities
- No imaging is needed if the following low-risk factors allowing safe assessment of motion are present:
- Simple rear-end motor vehicle accident
- Sitting position in emergency room
- Ambulatory at any time
- Delayed onset of neck pain
- Absence of midline cervical tenderness
- No imaging is needed if the patient can rotate actively 45 degrees to each side.
- The lateral view is 83% sensitive and 97% specific for detecting cervical spine fracture.16
- Adding an open mouth view and AP view increases sensitivity to nearly 100%.16
- The open mouth view is essential for excluding C1 arch or C2 odontoid process fractures.
- The AP view assesses alignment of uncovertebral joints and spinous processes.
- Oblique views can be used to assess facet joints, pedicles, and lateral mass, especially at the cervico-thoracic junction.
- If the cervico-thoracic junction cannot be visualized on the lateral view, obtain a swimmer's lateral view or a CT scan.
- Obtain a CT scan if the patient has normal x-rays but persistent cervical tenderness and pain.
- Flexion-extension views are not useful in the acute setting.17
- Pain and discomfort preclude adequate motion to assess for ligamentous injuries.
- Only perform a flexion-extension view on an alert patient under supervision. Flexion with an occult ligamentous injury may precipitate neurologic injury.1
- A CT scan is useful for determining the presence and extent of osseous injury. In fact, it is superior to MRI in this situation.
- In blunt trauma patients, CT scan detects 99.3% of cervical spine fractures.18
- Injuries in the transverse plane may be missed on axial cuts, ie, odontoid fractures.
- It is essential to obtain coronal and sagittal reconstructions
- MRI is indicated for evaluating neurologic deficits and ligamentous injuries.
- MRI is superior to CT for demonstrating spinal cord pathology, intervertebral disc herniation, and ligamentous disruption.
- MRI has limited usefulness as the primary means for initial cervical clearance.
- The highly sensitive images of MRI show muscular and soft tissue images that do not necessarily correlate with clinical instability.19
- MRI is not necessary if the initial screening CT is negative and the patient does not demonstrate neurologic abnormalities.
Anderson et al4 classified patients into four groups that dictate when to use which modalities.
- Use the Nexus criteria or the Canadian C-spine rules to determine if imaging is necessary.
- If the results are negative, the patient can be cleared without imaging.
Patient temporarily not assessable (intoxication or distracting injury, for example)
- Maintain the patient in a cervical collar until he or she can be assessed.
- In an urgent or severely injured patient, manage as obtunded (see below).
- Obtain AP, lateral, and odontoid plain x-rays.
- Flexion-extension views can be obtained in the subacute setting (2 weeks)17 if symptoms persist.
- Order a CT scan if x-rays are inadequate or if the patient is undergoing a CT for other reasons.
- MRI is appropriate for a patient with a spinal cord injury, progressive neurologic deterioration, or suspected ligamentous injury
- CT has evolved to be first line modality in obtunded patient in a trauma setting.
- If the CT is negative, Anderson supports discontinuing the cervical collar.
- MRI may find abnormalities even if the CT is negative; however, these abnormalities are not likely to be clinically significant.20
- The American College of Radiology advocates both CT and MRI for clearance of the obtunded patient.
- No clear consensus currently exists.
- Buckholtz RW et al. Rockwood and Greens Fractures in Adults. Seventh Edition. 2010. Chapter 41- Principles of Spine Trauma Care.
- Tator CH, Duncan EG, Edmonds VE, et al. Neurological recover, mortality and length of stay after acute spinal cord injury associated with changes in managament. Paraplegia 1995; 33(5): 254-262
- Blackmore CC, Emerson SS, Mann FA, et al. Cervical spine imaging in patients with trauma: determination of fracture risk to optimize use. Radilogy 1999; 211(3) 759-765
- Anderson PA et al. Clearing the Cervical Spine in the Blunt Trauma Patient. JAAOS. March 2010, Vol18: 149-159
- Podolsky S, Baraff LJ, Simon RR, et al. Efficacy of cervical spine immobilization methods. J Trauma 1983; 23(6):461-5
- Banta G, ed. Emergency Care and Transportation of the Sick and Injured. Menasha WI: American Academy of Orthopaedic Surgeons, 1987
- Winterberger , Jacomet H, Zafren K, et al. The use of extrication devices in crevasses accidents: official statement of the International Commission for Mountain emergency Medicine and the Terrestrial Rescue c=Commission of the International Commission for Alpine Rescue intended for physicians, paramedics and mountain rescuers. Wilderness Envrion Med 2008; 19 (2) 108-110
- Ching RP, Warson NA, Carter JW et al. The effect of post injury spinal position on canal occlusion in the cervical spine burst fracture model. Spine 1997; 22(15):1710-1715
- Apple DF Jr, Anson CA, Hunter JD, et al. Spinal cord injury in youth. Clin Pediatr (Phila) 1995; 34(2):90-95
- American College of Surgeons. Advanced trauma life support student manual. Chicago: Author 1989
- Consortium for Spinal Cord Medicine. Early acute management in adults with spinal cord injury: a clinical practice guideline for health care professionals. J Spinal Cord Med 2008; 31(4): 403-479
- American Spinal Cord Injury Association. International Standards for neurological classification of spinal injury. Atlanta Ga: Author 2008
- Hoffman JR, Mower WR, Wolfson AB, et al. Validity of a set of clinical criteria to rule out injury to the cervical spine in patients with blunt trauma. National Emergency X-Radiography Utilization Study Group. N Engl J Med 2000; 343(2):94-99
- Stiel IG, Clement CM, McKnight RD, et al. The Canadian C-spine rule versus the NEXUS low-risk criteria in patients with trauma. N Engl J Med 200; 349 (26):2510-2518
- Stiel IG, Wells GA, Vandemheem KL et al. The Canadian C-Spine rule for radiography in alert and stable trauma patients. JAMA 2001; 286(15):1841-1848
- MacDonald RL, Schwartz ML, Mirich D, et al. Diagnosis of Cervical Soine injuries in motor vehicle crash victims: how many x-rays are enough? J Trauma 1990; 30(4): 392-397
- Daffner RH, Hackney DB. ACR: Appropriateness Criteria on suspected spine trauma. J Amer Coll Radiol 2007; 4: 762-775
- Brown CV, Antevil JL, Sise MJ, Sack DI. Spiral computed tomography for the diagnosis of cervical, thoracic and lumbar spine fractures: Its time has come. J Trauma 2005; 58: 890-895
- Thuret S, Moon LD, Gage FH: Therapeutic Interventions after spinal cord injury. Nat Rev Neurosci 2006:7(8): 628-643
- Hogan GJ, Mirvis SE, Shanmuganathan K, Scalea TM: Exclusion of unstable cervical spine injury in obtunded patients with blunt trauma: Is MRI needed when mutli-detector row CT findings are normal? Radiology 2005; 237: 106-113