Spine

Approximately 30% of patients with polytrauma in the United States have a spine injury documented during their evaluation, of which about 13%, or 4% of all polytrauma victims, have spine injuries that require surgical stabilization. Spinal cord injury affects approximately 12,000 of these patients a year and is associated with an estimated yearly societal cost of $9.7 billion (in 1998 dollars). Although injuries to the thoracolumbar spine outnumber cervical injuries approximately 4 : 1, most spinal cord injuries occur at the cervical level.

Initial Emergency Department Treatment

The emergency department evaluation of a patient with concern for injury should include a thorough examination taking into consideration the importance of looking for other injuries (e.g., head, thoracic, abdominal, extremity) and the potential for issues that may have caused the trauma (e.g., hypoglycemia, syncope, seizure) while initiating or maintaining spinal immobilization until the patient can be cleared of spinal cord injury. Initial patient evaluation and trauma management are discussed further in Chapters 1 and 5 respectively. Spinal immobilization should be removed as soon as possible owing to its clear and proven complications. (See discussion of cervical spine clearance later.) Advanced trauma life support and advanced cardiac life support guidelines may provide a good foundation for the evaluation that the patient needs to undergo.

Airway management in a patient with suspected cervical spine injury is fraught with complications, and the importance of minimizing movement while managing the airway must be kept in mind.

Physical Examination

The physical examination should be thorough and include evaluation for other injuries while taking into consideration key points that would be helpful in the patient with a spine injury. In a patient with a spine injury, the level of neurologic injury is best evaluated by a focused motor and sensory examination.

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Motor
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  C3-5—diaphragmatic movement
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  C5—elbow flexion
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  C6—wrist extension
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  C7—wrist flexion
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  C8—finger flexion
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  T1—finger abduction
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  L1-2—hip abduction
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  L3—knee extension
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  L4—ankle dorsiflexion
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  L5—great toe extension
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  S1—great toe flexion, ankle plantar flexion
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Sensory ( Fig. 8-1 )
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  Injury recording tool ( Fig. 8-2 )
  
  FIGURE 8-2
  
  Injury recording tool.
  
  (Courtesy American Spinal Injury Association, Atlanta, GA.)
FIGURE 8-1

Sensory dermatome chart. C4 includes the upper chest just superior to T2.

(From Browner BD, Jupiter JB, Levine AM, et al, editors: Skeletal trauma: basic science, management, and reconstruction, ed 4, Philadelphia, 2008, Saunders.)

Spinal cord syndromes are patterns of injuries with associated neurologic findings that are helpful in categorizing spinal cord injuries.

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Cord Syndromes
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  Central cord syndrome
Central cord syndrome is characterized by motor and sensory impairment in the arms and hands greater than the legs resulting from an injury to the central part of the cervical spinal cord. This syndrome is commonly seen in hyperextension injuries in patients without obvious injuries.
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  Anterior cord syndrome
Anterior cord syndrome is characterized by loss of motor function and pain and temperature sensation with preservation of fine touch and proprioceptive function below the level of the lesion. This syndrome is often caused by occlusion of the anterior spinal artery.
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  Brown-Séquard syndrome
Brown-Séquard syndrome is characterized by unilateral loss of motor function, touch, and vibration with contralateral loss of pain and temperature sensation secondary to spinal cord hemisection.
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  SCIWORA
Spinal cord injury without radiographic abnormality (SCIWORA) is seen in children who may have complete quadriplegia secondary to greater plastic deformation of the spine than tolerated by the neural tissues. SCIWORA can manifest hours after the initial injury.
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  Neurogenic shock
Neurogenic shock syndrome comprising hypotension, bradycardia, and absence of reflexes can manifest in patients with complete or incomplete spinal cord injuries above T6 resulting from a loss of sympathetic tone in the face of maintained vagal tone when the spinal cord is injured. Neurogenic shock should be recognized and treated aggressively with fluid resuscitation and vasopressors.

Diagnostic Imaging

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Plain Radiographs

The sensitivity of radiographs for identifying cervical spine injury has been estimated at 50% to 80%. Inadequate visualization at the occipitocervical and cervicothoracic junctions is a major limitation of plain x-rays. Although computed tomography (CT) has generally replaced plain radiographs for cervical spine clearance in cases of high-risk patients, plain radiographs can still play an important role in cooperative, neurologically normal patients with minor trauma and a benign cervical spine examination who cannot be cleared clinically. The patient’s body habitus and ability to cooperate with the technique needed to get the films should also be taken into consideration.

The typical set of cervical spine films includes anteroposterior, lateral, and odontoid views. The lateral view offers the most in regard to injury detection. Disruption of anatomic lines and symmetric joint spaces provides clues to fractures and instability.

Oblique and swimmer’s views improve sensitivity only slightly and generally are not recommended. Flexion and extension views can identify dynamic instability; however, the efficacy, utility, and cost-effectiveness of flexion and extension films in the acute setting has been challenged.
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CT

Multidetector CT scanning has generally replaced plain radiographs for detecting spine injuries in certain populations. In many trauma centers, CT is the study of choice for patients at moderate to high risk of spine injury; this is especially the case if patients are being scanned to assess for other injuries, which significantly improves cost-effectiveness. More recent studies support the use of CT, which identifies 99.3% of all cervical spine fractures. The missed injuries are typically minor and require minimal to no treatment. However, soft tissue injuries, mainly ligamentous in nature, are poorly detected by CT scan with a negative predictive value of 78%. In a small percentage of patients, ligamentous injuries are significant enough to require surgical intervention and prolonged immobilization.
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Magnetic Resonance Imaging (MRI)

The indications for acute MRI in the setting of suspicion of acute spine trauma are still being defined. Generally, patients with neurologic or cognitive deficits (i.e., obtunded patients) may undergo MRI, especially in cases where cervical collar clearance or operative stabilization is paramount. However, these are typically patients for whom there is significant difficulty in obtaining MRI because of mechanical ventilation, risk of leaving the intensive care environment, and the need for nursing staff to accompany the patient. Controversy persists regarding the use of multidetector CT only versus additional MRI for cervical spine assessment. Based on a meta-analysis yielding 1550 patients with negative multidetector CT, the management of 6% was altered based on the MRI results, and 1% required surgical stabilization.
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CT Angiography and CT Myelography

There is currently little to support the use of CT angiography or myelography in the emergent evaluation of a patient with suspected spine injury.
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Points to Consider
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  A plain lateral x-ray should be considered in patients with clinically obvious spinal cord injuries so that rapid reduction might be performed if indicated.
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  Most patients who cannot be cleared clinically should have either three-view cervical spine radiographs or cervical CT.
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  If a patient is having CT for another reason, it is often more efficient management to include a cervical CT scan. If possible, scanning down to T4 can ease evaluation of the cervical thoracic junction, a region that is difficult to image with plain radiography, especially in large patients.
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  CT has significantly better sensitivity (>99%) than plain radiographs (55% to 75%) but has 100 times greater radiation dose and an increased risk of cancer.
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  MRI is not routinely indicated in the evaluation of trauma.
  - MRI is indicated in the initial evaluation of suspected or known spine injury in patients with unexplained neurologic deficits, in patients with progressive deterioration, in patients before reduction who are have facet dislocations but are neurologically intact, and in patients for preoperative evaluation.
  - MRI should be performed to answer specific questions left unanswered by CT and in the evaluation of a neurologic deficit or when it is considered essential by a consulting expert in formulating a disposition for the patient.

Cervical Spine

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Anatomy

The cervical spine is composed of seven vertebrae. The anatomic arrangement of the cervical spine allows for a high degree of mobility in flexion, extension, and rotation. There is significant lateral mobility as well. The high degree of mobility coupled with the burden of supporting the weight of the head leaves the cervical spine vulnerable to injuries. Because spinal cord injuries at the level of the cervical vertebrae are devastating, the stability of the bones and ligaments of the cervical spine is probably the most important in the body.
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History and Mechanism of Injury for Cervical Spine Injuries
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  Significant spine injuries typically involve high-energy trauma.
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  The most common mechanism of injury is motor vehicle accidents followed by falls, violence, and sporting injuries.
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  Detailed information regarding the mechanism of injury is important and should be sought out by the providing physicians.
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  Specifics, such as the height of the fall or the speed of the collision, provide important clues to amount of force involved and the level of suspicion the clinician should have for a spine injury.
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  Intuitively, the speed and magnitude of the impact correlate with the probability of having an injury.
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Flexion ( http://emedicine.medscape.com/article/824380-overview#aw2aab6b2b3 )
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  Simple wedge compression fracture without posterior disruption: Posterior column remains intact—generally a stable fracture ( Figure 8-3 )
  
  FIGURE 8-3
  
  Image showing an injury, which has both bony and ligamentous instability and high risk for spinal cord injury.
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  Flexion teardrop fracture: Disruption of all three columns—extremely unstable fracture
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  Anterior subluxation: No bony injury but significant displacement can occur with flexion—potentially unstable
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  Bilateral facet dislocation: Extreme form of anterior subluxation—extremely unstable
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  Clay shoveler fracture: Oblique fracture of the base of the spinous process—stable
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  Anterior atlantoaxial dislocation: Unstable
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Flexion-rotation ( http://emedicine.medscape.com/article/824380-overview#aw2aab6b2b4 )
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  Unilateral facet dislocation: Posterior ligament is disrupted but vertebrae are locked in place—stable
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  Rotary atlantoaxial dislocation: Unstable because of location
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Extension ( http://emedicine.medscape.com/article/824380-overview#aw2aab6b2b5 )
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  Hangman’s fracture: Bilateral fractures through the pedicles of C2—unstable
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  Extension teardrop fracture: Displaced anteroinferior bony fragment—unstable
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  Fracture of the posterior arch of C1: Stable but must be distinguished from Jefferson fracture
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  Posterior atlantoaxial dislocation: Unstable
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Axial Compression ( http://emedicine.medscape.com/article/824380-overview#aw2aab6b2b6 )
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  Jefferson fracture: Burst fracture of the ring of C1 ( Figs. 8-4 and 8-5 )—unstable
  
  FIGURE 8-4
  
  CT scan of a Jefferson burst fracture. Axial image through C1 level shows a five-part fracture of the C1 ring. Fractures are minimally displaced, making plain radiographic diagnosis more difficult.
  
  (From Browner BD, Jupiter JB, Levine AM, et al, editors: Skeletal trauma: basic science, management, and reconstruction, ed 4, Philadelphia, 2008, Saunders.)
  
  FIGURE 8-5
  
  Burst-type, true Jefferson fracture. Anteroposterior tomogram shows splaying of the lateral mass of C1.
  
  (From Levine AM, Edwards CC: Treatment of injuries in the C1-C2 complex. Orthop Clin North Am 17:31-44, 1986.)
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  Burst fracture ( Fig. 8-6 ): Disruption of the anterior and middle columns—may be unstable
  
  FIGURE 8-6
  
  Blunt cervical trauma in this 35-year-old man sustained a C7 compressive flexion injury (burst fracture).
  
  (From Browner BD, Jupiter JB, Levine AM, et al, editors: Skeletal trauma: basic science, management, and reconstruction, ed 4, Philadelphia, 2008, Saunders.)
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  Atlas fracture: Unstable because of location
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Complex or Multiple Mechanisms ( http://emedicine.medscape.com/article/824380-overview#aw2aab6b2b7 )
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  Odontoid fracture
  - Type I: Avulsion of the tip of the dens at the insertion site of the alar ligament—mechanically stable but can be associated with atlanto-occipital dislocation
  - Type II: Base of the dens and most common odontoid fractures—unstable ( Fig. 8-7 )
    
    FIGURE 8-7
    
    Subtle type II odontoid fracture. Sagittal CT reformation depicts the horizontal fracture plane at the base of the odontoid process.
    
    (From Browner BD, Jupiter JB, Levine AM, et al, editors: Skeletal trauma: basic science, management, and reconstruction, ed 4, Philadelphia, 2008, Saunders.)
  - Type III: Fracture line into the body of the axis—unstable ( Fig. 8-8 )
    
    FIGURE 8-8
    
    Odontoid fracture with tilt. Open-mouth odontoid view shows a fracture across the base of the odontoid ( arrows ) and lateral tilting of the odontoid process.
    
    (From Browner BD, Jupiter JB, Levine AM, et al, editors: Skeletal trauma: basic science, management, and reconstruction, ed 4, Philadelphia, 2008, Saunders.)
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  Transverse process fracture
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  Complex fracture or fracture-dislocation ( Figs. 8-9 and 8-10 )
  
  FIGURE 8-9
  
  C2-3 fracture subluxation.
  
  FIGURE 8-10
  
  C3-4 spinous fracture and C5 body fracture.
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When to Consult a Specialist

Consultation is not needed for a patient without radiographic abnormality and a normal neurologic examination.

Telephone consultation is appropriate for patients with stable injuries seen on radiographic study and a normal neurologic examination.
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  Isolated single spinous process fractures
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  Small, minimally displaced avulsion fractures
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  Compression fractures with minimal height loss
In-person consultation is indicated for all unstable injures or injuries with associated neurologic deficit.
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  Facet dislocations
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  Vertebral subluxation
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  Vertebral body fractures with spinal canal involvement
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  Unstable ligamentous injury
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  Compression fracture with >25% height loss
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What to Say

When arranging a spine consultation, specific information should be prepared and relayed.
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  Patient’s age and gender
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  Mechanism of injury
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  Physical examination findings
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  Neurologic examination findings
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  Imaging findings
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  Additional injuries
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  Other medical conditions
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Disposition

Patients who can be cleared clinically may be discharged with follow-up with their primary care provider as needed.
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  Activity as tolerated
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  Soft collar for comfort can be used for a short time
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  Pain medications as needed (acetaminophen, nonsteroidal anti-inflammatory drugs [NSAIDs], muscle relaxants, oral narcotics)
Patients with a minor, stable fracture or injury and normal neurologic examination may be discharged from the emergency department after telephone or in-person consultation with a spine specialist. At discharge, specific items should be addressed.
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  Orthotic use as needed
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  Directions for activity
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  Pain management (acetaminophen, NSAIDs, muscle relaxants, oral narcotics)
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  Plan for follow-up with spine specialist (typically 7 to 14 days)
Patients with neurologic findings or unstable injury typically are admitted for traction or operative repair or transferred if definitive care is unavailable.
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Discuss With Patient on Discharge from the Emergency Department
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  With whom and when to follow-up
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  Directions for activity
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  Instructions for orthotic use if indicated
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  Symptomatic and supportive care
  - Pain control (acetaminophen, NSAIDs, muscle relaxants, narcotics)
  - Ice/heat
  - Rest
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  Signs and symptoms of concern
  - Increasing pain
  - Increasing swelling
  - Motor weakness in upper extremities
  - Change in sensation in upper extremities
  - Trouble with speech or breathing
  - Other problems or concerns
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Pitfalls
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  Failure to recognize unstable injuries
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  Failure to recognize associated injuries
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  Failure to consult a specialist from the emergency department for unstable injuries or injuries with associated neurologic findings
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  Failure to recommend follow-up when needed
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  Failure to provide patient with appropriate discharge instructions and medications
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  Stiffness and atrophy from extended, unnecessary cervical collar use
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  Failure to recommend early physical therapy