Ramirez, Elda PhD, RN, FNP-BC, FAANP; Flarity, Kathleen ARNP, PhD, CEN, CFRN, FAEN
CERVICAL SPINE INJURIES can occur anywhere in the cervical spine (C-spine). The upper C-spine consists of the occiput of the head to the second cervical vertebra (i.e., C2). The most common area of cervical injury is the next area, the third cervical vertebra (i.e., C3) to the seventh cervical vertebra (i.e., C7). As many as 75% of patients who sustain traumatic cervical injuries are found to have sustained injuries in this region (Lindsey, Gugala, & Pneumaticos, 2008). Furthermore, 55% of spinal cord injuries are a result of C-spine fracture (Lindsey et al., 2008).
C-SPINE FILMS AND COMPUTERIZED TOMOGRAPHY
An adequate C-spine series includes three views: a true lateral view, which must include all seven cervical vertebrae as well as the C7–T1 junction; an anteroposterior view; and an open-mouth or odontoid view (Duane et al., 2008; Edwards, 2001; Graber, 1999; Mower, 2001). Refer to Part I: “Introduction to Reading and Clearing Cervical Spines for Advanced Practice Nurses” for specific details on reading and clearing cervical spines.
If there is any suspicion that an abnormality exists on the plain radiograph or if the patient has any midline tenderness that seems to be disproportionate to the findings on plain films, computed tomography (CT) scan of the area in question should be obtained. Currently, however, controversy exists in relation to beginning with CT scan as opposed to beginning with a plain C-spine films.
In 2006, Plantzer et al. found that the cervical CT scan was a more “efficient” tool to detect skeletal injury. The outcome of the study identified 100% sensitivity with CT scan as opposed to 63% sensitivity with cross-table lateral plain film. In 2008, a study of 1,004 patients with blunt trauma from February of 2004 to September of 2006 who had a lateral C-spine and CT scans of the neck found that 84 had C-spine fractures, and of those who were identified by CT scan, 68 had negative or incomplete lateral C-spine films (Duane et al., 2008). The authors of the study recommended to the American College of Surgeons that the lateral film be eliminated from the curriculum of Advanced Trauma Life Support and that CT scan of the neck be the gold standard for evaluation of the neck in blunt trauma (Duane et al., 2008).
Therefore, there is some consensus that CT imaging should be performed in all trauma patients with suspected C-spine injury. The study of plain films versus CT scan for C-spine evaluation has been ongoing since the late 1980s and many facilities now have protocols that initiate the CT scan of the spine as first-line imaging for the posttrauma patient with suspected injury of the C-spine. Magnetic resonance imaging (MRI) is still recommended for suspicion of ligamentous injuries of the C-spine.
SELECTED C-SPINE INJURIES
There are several types of C-spine injuries. The mechanism of injury and whether the injury is stable or unstable affects the immediate and long-term management of the patient. The etiology of C-spine injury ranges from sports injuries to motor vehicles, but in the elderly population, a simple fall from standing can cause a severe, life-altering cervical injury (Hertner & Stewart, 2008). The diagnosis of a C-spine injury can be identified by the mechanism of injury, a thorough evaluation of medical history, clinical assessment, and radiographic imaging. The mechanism can be deductively assumed on the basis of the history and mechanism, such as flexion, extension, rotation, and axial compression (Table 1). For example, in a head-on motor vehicle crash, there may be a flexion–extension injury of the C-spine, whereas in a lateral collision (i.e., T-bone mechanism), there may be rotation involved in the flexion and extension of the C-spine. These mechanisms attribute to the potential for certain significant fracture or ligamentous injury. These presentations can be either stable or unstable. The most common types of mechanisms along with the clinical presentations, diagnosis, and management for patients for these selected cervical injuries discussed herein in Part II are as follows: (1) teardrop fracture, (2) hangman's fracture, (3) burst fracture, (4) Jefferson burst fracture, (5) odontoid (dens) fracture, (6) anterior wedge compression fracture (7) clay-shoveler's fracture, and (8) unilateral facet dislocation (stable) with fracture and bilateral facet dislocation (unstable) with fracture.
Teardrop Fracture (Unstable)
The flexion or teardrop fracture is an unstable fracture. This fracture is a triangular fracture fragment located at the anteroinferior corner of a cervical vertebral body (Greenberg, 2004; Kim, Chen, Russell, & Rogers, 1989). Flexion teardrop fractures result from forceful hyperextension and compression applied to the anterior C-spine when the flexed head strikes an object such as what happens in a diving accident.
Teardrop fractures involve a disruption of all three spinal columns, including the anterior longitudinal ligament, posterior longitudinal ligament, and facet joints, making this an extremely unstable fracture (Davenport, Mueller, & Belaval, 2008). In addition to the characteristic anteroinferior fracture, disruption of the anterior longitudinal ligament and interverterbral disk may occur. Equal and opposite posterior forces may lead to disruption of the posterior longitudinal ligament and facet joints. Posterior displacement of the vertebral body may result in compression of the anterior columns of the spinal cord and may be associated with substantial neurologic deficits (Davenport et al., 2008).
Patients with flexion teardrop fractures present after trauma with localized or generalized neck pain. Paresthesias, paresis, or paralysis may also be present in patients with flexion teardrop fractures (Kim et al., 1989).
A flexion teardrop fracture usually is obvious on plain radiographs, which demonstrate the anteroinferior teardrop fragment, posterior displacement of the vertebral body into the spinal canal, bilateral subluxation or dislocation of the facet joints, and widening or “fanning” of the interspinous spaces (Fig 1; Graber, 1999; Greenberg, 2004; Kim et al., 1989).
CT scan or MRI may be needed to fully define and delineate ligamentous or spinal cord injury. Physical examination may reveal tenderness on palpation of the midline C-spine, as well as findings consistent with anterior cord syndrome. This syndrome is characterized by loss of motor function below the level of the location of injury. There is also loss of sensation (i.e., pain and temperature), but fine touch and proprioception are preserved. Death from diaphragm paralysis is possible if the cervical cord injury is located high enough. Typically, patients with anterior cord syndrome will have a loss of pain, temperature, and some touch sensation, combined with preservation of the posterior column functions, which include position, motion, and vibratory senses (Greenberg, 2004; Kim et al., 1989).
A flexion teardrop fracture is considered to be severely unstable. Strict C-spine immobilization is paramount. Emergency consultation with a neurosurgeon or orthopedic surgeon for spinal cord decompression, external immobilization, and eventual spinal fusion should be initiated as soon as possible. The use of steroids in any case of spinal trauma remains controversial (Greenberg, 2004; Kim et al., 1989).
Hangman's Fracture (Unstable)
Hangman's fracture, also known as traumatic spondylothesis of the axis, is a bilateral fracture of the pars interarticularis of the second cervical vertebrae (C2). The fracture line passes through the posterior elements, more specifically between the superior and inferior articular facets of C2 (Fig 2; Neurosurgery, 2002).
Patients with a hangman's fracture present with neck pain after an injury involving forced extension of the C-spine. Judicial hangings, for which this fracture is named, result in hyperextension and fracture. However, hangman's fractures more commonly are the result of motor vehicle crashes. These injuries produce the same fracture pattern through hyperextension and compression (Davenport et al., 2008). Other inciting injuries, such as falls, pedestrians struck by vehicles, or high-speed motor vehicle collisions, commonly have high-energy mechanisms (Davenport et al., 2008; Neurosurgery, 2002; Ryan & Henderson, 1992). On physical examination, cervical tenderness is generally present. Patients may manifest with neurological deficits, depending on the severity of vertebral displacement and the presence of other C-spine fractures.
Plain C-spine radiographs, including lateral, anteroposterior, and odontoid views, should be obtained to confirm the diagnosis, although the lateral view is most often diagnostic. Radiographically, a fracture line should be evident, extending through the pedicles of C2 along with obvious disruption of the spinolaminar contour line (Davenport et al., 2008).
CT scanning may be helpful to delineate the precise pattern of bony injury and to visualize any possible intrusion into the spinal canal, indicating spinal cord involvement (Neurosurgery, 2002; Ryan & Henderson, 1992).
Cervical immobilization is essential throughout the patient's emergency department course. Advanced trauma life support with adherence to airway, breathing, and circulation (i.e., ABCs) should be followed because hangman's fractures have been identified in patients with multisystem trauma (Neurosurgery, 2002). Consultation with a neurosurgeon or an orthopedic surgeon for management is indicated. Although considered an unstable fracture, this fracture seldom is associated with a spinal cord injury because the anteroposterior diameter of the spinal canal is greatest at this level and the fractured pedicles allow for decompression in this region. When associated with unilateral or bilateral facet dislocation at the level of C2, this particular type of hangman's fracture is unstable and has a high rate of neurological complications that require immediate referral to reduce facet dislocation. Long-term management includes stabilization with a rigid cervical collar or a halo immobilization device. Surgical fusion is performed in cases where there are severe cervical angulations, disruption of the C2-C3 disk space, and/or failure of external immobilization to maintain fracture alignment (Davenport et al., 2008).
Burst Fracture (Unstable)
A cervical burst fracture is a compression of the vertebral body and results in loss of both anterior and posterior vertebral body height. This is unlike the wedge fracture in which there is loss of only anterior vertebral body height. Bony fragments may push on the spinal cord and cause symptoms. This type of fracture is most common in the mid C-spine.
A burst fracture is typically caused by a downward compressive force from a vertical compression mechanism. When downward compressive force is transmitted to lower levels in the C-spine, the body of the cervical vertebra can shatter outward, causing a burst fracture. Patients present with neck pain after an injuring involving axial loading of the cervical spine. Associated neurologic complaints such as focal weakness, paralysis or paresthesia may also be present (Neurosurgery, 2002).
Radiographically, a burst fracture is evidenced by a vertical fracture line in the frontal projection and by communition and protrusion of the vertebral body anteriorly and posteriorly with respect to the contiguous vertebrae in the lateral view (Fig 3). Posterior protrusion of the middle column may extend into the spinal canal and can be associated with anterior cord syndrome. Burst fractures require an axial CT scan or MRI to document the amount of middle column retropulsion (i.e., a pushing back that portion of the C-spine; Davenport et al., 2008).
Consultation with a neurosurgeon or orthopedic surgeon for management and ongoing care is indicated. Initial management of burst fractures with a loss in height of more than 25%, retropulsion, or neurologic deficit is accomplished by applying traction with cervical tongs. When none of those problems exist, the fracture is considered stable (Davenport et al., 2008).
Jefferson Burst Fracture (Unstable)
A Jefferson burst fracture consists of at least two fractures of C1 (ring structure). It is a combination of an anterior and posterior fracture of the atlas or C1 (Figs 4 and 5). The Jefferson fracture most commonly occurs as the result of axial loading on the head through the occiput, leading to a burst-type fracture of C1. For example, a Lifesaver candy is difficult to break in only one spot. Similarly, in the C-spine, vertical compression forces are transmitted through the skull to the occipital condyles and onto the superior articular facets of the lateral masses of C1. The occipital condyles are downward sloping and act as a wedge to drive apart the ring-shaped atlas. The process displaces the masses laterally and causes fractures of the anterior and posterior arches, along with possible disruption of the transverse ligament. A “quadruple” fracture, in of all four aspects of the C1 ring occurs with this type of fracture (Foster, 2006; Hadley, Walters, & Grabb, 2002; Neurosurgery, 2002). Fractures of the atlas (C1) comprise 25% of atlantoaxial complex bony injuries, 10% of C-spine injuries, and 2% of all spine injuries (Foster, 2006).
Patients with Jefferson burst fractures present with neck pain after an injury involving axial loading of the C-spine. Axial injuries can occur when a heavy object falls on the head of an individual or when an individual dives into a shallow pool. Diving is the most frequent mechanism, with resultant striking of the head on an obstacle in shallow water. The next most frequent cause of this fracture is being thrown up against the roof of a motor vehicle. Forces are distributed to the body through the neck. The next most frequent cause of this type of cervical injury is from a fall onto the head (except in toddlers, who are predisposed to injury from falls because of their disproportionate head size; Foster, 2006; Hadley et al., 2002; Neurosurgery, 2002). A patient with a Jefferson burst fracture may also have associated neurologic complaints, such as focal weakness, paralysis, or paresthesias. On physical examination, midline cervical tenderness usually is present.
Plain C-spine radiography usually is adequate to confirm this diagnosis. Obtain lateral, anteroposterior, and odontoid radiographs. The open-mouth odontoid view is the best projection to identify a Jefferson fracture. C1 lateral masses slip laterally and are no longer flush at the edges of C2; predental space is more than 3 mm (Fig 5). If displacement of the lateral masses is more than 6.9 mm, complete disruption of the transverse ligament has occurred and immediate referral for cervical traction is warranted. If displacement is less than 6.9 mm, the transverse ligament is still competent and neurologic injury is unlikely (Foster, 2006; Graber, 1999).
Jefferson burst fractures are seen in patients with multisystems trauma. As with all trauma patients, initial clinical evaluation begins with a primary survey, focusing on life-threatening conditions. Assessment of airway, breathing, and circulation takes precedence while concurrently considering C-spine injury (Hadley et al., 2002). Refer to Part I, for history and physical examination. Provide C-spine immobilization with a rigid cervical collar. If an abnormality is identified on the plain radiograph, a computed tomography scan is recommended to delineate the precise patterns of injury. MRI is for diagnosing ligamentous disruption and associated spinal instability (Hadley et al., 2002). Consultation with a neurosurgeon or orthopedic surgeon for management and ongoing care is indicated.
Odontoid Fractures or Dens Fractures (Unstable)
Odontoid or dens fractures are C2 fractures (Table 2). Dens fractures account for almost 60% of all axis fractures and 10%–18% of all C-spine fractures (Sasso, 2001). They can result from acute traumatic flexion and extension. In flexion injuries, anterior displacement of the dens may occur, whereas in extension injuries, posterior displacement is more commonly seen.
There are three classes of odontoid fractures, the most unstable of which is type II. Figure 5 illustrates type I, II, and III dens fractures (An, 1998; Sasso, 2001; Table 2).
A type I odontoid fracture is an avulsion of the superior tip of the odontoid. The transverse ligament remains intact, and the fracture is mechanically stable; however, it is often seen in association with atlanto-occipital dislocation and must be ruled out because of this potentially life-threatening complication.
Type II fractures occur at the base of the dens and are the most common odontoid fractures. This type of fracture is associated with a high prevalence of nonunion due to the limited vascular supply and small area of cancellous bone (Figs 5 and 6).
A type III odontoid fracture occurs when the fracture line extends into the body of the axis. Nonunion is not a major problem with this type of injury because of a good blood supply and the greater amount of cancellous bone.
Patients with dens fractures present after blunt trauma, multidirectional, and hyperflexion/extension injuries. Patients typically complain of neck pain if they are awake. Patients may also report neurological deficits such as tingling, numbness, loss of sensation (i.e., paresthesias), or even loss of motor function (i.e., paralysis; An, 1998; Sasso, 2001).
The diagnosis of C1 and C2 is made by first examining the lateral aspects of C1 on the plain radiograph. The lateral aspects should be symmetric, with an equal amount of space on each side of the dens. Any asymmetry is suggestive of a fracture. The lateral aspects of C1 should also line up with the lateral aspects of C2. If these areas do not line up, there may be a fracture of C1. Figure 5 demonstrates asymmetry in the space between the dens and C1, as well as displacement of the lateral aspects of C1 laterally. Often, teeth may give the appearance of a fracture (either longitudinal or horizontal) through the dens. However, fractures of the dens are unlikely to be longitudinally oriented. If there is any question of a fracture, the film should be repeated in an attempt to move the teeth out of the film. If it is not possible to exclude a fracture of the dens, thin-section CT scans or plain film tomography is indicated (Graber, 1999).
The diagnosis of an odontoid fracture can be identified with the standard 3-view radiographs. The open-mouth odontoid view is the favored view to diagnose most odontoid fractures. However, helical CT scan may be necessary if plain radiographs are inconclusive. Look at the open-mouth view for a black line in the odontoid process, which would represent a fracture.
Treatment modalities depend on the grade of the fracture. A type I dens fracture requires external immobilization with a halo vest for up to 12 weeks (An 1998, Sasso 2001). Type II and III dens fractures are preferably managed nonoperatively. However, in cases where there is displacement greater than 6 mm, a neurologic deficit in the patient, continued ventilator-dependence, or nonunion of the cervical fracture after nonoperative management, patients must be managed surgically (Sasso, 2001).
Anterior Wedge Compression Fracture (Stable)
An anterior wedge fracture is a fracture that occurs when there is compression between two “wedges” of the C-spine (Ma, Cline, Tintinalli, Keken, & Stapczynski, 2004; Zdeblick, 2009; Fig 7). It occurs when there is axial load flexion (e.g., football player or diver) on the C-spine (Gable & Nunn, 2008; Vaccaro, 2002). An anterior wedge fracture is considered stable when compression is less than 50%, angulation is less than 30%, and the posterior elements such as the posterior portion of the vertebrae remain intact (Gable & Nunn, 2008; Vaccaro, 2002).
Prevertebral soft tissue swelling may be evident in patients with anterior wedge fractures and they may have no deficit. Therefore, there should always be a high index of suspicion for patients who sustain axial loading flexion and/or hyperflexion injuries. Trauma patients with these mechanisms of injury should always be evaluated for this type of compression fracture.
Anterior wedge compression fractures are best identified on lateral radiographic films, which demonstrate both an anterior compression and an intact posterior cortex (Kaji & Hockenberger, 2009). A CT scan or MRI should also be performed on patients with this type of injury to confirm that there is no posterior involvement, soft tissue trauma, and/or hematoma. These findings then make this fracture an unstable one. This fracture may result in a neurologic deficit in the patient (Kaji & Hockenberger, 2009; Ma et al., 2004; Zdeblick, 2009).
Patients with anterior wedge compression fractures should be placed in a rigid cervical collar. Rigid collars are recommended for simple wedge fractures without ligamentous injury and include bed rest along with the hyperextension of the vertebral body (Bongard & Sue, 2002; Zdeblick, 2009). It is important to consult with a spine specialist to concur on treatment based on the degree of compression less than 50% and its management and activity constraints.
Clay-Shoveler's Fracture (Stable)
A clay-shoveler's fracture occurs when there is intense flexion against a tightened trapezious and/or rhomboid muscles during heavy work (Dutton, 2008; Ma et al., 2004). This injury is common usually in ditchdiggers and power lifters and was historically identified in Englishmen who dug heavy clay for hours (Dutton, 2008). In recent time, this injury is identified in patients involved in motor vehicle collisions with sudden deceleration (Kaji & Hockenberger, 2009).
The patient will complain of sudden, sharp neck, shoulder, and arm pain. The neck pain is usually felt at C7. There will be a C6 or C7 nondisplaced spinal process fracture noted on the plain film (Zdeblick, 2009). This is the result of an avulsion of the supraspinadus ligament. This ligament has been pulled off the spinous process of C6 or C7 (Zdeblick, 2009; Fig 8)
A lateral view is the one view that captures this fracture best because it is usually nondisplaced (Gable & Nunn, 2008). Further radiographic testing is not necessary if there is no indication clinical assessment.
Initially, the provider must establish stability of the fracture with assessment and radiography. The clay-shoveler's fracture, when isolated, can be treated nonoperatively (Wheeless, 2009). The recommendation is a rigid collar for 10 days but if flexion/extension films are difficult to obtain, the patient should be maintained in a collar until there is callous formation (Wheeless, 2009).
Unilateral Facet Dislocation (Stable) With Fracture and Bilateral Facet Dislocation (Unstable) With Fracture
A bilateral facet dislocation is caused by a flexion force that extends anteriorly. This dislocation results in an injury to the disk and anterior longitudinal ligament of the C-spine. There is a resultant anterior displacement of the spine that is greater than 50% of the anterior/posterior diameter of the width of the spine (Brunicardi, 2005). This is a highly unstable fracture that usually involves complete spinal cord injury.
The critical assessment for a patient with this presentation is spinal shock. If the patient is unconscious and unable to communicate neck pain, this injury may not be identified on plain films. Hemodynamic monitoring and neurologic assessment of these patients are critical.
This bilateral facet injury is diagnosed by the lateral cervical view of the plain radiograph. The diagnosis of a unilateral facet dislocation is based on anteroposterior and lateral plain film view or CT scan. The lateral view will show less than 50% anterior displacement of the width of the vertebrae and the anteroposterior view will show the rotation, and the processes will be pointing to the side of dislocation (Brunicardi, 2005).
A unilateral facet dislocation is a stable injury if there are no fractures involved. The dislocation takes place after a flexion rotation at the contralateral facet joint. The posterior ligament is affected but the spinal cord is not commonly injured unless fracture is present. The nonsurgical management of facet dislocation is reduction with traction. It is imperative that an MRI is performed initially, especially in the bilateral facet dislocation, because the cord injury may be extensive (Wheeless, 2009). A ventral surgical approach is common with facet dislocation, and in this approach, it is less likely to have retrograde disk compression postreduction (Ordonez, Benzel, Naderi, & Weller, 2000; Figs 9 and 10).
TRAUMA CENTER REFERRAL
Trauma designation of the facility you work in, at least in the United States, which may differ in other countries, is a guide to what methods of consultation and transfer are necessary for a patient with C-spine injury. A level IV trauma facility transfer must be initiated immediately when the provider becomes aware of neurologic deficit, spinal injury or fracture and/or the injury or fracture cannot be ruled out due to limited radiographic capabilities at these sites. A level III trauma facility usually does not have appropriate referral/consultation in neurosurgery; so, transfer must be initiated immediately. A level II trauma facility should have the capability (neurosurgery/orthopedic spine provider) to manage a C-spine injury/fracture. C-spine-injured patients should receive level I trauma care whether it is available at the time of injury or immediately thereafter. A neurosurgeon or orthopedic spine specialist should be consulted immediately to assume the care of this patient. If the provider is not at a facility that can manage these patients, they must be trained not only to manage neurogenic shock and other sequelae of spinal injury but also to be skilled at transfer management for their service areas. Providers must always keep in mind that whether the patient is awake or unconscious or whether the mechanism may not seem severe, C-spine injuries are not always identified with plain radiographs and neurologic deficit is not always present immediately after injury. The consultant should make final diagnostic decisions with regard to C-spine injury.
In sum, practitioners have an enormous responsibility in the management of emergency department patients with suspected cervical injuries. It is critical that practitioners manage their patients comprehensively. The Emergency Nurses Association's “Competencies for Nurse Practitioners in Emergency Care” lists “clinically assesses and manages C-spine” as one of its competencies (Emergency Nurses Association, 2008). The goal in evaluating the C-spine is to recognize any unstable injury, whether it be bony or ligamentous or whether there is an actual spinal cord injury. Evaluation of the patient with suspected C-spine injury can be challenging for providers. A systematic, thorough approach with meticulous attention to detail will prevent errors in interpretation and diagnosis. Using evidence-based practice tools such as the Canadian C-spine Rule (CCR) and the National Emergency X-Radiography Utilization Study (NEXUS) criteria may allow the provider to clear C-spines clinically without radiographs. Practitioners must recognize that in certain cases, the C-spine cannot be “cleared” in the emergency department setting. Finally, practitioners in the emergency department should be evaluated for competency at least yearly for C-spine clearance, assessment, and management of patients with C-spine injuries.