Chapter 24: Thoracolumbar Spine Fractures

Peter O. Newton, Scott J. Luhmann

Chapter Outline

Introduction to Thoracolumbar Spine Fractures

Fractures of the thoracic and lumbar spine in pediatric patients are relatively uncommon compared with those in adult patients.33,68 Although cervical spine injuries outnumber thoracic and lumbar spinal column injuries, fractures of the thoracolumbar region are certainly not rare. The mechanisms of injury vary with age,16,69 whereas the classification of these injury patterns follow adult spine fracture guidelines. These fractures can be broadly grouped as compression, burst, flexion–distraction, and fracture-dislocations. The treatment principles are based on the mechanism of injury and the “stability” of the fracture. 
Clarifying the stability of any given fracture can be challenging, and controversy remains as to how to establish which fractures require surgical stabilization. The status of the neurologic system is an important variable in treatment.3,24 In addition, other associated injuries are common,5 particularly with flexion–distraction “lap belt” injuries.31,36,47,51,65 Understanding the mechanism of injury, the neurologic status and associated injuries will allow logical decision making about the treatment approach to a pediatric patient with thoracolumbar spinal injury. 
The goals of treatment for all spinal injuries are to maximize the potential for recovery of spinal cord function if a spinal cord injury (SCI) was present and/or to provide skeletal stability to the spinal column to protect against future SCI. These two goals may be analyzed separately when both instability and SCI exist. Optimizing return of any lost spinal cord function is paramount, and the potential for recovery of spinal cord function in general is greater in children than in adults.24,83 

Assessment of Thoracolumbar Spine Fractures

Mechanisms of Injury of Thoracolumbar Spine Fractures

One of the most important aspects of treating thoracolumbar spinal fractures is understanding the mechanism of injury. In general, the mechanism of injury correlates with the age of the patient.16 Spine trauma, just like appendicular trauma, should generate concern for nonaccidental injury in infants and young children.12,18,42 Levin et al.48 reported on seven unstable thoracolumbar spinal fractures in abused children. 
Motor vehicle accidents may be the most common cause of spinal column injury in all age groups.5 The type of seat belt restraint has clear implications in the mechanism of force transfer to the spine, with the lap belt a common cause of both intra-abdominal and spinal injuries.31,47,65,70,76 The lap belt has been long known to create hyperflexion of the trunk over the belt with the spine pinching the intra-abdominal organs anteriorly. The point of flexion is anterior to the spine leading to anterior compression combined with posterior column distraction (Fig. 24-1). Addition of a shoulder strap or child seat with a full frontal harness limits flexion with frontal impact accidents and protects the spine (and other parts of the body) from injury. 
Figure 24-1
A lap belt used for a child can create a point of rotation about which the spine is flexed with an abrupt stop.
 
This is a common mechanism for creating both intra-abdominal and flexion–distraction spinal injuries.
This is a common mechanism for creating both intra-abdominal and flexion–distraction spinal injuries.
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Figure 24-1
A lap belt used for a child can create a point of rotation about which the spine is flexed with an abrupt stop.
This is a common mechanism for creating both intra-abdominal and flexion–distraction spinal injuries.
This is a common mechanism for creating both intra-abdominal and flexion–distraction spinal injuries.
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Falls from a height generally result in axial loading of the spine, which may result in a “burst” fracture or wedge compression fracture, depending on the degree of flexion of the trunk at the time of impact. These fracture patterns are possible with any mechanism associated with axial compression and can occur with motor vehicle accidents and sporting injuries.16 Compression of the vertebra with the trunk flexed creates the greatest forces in the anterior aspect of the vertebra, leading more commonly to anterior column wedging. This is in contrast to the trunk in an extended position, which loads the vertebral body more symmetrically. Fractures in this case often collapse with radial expansion or “bursting.” Displacement of the posterior vertebral body fragments into the spinal canal may cause injury or compression of the neurologic elements (spinal cord or cauda equina).34 
If the magnitude of injury sustained seems out of proportion to the force applied, the possibility of an insufficiency fracture due to weak bone should be considered. Osteoporotic insufficiency fractures, common in the elderly, are rare in children; however, several disease states may predispose children to these fractures. Chronic corticosteroid use associated with the management of many pediatric rheumatologic and cancerous diseases often leads to osteoporosis and increased risk of compression fractures.80 In addition, primary lesions of the bone, such as Langerhans histiocytosis, often affects thoracic vertebrae.4,25 Other tumors and infections warrant consideration when nontraumatic compression fractures are identified.54,67 

Associated Injuries with Thoracolumbar Spine Fractures

Just as the mechanism of injury should raise suspicion of a particular injury (e.g., lap belt injury and flexion–distraction lumbar fracture pattern), so should the presence of one injury raise suspicion of a concomitant associated injury. First, any spinal fracture should be considered a significant risk factor for a spinal fracture at another level.50 The traumatic force required to create one fracture is often enough to result in one or more additional fractures at other locations. Similarly, a cervical injury is frequently associated with closed head injury and vice versa. 
The lap belt mechanism of injury is well known to create flexion–distraction injuries of the spine, but also is associated with intra-abdominal injury.65 Compressed between the seat belt and the spinal column, the aorta, intestinal viscera, and abdominal wall musculature are at risk for laceration. Abdominal injuries are present in almost 50% of pediatric patients with Chance fractures.56 Ecchymosis on the anterior abdomen is suggestive of intra-abdominal injury that warrants further evaluation with laparoscopy, laparotomy, or additional imaging by computed tomography (CT).5,76 A high index of suspicion is required, because missed injuries may be life-threatening.47 
Associated injury to the spinal cord has obvious significance and may be present with many fracture patterns. Disruption of the stability of the spinal column or bony intrusion into the spinal canal may result in compromise of neurologic function. All patients with a known spinal column fracture or dislocation warrant a careful neurologic examination. Overall, most pediatric patients with thoracolumbar fractures are neurologically intact (85%), and less commonly present with SCIs (incomplete in 5% and complete in 10%).20 Similarly, patients with a traumatic neurologic deficit require a careful evaluation of the spinal column integrity. There are, however, a subset of patients who present with SCI without radiographic abnormality.57,58 This scenario has been termed SCIWORA, a phenomenon much more common in children than adults. It is thought that the flexibility of the immature spine allows spinal column segmental displacements great enough to lead to SCI without mechanically disrupting the bony and/or ligamentous elements.57 Although these injuries may not be visible on plain radiographs, nearly all will have some evidence of soft tissue injury of the spine on more sensitive magnetic resonance imaging (MRI) studies.29 The term SCIWORA is less relevant in the era of routine MRI, which is now obtained in all patients with possible SCI39 and some have suggested a new acronym SCIWONA (SCI without neuroimaging abnormality).79,90 

Signs and Symptoms of Thoracolumbar Spine Fractures

Careful evaluation of a patient with a potential traumatic spinal injury begins as with any serious trauma victim. The ABCs of resuscitation (airway, breathing, circulation) are performed while maintaining cervical and thoracolumbar spinal precautions. The frequency of spinal injuries in the setting of major trauma (motor vehicle accident, fall, etc.) is particularly high. After stabilizing the cardiorespiratory systems, symptoms of pain, numbness, and tingling should be sought if the patient is old enough and alert enough to cooperate. Pain in the back is often not appreciated when other distracting injuries exist and the patient is immobilized on a backboard. Examination of the back must not be forgotten and is performed by logrolling the patient. Visual inspection, along with palpation, should seek areas of swelling, deformity, ecchymosis, and/or tenderness that may provide a clue to the presence of an injury. In trauma patients, thoracolumbar fractures are more common in older children and adolescents, and there is a low mortality rate and infrequent need for operative stabilization.71 Clinically the ability to diagnosis a thoracolumbar spine fracture in pediatric trauma patients has been demonstrated to have good sensitivity and average specificity.37 Hence routine screening radiographs of any patients suspected of having a thoracolumbar spine injury should be performed, to minimize the likelihood of missing an injury. 
Neurologic examination provides information on the integrity of the spinal cord. The age of the patient may limit the thoroughness of this assessment, but some indication of sensory and motor function should be sought. In cases of spinal cord deficit, a detailed examination of the strength of each muscle group, sensory levels, and rectal tone will need to be serially compared over time and the quality of the documentation cannot be overemphasized. The prognosis for recovery is significantly better if the SCI is incomplete.13,32,83 The status of the neurologic function over time may lead to important treatment decisions regarding the necessity and timing of surgical intervention. A progressive neurologic deficit warrants immediate surgical attention, whereas an improving status may suggest a less urgent approach. Overall, the physical examination has a sensitivity of 87% in identifying thoracolumbar fractures.71 

Imaging and Other Diagnostic Studies for Thoracolumbar Spine Fractures

Following a careful clinical examination of all patients with a suspected spinal injury, plain radiographs are usually valuable. An alert, cooperative patient without pain or tenderness in the back can be cleared without radiographs. However, any patient with a significant mechanism or associated injury (motor vehicle accident, fall from greater than 10 ft, major long-bone fracture, cervical or head injury) requires thoracolumbar spine radiographs if they have spinal tenderness, are obtunded, or have a distracting injury. Initial films should include supine anteroposterior (AP) and lateral views of the thoracic and lumbar spine. In addition, because of the strong association between cervical spine fractures and thoracolumbar spine fractures after blunt vehicular trauma, routine imaging of the complete spine when a cervical fracture is identified is indicated.87 
Plain radiographs often show relatively subtle findings that should be sought in all cases. On AP radiographs, soft tissue shadows may be widened by paravertebral hematoma. The bony anatomy is viewed to evaluate for loss of height of the vertebral body as compared with adjacent levels. Similar comparisons can be made with regard to interpedicular distance and interspinous spacing.10 Lateral radiographs give important information about the sagittal plane: Anterior vertebral wedging or collapse or posterior element distraction or fracture. Careful scrutiny of the plain radiographs is always prudent; however, the CT scan will nearly always be used to clarify any suspected fractures. Antevil et al.1 reported the sensitivity of plain radiographs to be 70% (14 of 20 patients) for spine trauma, whereas the sensitivity was 100% for CT scanning (34 of 34 patients). 
CT is now a standard component of the evaluation of many trauma patients. Multidetector scanners allow rapid assessment with axial, coronal, and sagittal images for patients with plain radiographic abnormalities. The axial images are best for evaluating the integrity of the spinal canal in cases of a burst fracture, whereas the sagittal views will demonstrate vertebral body compression as well as posterior element distraction or fracture. In addition, major dislocations easily seen on plain radiographs will be better understood with regard to the space left in the spinal canal for the neurologic elements. The amount of spinal canal compromise has been correlated with the probability of neurologic deficit.55 
MRI is the modality of choice for evaluating the discs, spinal cord, and posterior ligamentous structures.39,46,77 Although more difficult to obtain in a multiply injured patient, this study is mandatory in patients with a neurologic deficit to assess the potential cause of cord dysfunction. The MRI is able to distinguish areas of spinal cord hemorrhage and edema. Assessment of the posterior ligamentous complex (PLC) is critical in differentiating stable and unstable burst fractures, as well as compression fractures and flexion–distraction injuries. Although subject to overinterpretation, MRI has been shown to modify the diagnosis made by plain radiographs and CT and correlates very well with intraoperative findings of the structural integrity of the posterior soft tissues.46,62 

Classification of Thoracolumbar Spine Fractures

There are several methods of classifying thoracolumbar fractures: Holdsworth—two column, Denis—three column,17 McCormack—load sharing,53 Gertzbein—comprehensive,27 Thoracolumbar Injury Classification and Severity Score,61 each with purported advantages. Designed primarily with the adult spine fracture patterns in mind, the Denis classification translates well for the categorization of most pediatric thoracolumbar injuries.44 Based on theories of stability related to the three-column biomechanical concept of the spine (anterior, middle, posterior columns), the Denis classification in its simplest form includes compression, burst, flexion–distraction, and fracture-dislocations (Fig. 24-2). 
Figure 24-2
Denis classification of thoracolumbar fractures.
 
A: Compression fracture: This injury results in mild wedging of the vertebra primarily involving the anterior aspects of the vertebral body. The posterior vertebral height and posterior cortex remain intact. B: Burst fracture: A burst fracture involves both the anterior and middle columns with loss of height throughout the vertebral body. There may be substantial retropulsion of the posterior aspect of the vertebra into the spinal canal. In addition, posterior vertebral fractures and/or ligamentous injury may occur. C: Flexion–distraction injuries: This fracture, which occurs commonly with a seat belt injury mechanism, results in posterior distraction with disruption of the ligaments and bony elements of the posterior column, commonly extending into the anterior columns with or without compression of the most anterior aspects of the vertebra. D: Fracture-dislocation: These complex injuries involve marked translation of one vertebra on another with frequently associated SCI as a result of translations through the spinal canal.
A: Compression fracture: This injury results in mild wedging of the vertebra primarily involving the anterior aspects of the vertebral body. The posterior vertebral height and posterior cortex remain intact. B: Burst fracture: A burst fracture involves both the anterior and middle columns with loss of height throughout the vertebral body. There may be substantial retropulsion of the posterior aspect of the vertebra into the spinal canal. In addition, posterior vertebral fractures and/or ligamentous injury may occur. C: Flexion–distraction injuries: This fracture, which occurs commonly with a seat belt injury mechanism, results in posterior distraction with disruption of the ligaments and bony elements of the posterior column, commonly extending into the anterior columns with or without compression of the most anterior aspects of the vertebra. D: Fracture-dislocation: These complex injuries involve marked translation of one vertebra on another with frequently associated SCI as a result of translations through the spinal canal.
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Figure 24-2
Denis classification of thoracolumbar fractures.
A: Compression fracture: This injury results in mild wedging of the vertebra primarily involving the anterior aspects of the vertebral body. The posterior vertebral height and posterior cortex remain intact. B: Burst fracture: A burst fracture involves both the anterior and middle columns with loss of height throughout the vertebral body. There may be substantial retropulsion of the posterior aspect of the vertebra into the spinal canal. In addition, posterior vertebral fractures and/or ligamentous injury may occur. C: Flexion–distraction injuries: This fracture, which occurs commonly with a seat belt injury mechanism, results in posterior distraction with disruption of the ligaments and bony elements of the posterior column, commonly extending into the anterior columns with or without compression of the most anterior aspects of the vertebra. D: Fracture-dislocation: These complex injuries involve marked translation of one vertebra on another with frequently associated SCI as a result of translations through the spinal canal.
A: Compression fracture: This injury results in mild wedging of the vertebra primarily involving the anterior aspects of the vertebral body. The posterior vertebral height and posterior cortex remain intact. B: Burst fracture: A burst fracture involves both the anterior and middle columns with loss of height throughout the vertebral body. There may be substantial retropulsion of the posterior aspect of the vertebra into the spinal canal. In addition, posterior vertebral fractures and/or ligamentous injury may occur. C: Flexion–distraction injuries: This fracture, which occurs commonly with a seat belt injury mechanism, results in posterior distraction with disruption of the ligaments and bony elements of the posterior column, commonly extending into the anterior columns with or without compression of the most anterior aspects of the vertebra. D: Fracture-dislocation: These complex injuries involve marked translation of one vertebra on another with frequently associated SCI as a result of translations through the spinal canal.
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Compression fractures are the most common thoracolumbar spine fracture pattern.11,35 The vertebral body loses height anteriorly compared with the posterior wall. The anterior aspect of the vertebral body is involved, but the posterior wall of the vertebral body is by definition intact. Axial load with flexion is the common mechanism. Depending on the degree and direction of flexion, the wedging may vary between the coronal and sagittal planes (Fig. 24-3). The percentage of lost height defines the severity of compression fractures, which rarely have an associated neurologic deficit. However, the fractures are often associated with similar or occasionally more severe fractures at adjacent or distant levels. Contiguous compression fractures, each of a modest degree, together may result in a substantial kyphotic deformity. Because the cause of these injuries, such as a fall, is fairly common, it is at times necessary to determine if a wedged vertebra seen radiographically represents an acute compression fracture, sequelae of Scheuermann kyphosis, or a remote injury. Clinical examination can localize pain to the site of the fracture in acute injuries; however, MRI or bone scanning can confirm acute fracture based on signal changes and increased isotope uptake. 
Figure 24-3
Compression fractures.
 
A: This PA view demonstrates wedging in the coronal plane. B: The more commonly recognized compression fractures involve wedging primarily in the sagittal plane with loss of anterior vertebral height.
A: This PA view demonstrates wedging in the coronal plane. B: The more commonly recognized compression fractures involve wedging primarily in the sagittal plane with loss of anterior vertebral height.
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Figure 24-3
Compression fractures.
A: This PA view demonstrates wedging in the coronal plane. B: The more commonly recognized compression fractures involve wedging primarily in the sagittal plane with loss of anterior vertebral height.
A: This PA view demonstrates wedging in the coronal plane. B: The more commonly recognized compression fractures involve wedging primarily in the sagittal plane with loss of anterior vertebral height.
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Burst fractures likely represent a more severe form of compression fracture that extends posteriorly in the vertebral body to include the posterior wall (middle column). Axial compression is the primary mechanism, although posterior ligamentous injury and/or posterior element fractures may also occur. Laminar fractures have been known to entrap the dural contents. The fractures are most common in the lower thoracic and upper lumbar levels. Associated neurologic injury is related to the severity of injury (greater injury index scores correlate with greater frequency of SCI49) and the degree of spinal canal encroachment by retropulsed bony fragments.34 SCI at the thoracolumbar junction may result in conus medullaris syndrome or cauda equina syndrome. Careful examination of the perineal area is required to identify these spinal lesions. 
Flexion–distraction injuries are especially relevant to the pediatric population because this classic lap belt injury is more frequent in backseat passengers, particularly when a shoulder strap is lacking. Motor vehicle accidents are the primary cause of this injury. The lap belt, which restrains the pelvis in adults, may ride up onto the abdomen in children. Chance, and later Smith, described how with a frontal impact, the weight of the torso is driven forward, flexing over the restraining belt. With the axis of rotation in front of the spine, distractive forces are placed on the posterior elements, with variable degrees of anterior vertebral compression. This three-column injury is generally unstable. The disruption of the posterior elements may occur entirely through the bony (Chance) or ligamentous (Smith) elements, although many times the fracture propagates through both soft and hard tissues. 
The injury is most obvious on lateral radiographs; however, if no fracture exists, widening of the intraspinous distance may be the only finding on an AP radiograph. Standard transverse plain CT imaging may also miss this injury because the plane of injury lies within the plane of imaging. One classic finding in ligamentous flexion–distraction injuries is the “empty facet” sign. When the inferior articular process of the superior vertebra is no longer in contact with the superior articular process of the inferior vertebra, the facet appears empty in the transverse CT image.26 Sagittal reconstructions are most revealing and MRI will provide information about the integrity of the PLC. Identification of a purely intravertebral flexion–distraction fracture is important, because this may alter the treatment in patients with these injuries compared to those with severe ligamentous injury. 
Fracture-dislocations of the spinal column result from complex severe loading mechanisms. These are by definition unstable injuries with a component of shearing and/or rotational displacement. A special note in the pediatric population is the documentation of this injury pattern in young patients exposed to nonaccidental trauma.18,42 
Injury patterns specific to the pediatric population that do not fit the Denis classification include apophyseal avulsion fractures and SCIWORA. Apophyseal injuries, typically of the lumbar spine, occur in adolescents as a result of trauma. The mechanism is thought to be related to flexion with a portion of the posterior corner of the vertebral body (ring apophysis) fracturing and displacing posteriorly into the spinal canal. Symptoms may mimic disc herniation, although the offending structure is bone and cartilage rather than disc material (Fig. 24-4).19,21 
Figure 24-4
Ring apophyseal avulsion injuries.
 
A: This lateral MRI image demonstrates displacement of the ring apophysis, which functionally acts as a disc herniation. This, however, represents largely a bony and cartilaginous fragment, which results in neural element compression. B: Transverse image demonstrating canal stenosis associated with this injury.
A: This lateral MRI image demonstrates displacement of the ring apophysis, which functionally acts as a disc herniation. This, however, represents largely a bony and cartilaginous fragment, which results in neural element compression. B: Transverse image demonstrating canal stenosis associated with this injury.
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Figure 24-4
Ring apophyseal avulsion injuries.
A: This lateral MRI image demonstrates displacement of the ring apophysis, which functionally acts as a disc herniation. This, however, represents largely a bony and cartilaginous fragment, which results in neural element compression. B: Transverse image demonstrating canal stenosis associated with this injury.
A: This lateral MRI image demonstrates displacement of the ring apophysis, which functionally acts as a disc herniation. This, however, represents largely a bony and cartilaginous fragment, which results in neural element compression. B: Transverse image demonstrating canal stenosis associated with this injury.
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The concept of SCIWORA was popularized by Pang and Wilberger58 who described their experience at the University of Pittsburgh. They noted a series of patients presenting with traumatic SCIs that were not evident on plain radiographs or tomograms. Several mechanisms to explain these findings have been proposed, including spinal cord stretch and vascular disruption/infarction. MRI studies have confirmed patterns of both cord edema and hemorrhage in such cases.29 Important additional facts about SCIWORA include the finding that some patients had a delayed onset of their neurologic deficits. Transient neurologic symptoms were persistent in many who later developed a lasting deficit. In addition, the younger patients (less than 8 years old) had more severe neurologic involvement.7,57,58 

Outcome Measures for Thoracolumbar Spine Fractures

SCIs in children have remarkable potential for recovery. In a study from a major metropolitan trauma center, complete SCIs were associated with fatal injuries in one-third and no neurologic recovery in another third, whereas most of the remaining one-third of patients made improvements that ultimately allowed functional ambulation. Less surprisingly, nearly all patients with incomplete SCI made some improvement over time as well.83 This ability to recover, even from complete injuries, has led some to suggest more aggressive attempts at spinal cord decompression in the early course of treatment,23,59 whereas others have suggested a period of “spinal cord rest” with observation.49 In adults, early fracture fixation has been shown to be beneficial, minimizing respiratory morbidity and decreasing days in the intensive care setting and length of hospital stay.6 There is certainly no controlled series of pediatric patients treated by both approaches to support either hypothesis. The data do, however, suggest a more optimistic view regarding the potential recovery of traumatic SCIs in children compared with adults. 
Spinal column structural integrity should be assessed in all cases of injury because the functional capacity of the vertebral elements to protect the spinal cord will continue to be required. This evaluation may be performed with functional radiographs, such as flexion–extension views (much more common in the cervical spine) or with an MRI evaluation of associated soft tissue injuries that may coexist with more obvious bony fractures. Several methods of estimating spinal column stability have been proposed including the three-column concept of Denis.17 Based on division into anterior, middle, and posterior columns, injuries to two and certainly three of these sagittal columns may be associated with an unstable injury pattern. Plain radiography with a CT scan is appropriate for evaluating the bony elements. An MRI is often required to elucidate the nature of the disc and ligamentous injuries.30,39,78 MRI is extremely sensitive and, given the brightness of edema fluid on T2 images, may be overinterpreted. A study correlating MRI and intraoperative surgical findings, however, demonstrated high levels of both sensitivity and specificity in the MRI evaluation of posterior soft tissue injuries (Fig. 24-5).46 
Figure 24-5
This sagittal MRI demonstrates marked increased signal in the posterior ligamentous complex.
 
Anteriorly a loss of height at the vertebra can be seen, suggesting a three-column spinal injury.
Anteriorly a loss of height at the vertebra can be seen, suggesting a three-column spinal injury.
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Figure 24-5
This sagittal MRI demonstrates marked increased signal in the posterior ligamentous complex.
Anteriorly a loss of height at the vertebra can be seen, suggesting a three-column spinal injury.
Anteriorly a loss of height at the vertebra can be seen, suggesting a three-column spinal injury.
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The ultimate treatment goal is a stable spinal column. This often requires surgical treatment in unstable fracture patterns. In contrast, most stable injuries can be managed nonoperatively. There are particular exceptions to these generalizations, of course. At times the associated SCI or a substantial associated deformity may alter the treatment approach to an otherwise mechanically stable injury. The presence of a complete SCI in a child younger than 10 years is also a determinant that may affect treatment strategies. The incidence of paralytic spinal deformity (scoliosis) is nearly 100% in such cases, and a long instrumented fusion will likely be required at some point.45,60 Depending on the fracture pattern and age of the patient, it may be prudent to include much of the thoracic and lumbar spine in the initial instrumented fusion.52 However, in the patient without neurologic deficit, there is evidence that the use of posterior stabilization of thoracolumbar fractures using nonfusion methods followed by removal of metal implants within an appropriate period appears to be a safe, viable option.41 

Pathoanatomy and Applied Anatomy Relating to Thoracolumbar Spine Fractures

The thoracic and lumbar spine links the upper and lower extremities through the torso. The 12 thoracic and 5 lumbar vertebrae are joined by intravertebral discs and strong ligaments, both anteriorly and posteriorly. The bony architecture of the vertebrae varies, with the smaller thoracic vertebrae having a more shingled overlapping configuration compared to the lumbar segments. The thoracic facets are oriented in the coronal plane whereas those in the lumbar spine lie nearly in the sagittal plane (Fig. 24-6). 
Figure 24-6
 
A, B: Thoracic spine posterior and lateral views demonstrating the overlapping lamina and spinous processes present in this region. The circles mark the location of the thoracic pedicles, which may be important in surgical reconstruction. C, D: Lumbar spine posterior and lateral projections demonstrating the differences in lumbar spine anatomy. Again, the circles mark locations of the lumbar pedicles relative to the facets and transverse processes.
A, B: Thoracic spine posterior and lateral views demonstrating the overlapping lamina and spinous processes present in this region. The circles mark the location of the thoracic pedicles, which may be important in surgical reconstruction. C, D: Lumbar spine posterior and lateral projections demonstrating the differences in lumbar spine anatomy. Again, the circles mark locations of the lumbar pedicles relative to the facets and transverse processes.
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Figure 24-6
A, B: Thoracic spine posterior and lateral views demonstrating the overlapping lamina and spinous processes present in this region. The circles mark the location of the thoracic pedicles, which may be important in surgical reconstruction. C, D: Lumbar spine posterior and lateral projections demonstrating the differences in lumbar spine anatomy. Again, the circles mark locations of the lumbar pedicles relative to the facets and transverse processes.
A, B: Thoracic spine posterior and lateral views demonstrating the overlapping lamina and spinous processes present in this region. The circles mark the location of the thoracic pedicles, which may be important in surgical reconstruction. C, D: Lumbar spine posterior and lateral projections demonstrating the differences in lumbar spine anatomy. Again, the circles mark locations of the lumbar pedicles relative to the facets and transverse processes.
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Mobility is less in the thoracic spine owing both to the adjacent and linked rib cage, as well as the smaller intervertebral discs. The ribs make an important connection between the vertebra with each rib head articulating across a given disc's space. This is in contrast to the relatively mobile lumbar segments, which have thick intravertebral discs that permit substantial flexion–extension, lateral bending, and axial rotation motion. The junction between the stiffer thoracic spine and more flexible lumbar spine is a region of frequent injury because of this transition between these two regions, which have differing inherent regional stability. 
Ligamentous components include the anterior and posterior longitudinal ligaments, facet capsules, ligamentum flavum, and interspinous and supraspinous ligaments. Together, these structures limit the motion between vertebrae to protect the neurologic elements. The anterior longitudinal ligament is rarely disrupted in flexion injuries but may be rendered incompetent by extension loading or a severe fracture-dislocation. On the contrary, flexion is the primary mechanism of injury to the posterior ligaments—supraspinous and interspinous, facet capsule, and ligamentum flavum. The healing capacity of the completely torn PLC is limited, whereas bony fractures are more likely to heal with resultant stability. 
The neural anatomy varies over the length of the thoracolumbar spine as well. The space within the canal is largest in the lumbar spine. The spinal cord traverses the entirety of the thoracic spine and typically terminates as the conus medullaris at the L1 or L2 level. The cauda equina occupies the dural tube below this level, and injuries below L1 are generally less likely to lead to permanent neurologic deficit. This is not to say that compression at this level cannot be serious, and careful examination of the perineum for sensation as well as rectal tone is important in the evaluation of potential conus medullaris and cauda equina syndromes. 

Thoracolumbar Spine Fracture Treatment Options: Compression Fractures

Nonoperative Treatment of Compression Fractures

Indications/Contraindications

These are nearly always stable injuries, although examination of the posterior soft tissues is required to rule out any more severe flexion–distraction injury. If there is concern for a higher energy injury a CT scan is required to rule out a burst fracture (Fig. 24-7). Indications for nonoperative treatment are intact posterior soft tissues and kyphosis less than 40 degrees. The presence of disrupted posterior soft tissues implies the injury is more significant, such as a burst fracture, which most likely will require operative intervention. 
Figure 24-7
 
A: This lateral radiograph demonstrates two upper lumbar vertebrae with slight loss of height suggestive of compression fractures. B, C: The CT images confirm an intact posterior vertebral body wall. This injury, therefore, represents a compression fracture rather than a burst fracture injury.
A: This lateral radiograph demonstrates two upper lumbar vertebrae with slight loss of height suggestive of compression fractures. B, C: The CT images confirm an intact posterior vertebral body wall. This injury, therefore, represents a compression fracture rather than a burst fracture injury.
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Figure 24-7
A: This lateral radiograph demonstrates two upper lumbar vertebrae with slight loss of height suggestive of compression fractures. B, C: The CT images confirm an intact posterior vertebral body wall. This injury, therefore, represents a compression fracture rather than a burst fracture injury.
A: This lateral radiograph demonstrates two upper lumbar vertebrae with slight loss of height suggestive of compression fractures. B, C: The CT images confirm an intact posterior vertebral body wall. This injury, therefore, represents a compression fracture rather than a burst fracture injury.
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Techniques

An isolated fracture without neurologic involvement is the most common thoracolumbar fracture pattern and can nearly always be treated with immobilization with a thoracolumbosacral orthosis (TLSO). Molding into slight hyperextension at the fracture site will limit flexion, provides pain relief, and reduces further loading of the fracture. 

Outcomes

Most fractures heal in 4 to 6 weeks without significant additional collapse; however, radiographs in the first several weeks should be obtained to follow the sagittal alignment. Long-term studies have suggested modest remodeling capacity of compression fractures occurring in childhood.38,63 Asymmetric growth at the endplates seems to allow some correction in the wedged alignment over time in the skeletally immature patient. Long-term results of compression fractures have been generally favorable, although fractures of the endplates are associated with later disc degeneration.40 
Osteoporosis of a variety of etiologies may affect children and adolescents to a degree that predisposes them to insufficiency fractures that are most often compression fractures (Fig. 24-8). Multiple-level fractures are more frequent in this setting, and problematic kyphosis may develop. Differentiating new from old fractures can be difficult if serial radiographs are not available. A TLSO for a period of time longer than typically used for simple compression fracture healing may be necessary to prevent progressive kyphosis, though treating the primary cause of the osteopenia is critical to maintaining normal alignment in such cases. An endocrinologic evaluation and assessment of bone density by dual-energy x-ray absorptiometry are advised. 
Figure 24-8
 
A: Lateral radiograph demonstrating what appears to be a routine compression fracture. The patient did not have a significant history of trauma; however, pain was present and a bone scan was obtained to further evaluate this site. B: The bone scan demonstrated markedly increased uptake, confirming an acute process and prompting additional study. C: An MRI was obtained, which demonstrated loss of height and a lesion within the anterior aspect of the vertebral body, which was later confirmed to be an infectious process.
A: Lateral radiograph demonstrating what appears to be a routine compression fracture. The patient did not have a significant history of trauma; however, pain was present and a bone scan was obtained to further evaluate this site. B: The bone scan demonstrated markedly increased uptake, confirming an acute process and prompting additional study. C: An MRI was obtained, which demonstrated loss of height and a lesion within the anterior aspect of the vertebral body, which was later confirmed to be an infectious process.
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Figure 24-8
A: Lateral radiograph demonstrating what appears to be a routine compression fracture. The patient did not have a significant history of trauma; however, pain was present and a bone scan was obtained to further evaluate this site. B: The bone scan demonstrated markedly increased uptake, confirming an acute process and prompting additional study. C: An MRI was obtained, which demonstrated loss of height and a lesion within the anterior aspect of the vertebral body, which was later confirmed to be an infectious process.
A: Lateral radiograph demonstrating what appears to be a routine compression fracture. The patient did not have a significant history of trauma; however, pain was present and a bone scan was obtained to further evaluate this site. B: The bone scan demonstrated markedly increased uptake, confirming an acute process and prompting additional study. C: An MRI was obtained, which demonstrated loss of height and a lesion within the anterior aspect of the vertebral body, which was later confirmed to be an infectious process.
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Operative Treatment of Compression Fractures

Indications/Contraindications

If the kyphosis associated with a fracture markedly alters local sagittal alignment by 30 to 40 degrees of additional relative kyphosis than would be anticipated for that region of the spine, surgical treatment may be considered. This is most frequent in multiple adjacent compression fractures that together create unacceptable focal region of relative kyphosis. 

Surgical Procedures

The preferred surgical treatment of such fractures is generally a posterior compression instrumentation construct that spans one or two levels above and below the affected vertebrae. Anterior surgical treatment is rarely required. The intact posterior vertebral wall provides a fulcrum to achieve kyphosis correction. The method of posterior fixation may be either hooks or pedicle screws. A posterior fusion over the instrumented segments ensures a lasting stable correction. Cadaver studies and clinical studies on the use of balloon vertebroplasty with calcium phosphate cement in adult patients are encouraging, as this technique may be a potentially viable option to treat compression fractures with significant angulation.43,81,82 

Thoracolumbar Spine Fracture Treatment Options: Burst Fractures

Nonoperative Treatment of Burst Fractures

Axial compression injuries that are more severe and extend into the posterior wall of the vertebral body are labeled as burst fractures. The treatment and classification of this fracture pattern are controversial areas of spinal trauma management. There are clearly some burst fractures that can be easily managed nonoperatively in a brace and others that collapse further, resulting in increased deformity unless surgically stabilized. Defining the characteristics of stable and unstable burst fractures has been attempted by several authors.17,27,53 An additional compounding variable in the treatment algorithm is SCI, which is more frequent with burst fractures than with compression fractures. 

Indications/Contraindications

Assuming an intact neurologic system, defining stable and unstable burst fractures has been attempted based on the degree of comminution, loss of vertebral height, kyphotic wedging, and integrity of the PLC. A load-sharing classification system assigns points based on comminution, fragment apposition, and kyphosis.53 Although the Denis classification suggests that all burst fractures are unstable because of the involvement of at least two columns, it is clear that in many cases the addition of a third-column injury (PLC) is required to result in a truly unstable condition. Vertebral body translation of greater than 3.5 mm has been demonstrated to predict PLC injury.64 Some advocate differentiating stable and unstable burst fractures solely on the integrity of the PLC.74,88 

Techniques

When a burst fracture is deemed stable, it must be done so on a presumptive basis. Treatment is then based on an extension molded cast or TLSO with the goal of allowing an upright position and ambulation.75 Frequent radiographic and neurologic follow-up is necessary to identify early failures. Depending on the age of the patient and severity of the fracture, immobilization is suggested for a duration of 2 to 4 months. 

Outcomes

Studies of immature patients treated for burst fractures are uncommon,44 yet much of the adult literature provides valuable information about the outcomes to expect following nonoperative treatment. Most of these fractures in adults heal with little change in kyphosis and function and minimal, if any, residual pain.28,85 It is reasonable to expect adolescent patients to heal at least as well and probably even faster. Wood et al.88 compared operative and nonoperative treatment in a prospective randomized study of patients with burst fractures who were neurologically intact with a normal PLC. The radiologic and functional outcomes were not substantially different, and these authors concluded that nonoperative treatment should be considered when the PLC and neurologic function are intact.88 Functional outcome does not appear to correlate with the degree of spinal kyphosis, although long-term studies of scoliosis treatment do suggest that an alteration of sagittal alignment may be detrimental (flat back syndrome) in the long term. 

Operative Treatment of Burst Fractures

Indications/Contraindications

Fractures with three-column involvement, neurologic deficit, concomitant musculoskeletal injury, and thoracic/abdominal injury precluding the use of a brace have all been reported as indications for surgical management of burst fractures. Contraindications mainly center on medical conditions (coexisting or new) which make surgical intervention too risky. 

Surgical Procedure

Even some fractures with PLC disruption have been successfully treated nonoperatively15; however, these three-column injuries are often operatively stabilized. When surgical treatment is selected, either an anterior or posterior approach can be used, although this also remains controversial. Anterior stabilization generally involves discectomy and strut grafting that spans the fractured vertebra. Stabilization with a plate or dual-rod system is appropriate. Posterior options include pedicle screw fixation one or two levels above and below the fractured vertebra. Advances in the application of posterior instrumentation for thoracolumbar fractures have demonstrated encouraging, early outcomes with fracture stabilization without fusion and in minimally invasive surgical techniques.84,86 
The decision to proceed anteriorly or posteriorly for the surgical treatment of a burst fracture is largely dictated by surgeon preference and, to some degree, the features of the fracture. Posterior approaches are familiar to all surgeons and can easily be extended over many levels. In addition, a transforaminal lumbar interbody fusion (TLIF) can be performed if anterior interbody support is deemed beneficial to construct stability. Decompression of the spinal cord can be achieved by indirect or direct methods. Restoration of the sagittal alignment frequently leads to spontaneous repositioning of the posteriorly displaced vertebral body fracture fragments. If additional reduction of posterior wall fragments is required, direct fracture reduction can be accomplished with a posterolateral or transpedicular decompression.23 This also allows additional anterior column bone grafting that may add structural integrity and speed fracture healing. 
The anterior approach allows direct canal decompression through a corpectomy of the fractured vertebra. Structural strut grafting restores the integrity of the anterior column. With this graft, a load-sharing anterior plate or rod system completes the reconstruction. This approach deals most directly with the pathology, which in burst fractures lies within the anterior and middle vertebral columns (Fig. 24-9). Proponents of the anterior approach cite better biomechanical stabilization of the unstable spine, better correction of segmental kyphosis, and less loss of correction postoperatively.72,73,89 In adults, a combined anterior and posterior approach may provide the best stability and sagittal alignment, especially in very unstable injuries. However, the increased morbidity with this approach is likely not necessary routinely in the pediatric/adolescent patient population.66 
Figure 24-9
Burst fracture.
 
A: This teenage patient presented with loss of vertebral body height associated with a motorcycle accident after jumping more than 20 ft. His neurologic examination was intact. B: CT scan confirmed a burst fracture component with very little retropulsion into the spinal canal. This appeared to be a stable injury and was initially managed with an orthosis. There was poor compliance with the orthosis and further collapse (C, D). Given the lack of compliance and progressive kyphosis, the patient underwent anterior reconstruction with an iliac crest strut graft and plating (E, F).
A: This teenage patient presented with loss of vertebral body height associated with a motorcycle accident after jumping more than 20 ft. His neurologic examination was intact. B: CT scan confirmed a burst fracture component with very little retropulsion into the spinal canal. This appeared to be a stable injury and was initially managed with an orthosis. There was poor compliance with the orthosis and further collapse (C, D). Given the lack of compliance and progressive kyphosis, the patient underwent anterior reconstruction with an iliac crest strut graft and plating (E, F).
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A: This teenage patient presented with loss of vertebral body height associated with a motorcycle accident after jumping more than 20 ft. His neurologic examination was intact. B: CT scan confirmed a burst fracture component with very little retropulsion into the spinal canal. This appeared to be a stable injury and was initially managed with an orthosis. There was poor compliance with the orthosis and further collapse (C, D). Given the lack of compliance and progressive kyphosis, the patient underwent anterior reconstruction with an iliac crest strut graft and plating (E, F).
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Figure 24-9
Burst fracture.
A: This teenage patient presented with loss of vertebral body height associated with a motorcycle accident after jumping more than 20 ft. His neurologic examination was intact. B: CT scan confirmed a burst fracture component with very little retropulsion into the spinal canal. This appeared to be a stable injury and was initially managed with an orthosis. There was poor compliance with the orthosis and further collapse (C, D). Given the lack of compliance and progressive kyphosis, the patient underwent anterior reconstruction with an iliac crest strut graft and plating (E, F).
A: This teenage patient presented with loss of vertebral body height associated with a motorcycle accident after jumping more than 20 ft. His neurologic examination was intact. B: CT scan confirmed a burst fracture component with very little retropulsion into the spinal canal. This appeared to be a stable injury and was initially managed with an orthosis. There was poor compliance with the orthosis and further collapse (C, D). Given the lack of compliance and progressive kyphosis, the patient underwent anterior reconstruction with an iliac crest strut graft and plating (E, F).
View Original | Slide (.ppt)
A: This teenage patient presented with loss of vertebral body height associated with a motorcycle accident after jumping more than 20 ft. His neurologic examination was intact. B: CT scan confirmed a burst fracture component with very little retropulsion into the spinal canal. This appeared to be a stable injury and was initially managed with an orthosis. There was poor compliance with the orthosis and further collapse (C, D). Given the lack of compliance and progressive kyphosis, the patient underwent anterior reconstruction with an iliac crest strut graft and plating (E, F).
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Thoracolumbar Spine Fracture Treatment Options: Flexion–Distraction Injuries (Chance Fractures)

Nonoperative Treatment of Chance Fractures

Indications/Contraindications

The treatment of flexion–distraction injuries is dictated by the particular injury pattern and the associated abdominal injuries. In general, these fractures are reduced by an extension moment that can be maintained with either a cast or internal fixation. A hyperextension cast is ideal for younger patients (less than approximately 10 years) with a primary bony injury pattern and no significant intra-abdominal injuries. As described above, the posterior disruption may pass through ligaments or joint capsules in a purely soft tissue plane of injury or traverse an entirely bony path. The distinction is important, because bony fractures have the potential for primary bony union, whereas the severe ligamentous injuries are less likely to heal with lasting stability without surgical intervention. 

Technique

Hyperextension cast or TLSO as detailed for compression and burst fractures. 

Outcomes

Nonoperative treatment has been demonstrated to be effective in selected patients. The most frequent problem with the nonoperative approach has been progression of the kyphotic deformity.2 

Operative Treatment of Chance Fractures

Indications/Contraindications

The greater the degree of ligamentous/facet disruption, the more likely the need for stabilization with an arthrodesis of the injured motion segment. In addition, the greater the degree of injury kyphosis the more likely posttraumatic kyphosis will become a problem.2 

Surgical Procedure

Options for internal fixation include posterior wiring in young children (supplemented with a cast) and segmental fixation in a primarily compressive mode (Fig. 24-10). This approach can decrease the injury kyphosis and maintain this alignment during the healing process. Operative treatment has been demonstrated to have a good clinical outcome in 84% of pediatric patients, compared to 45% in the nonoperative group (NS).2 
Figure 24-10
Flexion–distraction injury.
 
A, B: Plain radiographs of a restrained backseat passenger who was involved in a motor vehicle accident. The wedging of L2 with posterior distraction is visible on the lateral radiograph. The intraspinous widening is noted on the AP radiograph as well (arrows). C: Sagittal CT images confirm the injury pattern. D: Lateral radiographs following reconstruction with posterior spinal instrumentation.
A, B: Plain radiographs of a restrained backseat passenger who was involved in a motor vehicle accident. The wedging of L2 with posterior distraction is visible on the lateral radiograph. The intraspinous widening is noted on the AP radiograph as well (arrows). C: Sagittal CT images confirm the injury pattern. D: Lateral radiographs following reconstruction with posterior spinal instrumentation.
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A, B: Plain radiographs of a restrained backseat passenger who was involved in a motor vehicle accident. The wedging of L2 with posterior distraction is visible on the lateral radiograph. The intraspinous widening is noted on the AP radiograph as well (arrows). C: Sagittal CT images confirm the injury pattern. D: Lateral radiographs following reconstruction with posterior spinal instrumentation.
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Figure 24-10
Flexion–distraction injury.
A, B: Plain radiographs of a restrained backseat passenger who was involved in a motor vehicle accident. The wedging of L2 with posterior distraction is visible on the lateral radiograph. The intraspinous widening is noted on the AP radiograph as well (arrows). C: Sagittal CT images confirm the injury pattern. D: Lateral radiographs following reconstruction with posterior spinal instrumentation.
A, B: Plain radiographs of a restrained backseat passenger who was involved in a motor vehicle accident. The wedging of L2 with posterior distraction is visible on the lateral radiograph. The intraspinous widening is noted on the AP radiograph as well (arrows). C: Sagittal CT images confirm the injury pattern. D: Lateral radiographs following reconstruction with posterior spinal instrumentation.
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A, B: Plain radiographs of a restrained backseat passenger who was involved in a motor vehicle accident. The wedging of L2 with posterior distraction is visible on the lateral radiograph. The intraspinous widening is noted on the AP radiograph as well (arrows). C: Sagittal CT images confirm the injury pattern. D: Lateral radiographs following reconstruction with posterior spinal instrumentation.
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Thoracolumbar Spine Fracture Treatment Options: Fracture-Dislocations

Operative Treatment of Fracture-dislocations

Indications/Contraindications

These highly unstable injuries nearly always require surgical stabilization. When the spinal cord function remains intact, instrumented fusion gives the greatest chance for maintaining cord function. On the other hand, if a complete SCI has occurred, internal fixation will aid in the rehabilitation process, allowing early transfers and upright sitting. 

Surgical Procedure

The typical procedure is a posterior instrumented fusion which extends at least two levels above and below the level of injury to ensure restoration of alignment and stability. In cases of SCI below the age of 10 years, a longer fusion may be considered to reduce the incidence and severity of subsequent paralytic scoliosis. Those injured after the adolescent growth spurt are at low risk for late deformity if the fracture is well aligned at the time of initial fixation (Fig. 24-11). 
Figure 24-11
 
A, B: AP and lateral radiographs demonstrating reconstruction after a lower thoracic level complete SCI associated with fracture-dislocation in the lumbar spine combined with a burst fracture in the lower thoracic spine. Given the complete paraplegia present, a relatively long instrumentation construct was selected to provide a stable foundation in this skeletally immature patient. Four years postoperatively, the patient has no evidence of progressive spinal deformity; however, there is certainly some risk remaining of developing pelvic obliquity and upper thoracic deformity given the paraplegia.
A, B: AP and lateral radiographs demonstrating reconstruction after a lower thoracic level complete SCI associated with fracture-dislocation in the lumbar spine combined with a burst fracture in the lower thoracic spine. Given the complete paraplegia present, a relatively long instrumentation construct was selected to provide a stable foundation in this skeletally immature patient. Four years postoperatively, the patient has no evidence of progressive spinal deformity; however, there is certainly some risk remaining of developing pelvic obliquity and upper thoracic deformity given the paraplegia.
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Figure 24-11
A, B: AP and lateral radiographs demonstrating reconstruction after a lower thoracic level complete SCI associated with fracture-dislocation in the lumbar spine combined with a burst fracture in the lower thoracic spine. Given the complete paraplegia present, a relatively long instrumentation construct was selected to provide a stable foundation in this skeletally immature patient. Four years postoperatively, the patient has no evidence of progressive spinal deformity; however, there is certainly some risk remaining of developing pelvic obliquity and upper thoracic deformity given the paraplegia.
A, B: AP and lateral radiographs demonstrating reconstruction after a lower thoracic level complete SCI associated with fracture-dislocation in the lumbar spine combined with a burst fracture in the lower thoracic spine. Given the complete paraplegia present, a relatively long instrumentation construct was selected to provide a stable foundation in this skeletally immature patient. Four years postoperatively, the patient has no evidence of progressive spinal deformity; however, there is certainly some risk remaining of developing pelvic obliquity and upper thoracic deformity given the paraplegia.
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Author's Preferred Treatment for Thoracolumbar Spine Fractures

Compression Fractures

Nearly all are managed nonoperatively in an off-the-shelf TLSO brace. Occasionally, a fracture is too proximal for such an orthosis and an extension to the chin/occiput is required. For fractures proximal to T6, a Minerva brace is used. These fractures typically heal within 4 to 6 weeks, when the immobilization can be discontinued. Activities should be limited for an additional 6 weeks. Compression fractures with more than 50% loss of anterior vertebral height are considered for either a closed reduction in an extension molded body cast or surgical correction with posterior instrumentation. The determination of which of these two approaches to choose is based on associated injuries and a discussion with the family. Compression fractures associated with neurologic injury are managed surgically. 

Burst Fractures

Our preferred approach to neurologically intact patients with burst fractures is nonoperative approach in light of recent studies. If the neurologic status is normal and the posterior soft tissues are intact, a TLSO or cast is used for 3 months. A cast is used when local kyphosis is more than 20 degrees, and the cast is placed in a hyperextension position in an attempt to restore sagittal alignment. If the posterior soft tissues are disrupted (and the patient is neurologically intact), posterior surgical stabilization is preferred. An anterior decompression can be performed for canal compromise, especially when greater than 50% of spinal canal volume. 

Flexion–distraction Injuries

Our treatment of Chance fractures is based on two findings: Associated abdominal injuries and the presence of a ligamentous component to the fracture. If either exists, surgical treatment is the preferred approach. Casting in extension is appropriate for fractures that transverse an entirely bony plane without intra-abdominal pathology. A thigh is incorporated into the cast for greater control of lumbar lordosis. Surgical treatment is by a posterior approach and includes only the involved vertebrae. Monosegmental pedicle screw fixation is generally preferred. 

Fracture-dislocation

Posterior surgery is the treatment of choice for all fracture-dislocations with or without neurologic injury (Fig. 24-12). The timing of such intervention depends on the associated injuries and the ability of the patient to tolerate surgical intervention; however, stabilization as early as possible is preferred. SCI nearly always complicates the management of these injuries, and a deteriorating neurologic examination makes surgical treatment of the spine an emergency that should be treated as quickly as possible. 
Figure 24-12
 
A, B: This 8-month-old child presented with an incomplete SCI and a thoracolumbar fracture-dislocation due to nonaccidental trauma. The malalignment of the vertebral segments is noted on both the AP and lateral projections. C: The MRI demonstrated a three-column injury with a fracture through the vertebral endplate. D, E: The patient had an open reduction and instrumentation with pedicle screw fixation using a 3.5-mm cervical system.
A, B: This 8-month-old child presented with an incomplete SCI and a thoracolumbar fracture-dislocation due to nonaccidental trauma. The malalignment of the vertebral segments is noted on both the AP and lateral projections. C: The MRI demonstrated a three-column injury with a fracture through the vertebral endplate. D, E: The patient had an open reduction and instrumentation with pedicle screw fixation using a 3.5-mm cervical system.
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A, B: This 8-month-old child presented with an incomplete SCI and a thoracolumbar fracture-dislocation due to nonaccidental trauma. The malalignment of the vertebral segments is noted on both the AP and lateral projections. C: The MRI demonstrated a three-column injury with a fracture through the vertebral endplate. D, E: The patient had an open reduction and instrumentation with pedicle screw fixation using a 3.5-mm cervical system.
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Figure 24-12
A, B: This 8-month-old child presented with an incomplete SCI and a thoracolumbar fracture-dislocation due to nonaccidental trauma. The malalignment of the vertebral segments is noted on both the AP and lateral projections. C: The MRI demonstrated a three-column injury with a fracture through the vertebral endplate. D, E: The patient had an open reduction and instrumentation with pedicle screw fixation using a 3.5-mm cervical system.
A, B: This 8-month-old child presented with an incomplete SCI and a thoracolumbar fracture-dislocation due to nonaccidental trauma. The malalignment of the vertebral segments is noted on both the AP and lateral projections. C: The MRI demonstrated a three-column injury with a fracture through the vertebral endplate. D, E: The patient had an open reduction and instrumentation with pedicle screw fixation using a 3.5-mm cervical system.
View Original | Slide (.ppt)
A, B: This 8-month-old child presented with an incomplete SCI and a thoracolumbar fracture-dislocation due to nonaccidental trauma. The malalignment of the vertebral segments is noted on both the AP and lateral projections. C: The MRI demonstrated a three-column injury with a fracture through the vertebral endplate. D, E: The patient had an open reduction and instrumentation with pedicle screw fixation using a 3.5-mm cervical system.
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Steroid Treatment

Despite the controversies, we continue to follow the recommendations of the Third National Acute Spinal Cord Injury Study and prescribe methylprednisolone if it can be given within 8 hours of the time of injury. We are skeptical that this provides significant benefit, but we believe this remains the current medical and legal standard. 

Potential Pitfalls and Preventative Measures in Thoracolumbar Spine Fractures

Pitfalls

  •  
    Watch for associated injuries, both musculoskeletal and others.
  •  
    Do not let MRI/CT findings replace a careful examination of the back.
  •  
    Monitor neurologic status carefully because an unrecognized change may limit the ability to intervene early and prevent permanent sequelae.

Preventative Measures

  •  
    Do not hesitate to get advanced imaging, especially CT imaging.
  •  
    Understand the mechanics of the injury to develop a rational treatment plan.
  •  
    Always seek to identify additional levels of spinal injury when one is discovered.
  •  
    Document the neurologic examination precisely and repeat it often.

Summary, Controversies, and Future Directions Related to Thoracolumbar Spine Fractures

Several areas of controversy remain with regards to the management of acute SCI associated with thoracolumbar fractures. These include both nonoperative and operative methods of treatment. Investigations into the benefits of steroids in mitigating the effects of the secondary phase of SCI that follows the acute trauma have been mixed, although clinical trials have suggested benefit in specific instances. 
SCI that results from direct trauma may acutely disrupt the neural tissue, possibly with compression remaining from fracture fragments or displacement. Once the initial injury occurs, biochemical cascades are set into motion, resulting in further injury of spinal cord tissue. Experimental studies have suggested that steroids administered early in the post injury period could limit these detrimental secondary effects. Based on randomized clinical trials of methylprednisolone administration after acute SCI,8,9 current recommendations for steroid use are dependent on the timing of administration relative to the occurrence of the injury. If the time lapse is less than 3 hours, a bolus of 30 mg/kg of methylprednisolone is followed by an hourly infusion of 5.4 mg/kg for 24 hours duration. If the lapse between injury and treatment is 3 to 8 hours, an infusion of the same dose is continued for 48 hours. More importantly, if more than 8 hours have passed following the SCI, no steroids are recommended.9 
The benefit of steroids with regard to functional levels of recovery has been questioned, and in all studies of high-dose steroid use, there has been an increased complication rate. Infection is the most common with both pneumonia and sepsis occurring. Steroids are known to depress the immune response.22 These issues have resulted in an inconsistent adoption of the National Acute Spinal Cord Injury Study recommendations. 
The timing and necessity of spinal decompression for an SCI also remains debated. Traditional teaching suggests no benefit to decompression when a complete SCI exists. This may be true, but if early decompression of an incomplete SCI is beneficial, and there are experimental data to suggest it is, then it may be impossible to determine early on if the patient has an incomplete injury but remains in spinal shock. Spinal shock may last for 24 hours, leaving an incomplete SCI patient completely unresponsive with regard to spinal cord function. The data to suggest a benefit to early decompression are largely experimental; however, a clinical study also reported a benefit. In a series of 91 pediatric patients, 66 with immediate decompression were compared to 25 with whom decompression was delayed. Improvement of at least one Frankel grade occurred in one-half of the early decompression patients compared to one-quarter of those who had delayed decompression.59 Early surgery has been documented to shorten the intensive care unit stays and length of hospitalizations, shorten time on mechanical ventilation support, and lower overall complication rates in patients with thoracolumbar spine injuries.14 
In pediatric patients with SCI, it is difficult to argue against spinal cord decompression if the MRI documents persistent compression in the setting of an SCI. Pediatric patients have a substantial potential for recovery, and reducing pressure on the neural elements may be important in maximizing functional recovery. There is little controversy if spinal cord function is deteriorating in a patient with a known compressive lesion. This is an emergency that warrants decompression by either an anterior or posterior approach. Realignment of the spinal column and removal of fragments from the canal are required. The exact surgical approach depends on the location of offending structures and the nature of the instability. 

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