Rosen & Barkin's 5-Minute Emergency Medicine Consult (668 page)

• The following forces account for most thoracic fractures and dislocations:
  
  • Axial compression
    
  • Flexion–rotation
    
  • Shear
    
  • Flexion–distraction
    
  • Extension
    
• 3 anatomically distinct columns; if 2 of the 3 columns are disrupted, the spinal column is unstable:
  
  • Posterior column: Posterior bony arch and interconnecting ligamentous structures
    
  • Middle column: Posterior aspects of the vertebral bodies, posterior annulus fibrosis, and posterior longitudinal ligament
    
  • Anterior column: Anterior longitudinal ligament, anterior annulus fibrosis, and anterior vertebral body
    
• Major vs. minor fractures:
  
  • Minor:
    
    • Isolated articular fracture
      
    • Transverse process fracture
      
    • Spinous process fracture
      
    • Pars interarticularis fracture
      
  • Major:
    
    • Compression fracture
      
    • Burst fracture
      
    • Seat belt injury
      
    • Fracture–dislocation
      
• Compression fracture (anterior or lateral flexion):
  
  • Fracture of anterior portion of vertebral body with intact middle column
    
  • May be posterior column disruption
    
  • Type A: Fracture through both end plates
    
  • Type B: Fracture through superior end plate
    
  • Type C: Fracture through inferior end plate
    
  • Type D: Both end plates intact
    
• Burst fracture (axial loading):
  
  • Fracture through middle column of spine
    
  • May have spreading of posterior elements and laminar fractures with possible retropulsion into the spinal canal and potential neurologic compromise
    
  • Type A: Fracture through both end plates
    
  • Type B: Fracture through superior end plate
    
  • Type C: Fracture through inferior end plate
    
  • Type D: Burst in middle column with rotational injury leading to subluxation
    
  • Type E: Burst in middle column with asymmetric compression of anterior column
    
• Seat belt injury (flexion–distraction):
  
  • Distraction of posterior and middle columns with anterior column intact
    
  • Typically caused by lap belts used without shoulder harness
    
  • Type A: Through bone
    
  • Type B: Primarily ligamentous
    
  • Type C: Disruption of bone through middle column
    
  • Type D: Through ligaments and disc with no middle column fracture
    
• Fracture dislocations:
  
  • Failure of all 3 columns following compression, tension, rotation, or shear forces
    
  • Type A: Flexion–rotation; fall from height
    
  • Type B: Shear-violent force across long axis of trunk
    
  • Type C: Flexion–distraction; bilateral facet dislocation
    

• Thoracic spine is rigid owing to the support of the rib cage and the costovertebral articulations:
  
  • The spinal canal is narrowest in the thoracic spine
    
• Traumatic thoracic spine fractures require enormous forces. Motor vehicle and motorcycle collisions, pedestrian’s struck, and falls (particularly from height >10 ft) account for most fractures:
  
  • A small percentage are caused by penetrating injuries (see “Spinal Cord Syndromes”)
    
  • 50% of all spinal fractures and 40% of all spinal cord injuries occur at the thoracolumbar junction (T11–L2)
    

• Suspect child abuse if thoracic spine injury without clear history of motor vehicle trauma.
  
• Posterior rib fractures raise index of suspicion for abuse and require closer survey of thoracic spine and entire body for occult injury.
  

Increased brittleness of bones in elderly (>65 yr) predispose to fractures with less severe mechanism, falls from lesser height.

DIAGNOSIS

• Significant force is required to produce thoracic vertebral fractures.
  
• Pain at the fracture site or impingement of nearby structures by bone fragments.
  
• Because of the stabilizing influence of the rib cage, a tremendous amount of force is needed to cause thoracic spine dislocations:
  
  • Concomitant internal injury should be suspected
    
  • Thoracic spine fracture–dislocation is less common than thoracolumbar fracture–dislocation but has higher incidence of neurologic impairment
    
  • Spinal injury at another anatomic level should heighten suspicion for thoracic injury and vice versa
    
• Common signs and symptoms:
  
  • Localized soft tissue defect
    
  • Ecchymosis or hematoma:
    
    • Scapular contusions
      
  • Step-offs, deformity, or widening of disc space (more specific)
    
  • Pain or tenderness (more sensitive):
    
    • Localized—pain and tenderness over spinous process
      
    • Referred—paraspinal, anterior chest, or abdomen
      
  • Paraspinal muscle spasm
    
  • Paresthesia or dysesthesia
    
  • Weakness (focal or global)
    
  • Distal areflexia, flaccid plegia
    
  • Bowel or bladder incontinence
    
  • Priapism
    
  • Loss of temperature control
    
  • Spinal shock—hypotension with bradycardia
    

• Mechanism of injury
  
• Comorbidities
  

• Rapid evaluation of ABCs.
  
• Primary and secondary trauma survey.
  
• Detailed neurologic exam, including rectal tone and perianal sensation.
  
• Thorough spine exam for deformity or tenderness.
  
• Any midline tenderness elicited on exam, distracting injury, altered mental status or intoxication with concerning mechanism mandates plain film spine radiography.
  
• If fracture present, determine whether it is stable or unstable.
  
• Assess for bulbocavernosus reflex in spinal shock.
  

• Midline pain or tenderness, significant motor vehicle accident, or falls from height are indications for screening with anteroposterior and lateral plain film views of the spine.
  
• Thin-cut CT scanning is indicated in any patient with evidence of spinal fracture on plain films and patients with normal plain films and significant pain or tenderness and mechanism for severe injury. Patients with mediastinal widening on plain film should also have evaluation for thoracic spine injury or aortic injury.
  
• Any finding of a fracture anywhere in the thoracic spine mandate imaging of the entire spine with plain radiographs at a minimum as 10% patients will have an additional fracture.
  
• Data from the CT of the chest/abdomen/pelvis are increasingly being reformatted to clear the thoracolumbar spine in trauma patients:
  
  • More sensitive than plain radiographs without additional cost or radiation
    
• MRI for further evaluation of suspected spinal cord injury, compression, or ligamentous tear.
  

• Arthritis (degenerative and rheumatoid)
  
• Ankylosing spondylitis
  
• Spina bifida
  
• Congenital malformation
  
• Degenerative disc disease
  
• Neoplasm
  
• Pathologic fracture:
  
  • Osteoporosis
    
  • Benign or malignant bone tumors
    

TREATMENT

• If the patient’s positioning initially prevents placement of a long spinal board, a short board should be placed until the patient is fully extricated.
  
• Patients with neurologic deficit should be transported directly to a trauma center.
  

• Manage airway and resuscitate as indicated:
  
  • Airway intervention should be done with inline cervical immobilization
    
  • Identify hypotension that may be secondary to hemorrhage vs. neurogenic
    
  • Patients with hypotension in setting of trauma should be treated as hypovolemic from hemorrhage until proven otherwise
    
  • Consider fluid resuscitation with crystalloid followed by blood products if indicated
    
• Preserve residual spinal cord function and prevent further injury by stabilizing the spine.
  

• Perform all needed resuscitation and diagnostic tests with the patient in full spinal immobilization. This does not require the use of the spinal board which should be removed promptly on arrival during the initial exam.
  
• If spinal cord injury is suspected, consider the administration of high-dose steroids and consult a spine surgeon.
  
• If spinal fracture or ligamentous injury is suspected without neurologic impairment, arrange CT or MRI scanning while consulting neurosurgery or orthopedic surgery.
  
• Pain control should be administered as soon as possible; NSAIDs, opiates, and benzodiazepines are the mainstays of treatment.
  
• Neurogenic hypotension presents with bradycardia or normal heart rate and patient will be warm from peripheral vasodilation. This is in contrast to the tachycardia and cool extremities seen with hypovolemic shock:
  
  • Neurogenic hypotension should be treated with crystalloid bolus but may require vasopressors
    

• High-dose steroid administration is rapidly falling out of favor due to lack of evidence supporting use and risk of untoward effects of steroids.
  
• If given, must be within 8 hr of injury as indicated by regional/hospital protocol.
  
• Methylprednisolone: 30 mg/kg IV bolus over 15 min followed 45 min later by a maintenance infusion of 5.4 mg/kg/h for the next 23 hr if started within 3 hr of injury; consider continuing for 48 hr if started 3–8 hr after injury.
  
• High-dose steroid treatment not recommended >8 hr after injury.
  

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