Thoracic and Lumbar Spine Injuries



Thoracic and Lumbar Spine Injuries


Andrew Jea MD

James M. Drake BSE, MBBCh, iMSc, FRCSC, FACS



EPIDEMIOLOGY



  • Spinal cord injury (SCI) in children is uncommon.



    • Children account for only 0.65% to 9.47% of all SCI.1, 2, 3 and 4


    • The incidence of spinal cord injury without radiographic abnormality (SCIWORA) is 15% to 66% of all SCI.3, 4, 5, 6 and 7


  • Spine fractures in children represent 1% to 2% of all pediatric fractures.8



    • The thoracic region (T2-T10) is most commonly injured followed by the lumbar region (L2-L5).9


  • Trauma to the lower thoracic or lumbar spine in children is rarely associated with spinal cord injury.8


  • Each year 1,000 new spinal cord injuries are reported in children.10



    • Adolescent boys are most affected.11


    • Causes of pediatric spine injury include falls, athletic activities, child abuse, and motor vehicle trauma.11, 12, 13, 14, 15 and 16


ANATOMY



  • Embryology of the thoracic and lumbar vertebrae.



    • Three main ossification centers:8



      • One each for the left and right sides of the neural arch.


      • One for the body.


    • Junction of the arches with the body occurs at the neurocentral synchondrosis.



      • Remains visible radiographically until 3 to 6 years old.


      • Lies just anterior to the pedicle base.


      • Often mistaken for a congenital anomaly or fracture in younger children.8


    • Secondary centers of ossification occur in flattened, disc-shaped epiphyses superior and inferior to each vertebral body.



      • Provides longitudinal growth.17


      • Ossification of these growth plates at age 7 to 8 years creates the radiographic impression of a groove at the corner of each vertebral body.


      • Ligaments and discs attach to this groove, which is an apophyseal ring.


      • The ring develops its own ossification center by the age of 12 to 15 and fuses with the remainder of the vertebra at skeletal maturity.18


  • Differences in the pediatric spinal column compared to adults predispose infants and small children to flexion and extension injuries.



    • Pediatric spine has ligamentous laxity, elasticity, and incomplete ossification.3,19


    • Small children have proportionally larger heads with underdeveloped neck musculature.3,8


    • Small children’s facet joints are more horizontally oriented.



      • Results in greater mobility and less stability.3,20,21



    • Physiologic wedging of the vertebral bodies.



      • Particularly of the upper cervical spine.


      • Facilitates forward movement of the vertebra.


      • Predisposes children to flexion injuries.3,20,21


    • Hyperextension coupled with the hypermobility:



      • Results in momentary dislocation then spontaneous reduction.


      • Results in spinal cord damage with a normal-appearing vertebral column.3,22


EVALUATION


History



  • Back pain from a major accident or fall increases suspicion for spine injury.



    • Major accident includes significant vehicular damage, head-on, high-speed collision, rollover, or death at the scene.


  • Accidents involving the lack of seatbelts, prolonged extrication, airbag deployment, steering wheel or windshield damage, passenger ejection, or space intrusion can be associated with spine injuries.


  • Vehicle accidents involving motorcycles, bicycles, or pedestrians have a high association with spine injuries.


  • Transient or persistent symptoms include pain, weakness, numbness, and tingling.


Physical Exam



  • A seatbelt mark across the abdomen, or intra-abdominal injury, should increase suspicion for possible thoracic or lumbar fracture.8


  • Look for tenderness, swelling, ecchymosis, or a palpable defect posteriorly along the spinous processes.8


  • Lower thoracic and upper lumbar injuries (T11-L1) are associated with increased risk of gastrointestinal injury.


  • Lumbar and sacral injuries (L2-sacral) are associated with risks of orthopedic and gastrointestinal injuries.11


  • Accurately document any loss of sensation or motor function.8


  • Spinal cord injury above the T6 level can present with spinal or neurogenic shock (bradycardia and hypotension).23



    • Represents a loss of descending sympathetic tone.


    • Spinal shock must be recognized early.


    • Pure fluid and blood resuscitation may not be effective.


    • A vasopressor may be needed to restore adequate perfusion.


INITIAL MANAGEMENT


Spine Stabilization



  • The mainstay of spinal injury management is to immobilize the affected levels.



    • In the field, this means immobilizing the entire spinal axis.23


  • Use an appropriately sized cervical collar!



    • If proper collar is unavailable, blocks and tape are effective for immobilizing the head on the backboard.23


  • Children’s disproportionate large head places them in flexion when positioned on a neutral board.



    • Proper immobilization requires either:



      • A special board with a recess for the occiput, allowing the head to rest in line with the body.


      • Placement of a thin cushion under the torso relative to the head.23


  • See Chapter 9 on C-spine Injuries for details.


SPINAL IMAGING


Plain Radiographs



  • AP and lateral radiographs can detect most osseous injuries in children and give an excellent global view of the spine.23



  • Flexion/extension x-rays are important to rule out subluxation in any patient with reported transient neurologic symptoms.20


  • Paraspinous muscles will often “splint” the spine, rendering any subluxation undetectable in the acute setting.


  • Obtain follow-up x-rays 5 to 7 days after muscle spasm subsides.20


Computed Tomography



  • If plain films are negative but clinical suspicion remains high, high-quality CT scans may be obtained to identify an occult, and possibly surgically correctable, vertebral fracture or dislocation.20


  • CT seems less helpful in pediatric spine’s routine evaluation because children are more likely than adults to have ligamentous injury without fracture.


Magnetic Resonance Imaging



  • The modality of choice in the pediatric patient with apparent spinal cord injury but negative radiographic studies.


  • Sensitive at detecting ligamentous disruptions and instability not seen on plain radiographs.24


  • Demonstrates extent of actual spinal cord damage, ranging from mild hemorrhage and/or edema to cord transection.25


  • Findings are prognostic of patient outcome.25


  • A normal-appearing MRI suggests excellent recovery.


  • Findings of major hemorrhage or cord transection are associated with permanent cord injury.


  • Can also rule out surgical lesions (those causing persistent cord compression, such as epidural hematoma or traumatic disc herniation).26, 27 and 28


MANAGEMENT



  • Assess in hospital using a systematic approach to spine fractures (Fig. 13-1).


  • Issue of immediate stability (e.g., whether or not there is a need for rigid immobilization at the time of presentation) based on the specific fracture type (Table 13-1).29



    • Definition of stability based on the injured spinal column’s remaining ability to bear normal physiologic loads without further neurologic compromise.29


    • Majority of thoracic and lumbar spine fractures in children and younger adolescents are minor, stable, and without neurologic deficit.8


    • Bed rest and gradual resumption of activities are generally sufficient for managing these injuries.8


  • Determining need for neurologic decompression (Fig. 13-1).29



    • In most instances, emergent decompression is unnecessary for the patient with a complete thoracic spinal cord injury associated with a spinal fracture.29,30


    • Spinal cord injury in this setting involves “supra-threshold” forces causing irreversible damage regardless of treatment.29,30


  • Thoracic spinal cord made up primarily of delicate white matter tracts.


  • T4-T8 levels represent the spinal cord’s primary vascular watershed zone.


  • Emergent decompression justified for:

Jun 22, 2016 | Posted by in EMERGENCY MEDICINE | Comments Off on Thoracic and Lumbar Spine Injuries

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