Spine Injury: Lumbar

Description

• Flexion compression fracture:
  • Wedge compression:
    • If <50% anterior compression of the vertebral body, injury considered stable
    • No ligamentous injury
    • No neurologic deficit
  • Burst fracture:
    • Vertebral body fracture with retropulsion of bone into the neural canal
    • Kyphosis evident on lateral radiograph
    • Posterior ligamentous injury
    • Anterior compression, lower extremities, calcaneal fractures
    • Possible neurologic deficit
• Flexion distraction (lap belt injury):
  • Abdominal injuries commonly associated
  • Chance fracture:
    • Pure bony injury; fracture line through spinous process, pedicles, and vertebral body
    • No kyphosis evident on lateral radiograph
    • Often no neurologic deficit
  • Facet dislocation:
    • Mostly soft tissue injury; no fracture
    • Complete disruption of posterior ligaments and intervertebral disc
    • Neurologic deficit may be present
• Flexion rotation:
  • Unstable injury
  • Neurologic deficit often present
• Extension:
  • Unstable, uncommon
  • Disruption of anterior longitudinal ligament and intervertebral disc
  • Neurologic sequelae rare but possible
• Shear injuries (translational injuries):
  • Anterior, posterior, or lateral translation of superior vertebral segment over the inferior segment
  • Complete ligamentous disruption
  • Neurologic deficit present
• Simple fractures:
  • Isolated spinous process fracture:
    • Ligamentous disruption
    • No neurologic deficit
  • Isolated transverse process fracture:
    • Ligamentous disruption
    • Neurologic deficit possible; rare isolated root injury

Etiology

• Motor vehicle accidents (MVA)
• Fall from height landing on the feet (associated calcaneal fractures) or on the buttocks
• Blunt trauma with axial distraction, axial compression, or translational forces applied to lumbar region
• Penetrating injury: Primary gunshot wound

• Rare reports of child abuse presenting as lower extremity flaccid paralysis owing to lumbar spine fracture
• Spinal cord terminates at L3 in newborn and recedes to T12 by adulthood; direct cord damage possible in children with high lumbar fractures
• End plate avulsion fractures: Adolescent injury usually at L4–L5 or L5–S1 level; ligament pulls off vertebral body end plate; associated neurologic findings