Chance fracture

Background

• Unstable
• Most common at T12-L2 due to spinal curvature and mechanism
• May be misdiagnosed as anterior compression fracture, which is usually stable

Clinical Features

• Common mechanism: seat belt serves as axis of rotation with failure of middle and posterior columns
• Seat Belt Injury: lap belt worn above the pelvic bones without a shoulder harness
• Mechanism: minor anterior vertebral compression with failure of the middle and posterior columns
• Intra-abdominal injuries more commonly associated than neuro deficits

Evaluation

Chance fracture of T10 and fracture of T9 due to a seatbelt during an MVC on xray.

Chance fracture of T10 and fracture of T9 due to a seatbelt during an MVC on CT.

Workup

• Obtain sagittally reconstructed CT if suspect lap-belt mechanism or flexion-distraction

Diagnosis

• Pure bony injury from posterior to anterior through:
  • Spinous process
  • Pedicles
  • Vertebral body

See Also

• Thoracic and lumbar fractures and dislocations