Thoracic and lumbar fractures and dislocations
Pearls
- Stable if two or more of the spinal columns are intact:
- Anterior (anterior longitudinal ligament, annulus fibrosus, ant. half of the vertebral body)
- Middle (posterior longitudinal ligament, posterior annulus fibrous, and post. half of vertebral body
- Posterior (supraspinous and interspinous ligaments, facet joint capsule)
- Unstable if:
- 50% loss of vertebral height
- Kyphotic angulation around the fx:
- >30o for compression fx
- > 25o for burst fx
- Neurologic deficit
Classification
- Wedge compression fracture
- Only unstable if posterior ligament complex ruptures (requires a rotational force)
- Suspect instability and obtain CT if:
- Severe compression (>50% loss of vertebral height)
- Kyphosis >30o
- Rotational component to the injury
- Compression fx at multiple sites
- Posterior cortex abnormality
- Burst fracture
- Unstable
- Can occur with or without injury to posterior elements (posterior involvement increases risk for neuro deficits)
- Be certain not to mistakenly call a burst fracture a wedge fracture
- Obtain CT if unsure
- Flexion-distraction Injuries (lap belt)
- Obtain sagittally reconstructed CT if suspect lap-belt mechanism or flexion-distraction
- Unstable
- Intra-abdominal injuries more commonly associated than neuro deficits
- Chance Fx
- Lap belt worn above the pelvic bones without a shoulder harness
- Forceful flexion at the lap belt > compressive failure of the ant and middle columns
- One or both articular processes fx > upper vertebrae anteriorly dislocates
- Forceful flexion at the lap belt > compressive failure of the ant and middle columns
- Lap belt worn above the pelvic bones without a shoulder harness
- Imaging
- Compression fx + increased posterior interspinous spaces caused by distraction
- Translational
- Massive direct trauma to the back > failure of all 3 columns
- Almost invariably demonstrate neuro deficits
Source
UpToDate