CT Case 049
25-year-old male is brought in by ambulance. After a high speed MVA in a stolen car, he attempted to run from the police. He jumped from a 20m overpass… after which point it was fairly easy for the police to catch him.
On arrival to the emergency department he was haemodynamically stable, complaining of neck pain and right thigh pain.
Neurological exam was normal. His right thigh was tender and swollen (confirmed to be a fractured femur on x-ray).
A CT cervical spine was performed
Describe and interpret the CT
CT interpretation
This CT scan shows a burst fracture of the C7 vertebra. The fracture involves the vertebral body and extends into the lamina.
Of concern there is a retro-pulsed posterosuperior fragment in the spinal canal causing mild spinal canal narrowing.
An MRI was subsequently performed to help evaluate cord injury as well as ligamentous injury.
MRI interpretation
MRI T2 weighted images shows hyperintensity (whiter) within the cord representing cord oedema. It also demonstrates a thin anterior epidural haematoma at C7-T1 levels causing mild spinal canal narrowing.
T2 hyperintensity is also seen in the interspinous ligament in the cervical region, this represents oedema secondary to ligament sprain.
Clinical Pearls
Burst fractures are a type of compression fracture due to high-energy axial loading.
The typical mechanism is a fall from height (usually landing on feet) or from an MVA.
This causes a comminuted fracture of the vertebral body with loss of vertebral height.
These fractures will always involve the posterior vertebral body cortex, and retropulsion of the posterior cortex fragments into the spinal canal (as we see here) with risk of spinal cord compression is common.
A cervical burst fracture is always unstable and will require operative repair. Surgery involves posterior decompression and vertebral body fusion.
The Denis classification of spinal fractures is one method of determining stability of fractures.
The vertebral column is divided into three columns (anterior, middle and posterior).
Instability occurs when injuries affect two or more contiguous columns. Applying this to the case here, we see that this is a 3-column injury.
References
- Denis F. The three column spine and its significance in the classification of acute thoracolumbar spinal injuries. Spine (Phila Pa 1976). 1983 Nov-Dec;8(8):817-31
- El-Feky M. Three column concept of spinal fractures. Radiopaedia
- Zhang A, Chauvin BJ. Denis Classification. StatPearls
TOP 100 CT SERIES
Emergency Medicine Education Fellow at Liverpool Hospital NSW. MBBS (Hons) Monash University. Interests in indigenous health and medical education. When not in the emergency department, can most likely be found running up some mountain training for the next ultramarathon.
Dr Leon Lam FRANZCR MBBS BSci(Med). Clinical Radiologist and Senior Staff Specialist at Liverpool Hospital, Sydney
Sydney-based Emergency Physician (MBBS, FACEM) working at Liverpool Hospital. Passionate about education, trainees and travel. Special interests include radiology, orthopaedics and trauma. Creator of the Sydney Emergency XRay interpretation day (SEXI).
Provisional fellow in emergency radiology, Liverpool hospital, Sydney. Other areas of interest include paediatric and cardiac imaging.