> [!Key Points] > 1. look for subtle vertebral body cortex angulation and disruption of the trabeculae > 2. is the posterior vertebral body margin involved? (does it involve the middle column) > 3. Assess the interspinous distance and facets for posterior column injury > 4. Assess the canal for cord injury - **Chance** fracture usually caused by lap belt injury. - **Burst** fracture usually caused by axial loading mechanism. - **Teardrop** fracture usually caused by hyperflexion or extension injury. - **Wedge** fracture usually caused by any of the above mechanism and more common in elderly patients. # Three columns of stability ![[Pasted image 20230413181955.png|Anterior, middle, and posterior columns]] **Anterior column** - anterior longtudinal ligament and most of the vertebral body (anterior 2/3), anterior fibres of anulus and nucleus pulposis **middle column** - involves the **posterior cortex** of vertebral body. also posterior fibres of anulus fibrosis, and posterior longitudinal ligament **posterior column** - everything behind posterior longitudinal ligament: pedical, lamina, facet joints, spinous process, interspinous ligament, supraspinous ligament, and ligamentum flavum (inside of the lamina). ![[Pasted image 20230413182811.png]] **generalisations** > - a single-column injury is usually stable > - if the middle column is involved, there is usually a 2 or 3 column injury > - If two columns are involved **at the same level**, then you can imply instability # Guidelines on imaging of spine Eastern guidelines Level 1 - if imaging required, than CT should be used Level 2 - screen if tender, neuro deficit, ALOC, intoxicated, "distracting" injury, high energy Level 2 - screen if known or suspected cervical injury > only use X-ray if lacking access to CT # False positives ## Limbus vertebrae ![[Pasted image 20230413184725.png| well-corticated unfused secondary ossification center of the vertebral body, usually of its anterosuperior corner, that occurs secondary to herniation of the nucleus pulposus through the vertebral body endplate beneath the ring apophysis]] - occurs when there is disc herniaation down through end plate, works to isolate anterior-superior corner - an intra-vertebral body herniation of the disc material occurring during adolescent growth spurt when the ring apophysis has not yet fused not a fracture because: 1. smooth 2. well-corticated 3. volume of vertebral body has not changed 4. no other signs of trauma (eg perivertebral haematoma, etc) ## Veins ![[Pasted image 20230413185718.png| Note that the dark part on the posterior of the vertebral body is where the veins enter the vertebral body]] - usually more prominant as you go down the spine - can mimic fractures ## old fractures ![[Pasted image 20230413190525.png]] # Fractures ## Chance fracture ![[Pasted image 20230413193216.png]] ^ caused by hyperflexion over a fixed pivot point . - classic location T12, L1, or L2 - anterior column failure under compression - middle and posterior column failure under distraction - 3 column injury is **unstable**, concern for spinal cord injury - Needs MRI to assess these structures and for peri-neural haematoma - fracture pattern is associated with retroperitoneal injury (pancreas, duodenal, adrenal, sometimes aortic) ## burst fracture with anterior and middle column fracture with retropulsion ![[Pasted image 20230413194942.png]] ^ L1 two column unstable fracture - displacement of fracture fragment back into spinal canal - caused by high energy compressive **axial loading** another view: ![[Pasted image 20230413195142.png]] Axial view: ![[Pasted image 20230413195257.png]] ^ **burst fracture** because burst from vertebral body MRI of a different case of a burst fracture showing retropulsion and extensive involvement of canal: ![[Pasted image 20230413195451.png]] ^ cauda equina nerve roots being compressed; would present as a [[cauda equina syndrome]] ## Facet subluxation ![[Pasted image 20230413194150.png]] ^ there should be ~1cm of overlap between superior and inferior articular facet processes. Here they are separated a bit --> subluxed ## fracture dislocation Facets will likely be in alignment Look for [[Neck and spine trauma#anterior cord]] syndrome # CT Vs MRI ![[Pasted image 20230413193311.png]] ^ subtle findings on this CT, some separation between T11 and T12 spinous process, some induration and lucency noted in L1 and L2 ?fracture involving middle column, and anterior superior endplates suspicious for fractures However, we can appreciate significant injuries on the MRI scan: ![[Pasted image 20230413194346.png]] ^ marrow oedema, also significant oedema and tear through ligamentum flavvum (as well as interspinous ligament tear) to account for separation of spinous processes. this is a multicolumn **unstable** injury! #trauma #radiopaedia