Spinal XRs

Trauma: Spinal XR

C-Spine

Adequacy
Lateral: base of skull, 7 vertebrae, and sup. T1
- imay need a swimmer's view for C7/T1 jx.
Odontoid: entire odontoid and C1,C2 articulations.

Alignment
4 lordotic curves:
- anterior vertebral bodies
- anterior spinal canal
- posterior spinal canal
- spinous process tips
* look for loss of alignment and narrowing of canal

Bone
Vertebrae contour and axial height.
Lateral bony mass: pedicles, facets, laminae, transverse processes
Spinous processes
* look for deformity, #

Cartilage
Intervertebral discs
Posterolateral facets

Soft-tissue spaces
Prevertebral space (>5mm opposite C3)
Prevertebral fat stripe
Space between spinous processes (torn ligaments).
* look for enlarged prevertebal space or increased distances between spinous processes.

AP film
Most useful in identifying unilateral facet dislocations where nil seen on lateral film.

T/L spine

Anteroposterior
Alignment
Symmetry of pedicles
Contour of bodies
Height of disc spaces
Central position of spinour processes

Lateral
Alignment
Contour of bodies
Presence of disc spaces
Encroachment of body on canal.

Notes
* Unstable #s commonly cause widening of the interpedicular distance
* Lateral films show subluxations, compressions and Chance #s
* CT is better for posterior #s, canal compromise in burst #.

Considerations in Paeds

Pseudosubluxation complicates c-spine evaluation
- 40% of children <7 have C2 on C3 anterior displacement
- 20% up to 16 yrs
- less commonly at C3-4.
- >3mm of movement seen here when jts studied by flexion/extension maneuvers.

To determine if pseudosubluxation vs true injury:
- place child's head in neutral position and repeat XR (pseudo is more pronounced in flexion)
- compare with clinical findings.

Increased dens-C1 anterior arch distance increases in ~20% of young children.
- gaps exceeding noral adult limits are seen frequently

Skeletal growth plates can resemble fractures
- basilar odontoid synchondrosis appears as a radiolucent area at base of dens in children <5
- apical odontoid epiphyses appear as separations on the odontoid XR and are usually seen at 5-11yrs.
- growth centre of spinous process may resemble a # at the tip.

SCIWORA
Spinal cord injury without radiogaphic abnormality is more common in kids
- 2/3 of children with spinal cord injury have a normal spine series
Spinal XRs do not exclude significant spinal cord injury
Assume instability
Maintain immobilisation
Obtain consult