emergency spinal radiological assessment

Emergency Spinal

Radiological Assessment

spine injury: location

type neurologic sequelae

1. cervical . . . . . . brainstem, cord or root

2. thoracic . . . . . cord or root

3. lumbar . . . . . . conus or root

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cord injury: deficit patterns

1. normal (no neurologic injury)

2. incomplete deficit (syndromes)

a. central cordb. anterior cord c. Brown-Sequardd. posterior corde. conus/epiconus

3. complete functional transection

spine injury: types

1. muscular/ligamentous

a. contusionsb. strainsc. sprainsd. complete ligamentous disruption

2. fractures

+ / - dislocation

stability: 1. stable 2. unstable

spinal Imaging after trauma - indications

1. clinical indications

a. spine-region pain b. neurologic deficit

(1) radicular(2) cord

c. severe multisystem injuries d. altered mental status

2. clinical rationale

a. prevent cord, root injury (neurologic stability) b. prevent incapacitating deformity and pain

(mechanical instability)

Which patients need imaging of the cervical spine?

Case 1: mild/moderate trauma patient

– no loss of consciousness– normal mental status (and not intoxicated)– no neck pain or tenderness – no neurologic deficit

no imaging needed

Which patients need imaging of the cervical spine?

Case 2: mild/moderate trauma patient

– altered mental status (patient is obtunded and/or intoxicated)

– neck pain or tenderness – neurologic symptoms or deficit

Which patients need imaging of the cervical spine?

Case 3: severe multi-system trauma patient

imaging needed

spinal Imaging after trauma – imaging tools

1. bony - fractures/dislocations

a. X-rays – AP, lateral, open-mouth odontoid b. CT scan

2. ligamentous

a. MRI scan b. flexion – extension lateral x-ray

3. disk injury

a. MRI scan b. CT/myelogram

cervical: 7 lordotic curve

thoracic: 12kyphotic curve

lumbar: 5lordotic curve

spine injury: alignment

1. pre-vertebral fascia

2. anterior marginal line

3. posterior marginal line

4. spino-laminar line

5. posterior spinous line

A. vertebral body width

B. spinal canal diameter

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ligamentous injury without fracture

instability possible even with normal CT; early MRI helpfulstabilize until neck pain resolves, assess competence of

ligaments with flexion/extension X-rays or MRI

Bilateral facet fracture/dislocation:“jumped” or locked facets

C1 - Jefferson fracture

axial loadingoften associated with

C2 fracturesassess transverse ligament

type I

type II

type III

C2 - odontoid fractures/subluxations

C2 - Hangman’s fracture

hyperextension/axial loading

bilateral C2 pars interarticularis fracture

unstable when:a. >3.5 mm subluxation of

C2 on C3b. >11 degrees angulation

Atlantoaxial subluxation

• Atlantodental interval (ADI)

• Left: Normal ADI ≤ 3 mm

• Right: C1-2 subluxation

Denis 3-column model - thoracolumbar spine

one-column injury usually stable

two-column injury usually unstable

three-column injury unstable

Class A: vertebral body compression

compression fractureAnterior column failureMiddle and posterior columns intactUnstable if >50% compression or

>20 degrees angulation

burst fractureAnterior and middle column failureRetropulsion of bone into canalOften have neurologic deficitUnstable

Burst fracture

Class B: distraction (+ flexion/extension)

Types Flexion/distraction (Chance, seat belt injury)Hyperextension

Three-column injury: unstable

flexion/distractionposterior ligamentous injury

Class C: three-column injury with rotation

fracture-dislocationshear injury

unstable

neurologic deficit

fracture-dislocation