Cervical Spine

Question 1

measurements for the basion-dental interval and atlanto dental interval

Answer 1

basion-dental interval < 12 mm

atlanto-dental interval
atlanto-axial interval
should be <2.5 mm in adults should be <5 mm in children

Question 2

4 primary osseous lines?

Answer 2

anterior vertebral, posterior vertebral, spinolaminar, spinous process

Question 3

jefferson fracture?

Answer 3

axial blow to head with symmetrical fracture of the anterior/posterior arch

Question 4

XR findings of jefferson fracture on odontoid view

Answer 4

lateral displacement of C1 lateral masses

Question 5

MOA for C2 odontoid fractures?

Answer 5

flexion injuries

Question 6

3 types of dens fractures

Answer 6

I: fracture of distal tip of dens; stable
II: fracture of base of dens
III: fracture of base of dens extending into C2 vertebral body

Question 7

ddx for type I dens fracture

Answer 7

os odontoideum

Question 8

traumatic spondylolysis of C2; fractures through pedicles

Answer 8

hangmans fracture

Question 9

MOA hangmans fracture

Answer 9

hyperextension/distraction

Question 10

XR finding hangman’s

Answer 10

spinolaminar line

Question 11

> 3mm displacement of C2 on C3 concern?

Answer 11

unstable

Question 12

burst fracture location?

Answer 12

similar to jefferson’s; C2-C7

Question 13

flexion teardrop fracture MOA?

Answer 13

hyperflexion/compression injury with posterior displacement of vertebral bodies

Question 14

radiographic findings of flexion teardrop/

Answer 14

avulsed bone fragment from anterior-inferior vertebral body (ALL avulsion); retropulsion of vertebral body/rotation

Question 15

severe clinical presentation of flexion teardrop

Answer 15

anterior cord syndrome (compression pyramidal/anterior spinothalamic tracts)

Question 16

extension teardrop fracture

Answer 16

stable fracture in C2/C3

anterior/inferior avulsion fragment without subluxation or disruption of spinolaminar line

Question 17

clay shoverler’s fracture

Answer 17

displaced avulsion fracture of spinous process; forced flexion

lower cervical spine/upper thoracic spine C6-T1

Question 18

bilateral interfacetal dislocation/locked facets

Answer 18

hyperflexion injury, disruption of all lines and anterior dislocation of affected vertebra; lower cervical spine

high risk of cord damage

Question 19

naked facet

Answer 19

superior articular facets not covered by inferior facets

Question 20

perched facets

Answer 20

anterior subluxation >3mm but less than 50% seen in complete dislocation

Question 21

unilateral interfacetal dislocation

Answer 21

hyperflexion with rotation opposite site of dislocation (stable)

Question 22

Grisel syndrome

Answer 22

nontraumatic rotary subluxation of atlantoaxial joint due to inflammation (pharyngitis, retropharyngeal abscess); commonly peds