- See:
-
Flexion and Extension Views:
-
Technique:
- Upper Cervical Spine:
-
prevertebral soft tissues
-
occipital-atlanto-axial injury:
-
atlanto-occipital disassociation
- C1-C2 interspinous space should not be greater than 10 mm;
-
atlanto-axial impaction (
rheumatoid C-spine)
-
atlas (
Jefferson frx)
-
axis (
odontoid frx /
hangman frx)
- atlantoaxial distance & SAC;
-
ADI in children (< 10 yrs) < 3.5 mm; (see
pediatric C-spine)
-
ADI in adults < 3 mm;
- an anterior shift of C1 on C2 of more than 3-5 mm implies injury to
transverse ligament (see
atlanto-axial subluxation);
- shift > 5 mm implies injury transverse & alar ligaments;
- SAC:
- greater than 18 mm is normal normal;
- 15-17 mm - grey zone;
- less than 14 mm is consisent w/ cord compression;
-
pseudosubluxation of c spine:
- Sub-Axial Spine - Alignment:
-
posterior cortices: (more important than anterior cortices)
- anterior or posterior translation of vertebral bodies > 3.5 mm implies instability;
- w/ less than 25% relative shift of one vertebral body over another consider
facet frx;
- w/ 25% relative shift consider
unilateral facet dislocation and w/ 50% shift, consider or
bilateral facet dislocation;
-
vertebral body angulation / translation:
- patterns of instability include:
- 1.7 mm or greater of disk widening;
- 3.5 mm of translational displacement;
- angulation between two adjacent vertebra of 11 deg more than contiguous cervical vertebrae;
- measurements are made from each inferior endplate;
-
anterior cortices:
-
anterior subluxation
- minimal
compression frx of anterior vertebral bodies;
-
tear drop sign: bone chip off antero-inferior aspect;
- may indicate displacement of disc or posterior fragment of vertebral body into spinal canal & cord injury;
-
spinolaminar line (dorsum of lateral masses) (see
oblique view);
-
facet joint widening;
- rotation of the facets on
lateral view;
- parallel articular process facets;
-
spinous process angulation:
- C1-C2 interspinous space should not be greater than 10 mm;
- widening is present when the distance is more than 1.5 times the inter-spinous distance of adjacent spinal segments;
- fanning implies
middle column disrupton;
Biomechanical analysis of clinical stability in the cervical spine. Clin Orthop Rel Res. 1975; 109: 85-96. White A., Johnson R., Panjabi M., and Southwick W.
Neurapraxia of the cervical spinal cord with transient quadriplegia. J Bone Joint Surg (Am) 1986;68A:1354-1370. Torg JS, Pavlov H, Genuario S, et al:
