Radiographic Evaluation Of Cervical Spine
By Dr. KM Liau
This lecture is intended to familiarize students with both normal and abnormal findings of cervical spine X rays used in the trauma room for adult multiple trauma patients.
Most commonly used initial set of X rays
The Big Three
1. Cross table lateral, AP and odontoid (open
mouth)cervical spine X ray
2. Supine chest X ray (AP)
3. AP Pelvis X ray
1. Cross table lateral, AP and odontoid (open
mouth)cervical spine X ray
2. Supine chest X ray (AP)
3. AP Pelvis X ray
Approach to X ray interpretation
1. Know how normal anatomy appears on X ray
2. Always take a systematic approach to X ray
interpretation
3. A little distance can be a good thing
4. Experience counts
2. Always take a systematic approach to X ray
interpretation
3. A little distance can be a good thing
4. Experience counts
Cervical Spine X rays
The lateral film
Criteria for adequacy
a. Is there anything obscured by jewelery or other
opaque objects?
b. Is the X ray penetration appropriate?
c. Must be able to see at least the top half of T1 at the lower aspect and the occiput and palate at the superior aspect.
a. Is there anything obscured by jewelery or other
opaque objects?
b. Is the X ray penetration appropriate?
c. Must be able to see at least the top half of T1 at the lower aspect and the occiput and palate at the superior aspect.
Cervical Spine X rays
The lateral film
Three curves to follow
a. Anterior aspect of vertebral bodies
b. Posterior aspect of vertebral bodies
c. Spinolaminar line
a. Anterior aspect of vertebral bodies
b. Posterior aspect of vertebral bodies
c. Spinolaminar line
Cervical Spine X rays
The lateral film
Abnormalities in the curves
1. Posterior malalignment is more significant than
anterior because of proximity of the spinal cord
2. Spinal canal diameter is significantly narrowed
if < 14 mm
3. Anterior subluxation is caused by facet
dislocation
A) < 50% of vertebral body width = unilateral
dislocation
B) > 50% of vertebral body width = bilateral
dislocation
1. Posterior malalignment is more significant than
anterior because of proximity of the spinal cord
2. Spinal canal diameter is significantly narrowed
if < 14 mm
3. Anterior subluxation is caused by facet
dislocation
A) < 50% of vertebral body width = unilateral
dislocation
B) > 50% of vertebral body width = bilateral
dislocation
Cervical Spine X rays
The lateral film
Examine bones for symmetry
1. May provide evidence of fracture
2. Abnormal symmetry is often due to compression
a) Compression of > 40% of normal vertebral body
height usually indicates a burst fracture with
possibility of bone fragments in the spinal
canal
b) Anterior compression may cause a "teardrop" shaped fracture
1. May provide evidence of fracture
2. Abnormal symmetry is often due to compression
a) Compression of > 40% of normal vertebral body
height usually indicates a burst fracture with
possibility of bone fragments in the spinal
canal
b) Anterior compression may cause a "teardrop" shaped fracture
Cervical Lateral Film - Measurements
1. Retropharyngeal/retrotracheal space
a) 6 mm at C2
b) < 50% of width of vertebral body at C4 and below
(Easy to remember- 6 at 2; 2 at 6; which means 6 mm at C2 and 20 mm at C6)
Abnormal measurements may indicate soft tissue swelling from obvious or occult fractures, haematomas, or abscesses.
a) 6 mm at C2
b) < 50% of width of vertebral body at C4 and below
(Easy to remember- 6 at 2; 2 at 6; which means 6 mm at C2 and 20 mm at C6)
Abnormal measurements may indicate soft tissue swelling from obvious or occult fractures, haematomas, or abscesses.
Cervical spine - normal lateral view
Cervical Lateral Film - Anterior Atlanto-Dens Interval
1. 3 mm in adult (5 mm in children)
2. > 3.5 mm indicates injury to transverse ligament
3. > 5 mm indicates complete transverse ligament rupture and instability
Rule of thirds
At the C1 level, the dens, spinal cord, and empty space each occupy about a third of the available space; therefore, there is actually fairly considerable room for swelling, dislocation, and movement.
2. > 3.5 mm indicates injury to transverse ligament
3. > 5 mm indicates complete transverse ligament rupture and instability
Rule of thirds
At the C1 level, the dens, spinal cord, and empty space each occupy about a third of the available space; therefore, there is actually fairly considerable room for swelling, dislocation, and movement.
Cervical Spine X rays
The lateral film
Relationship of occiput to atlas (C1)
a. Distance between occiput and C1 should always be < 5 mm
b. Increased distance may indicate atlanto-occipital disassociation
a. Distance between occiput and C1 should always be < 5 mm
b. Increased distance may indicate atlanto-occipital disassociation
Cervical Spine AP View
Look for:
1. Symmetry and size of vertebral bodies
2. Alignment of spinous processes
3. Smooth, rolling lateral edges
1. Symmetry and size of vertebral bodies
2. Alignment of spinous processes
3. Smooth, rolling lateral edges
Cervical spine - normal AP view
Odontoid (open mouth) view
Anatomy of C1-C2 (atlas and axis)
a. Dens (C2)
b. Lateral masses (C1)
c. Rotation vs. fracture
d. Watch out for those teeth!
a. Dens (C2)
b. Lateral masses (C1)
c. Rotation vs. fracture
d. Watch out for those teeth!
Normal open mouth view
Abnormal cervical spine films
1. Atlanto-occipital disassociation
2. Dislocations
3. C1 and C2 fractures
3. Other cervical fractures
2. Dislocations
3. C1 and C2 fractures
3. Other cervical fractures
Hangman fracture - bilateral pedicle or pars fracture of C2 with anterior subluxation of C2 over C3
C2 pedicle fracture
C7spinous process fracture - Clay Shoveler's fracture
Trauma Radiology Link List
- brighamrad.harvard.edu
- General radiology resource
- chorus.rad.mcw.edu
- Collaborative Hypertext of Radiology (Medical College of Wisconsin), general radiology resource
- rmstewart.uthscsa.edu
- Univ. of Texas Health Sciences Center, trauma case studies with great references
- www.swahs.nsw.gov.au
- Liverpool Hospital of Univ. of New South Wales, Australia, great trauma case studies, trauma X rays, discussion list
- trauma.orhs.org
- Orlando Regional Medical Center, case studies with X rays
- www.trauma.org/
- Fantastic general trauma and injury prevention resource, includes case studies, extensive X rays, subscribe to Trauma email list
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