APOM/ vertico-horizontal Flashcards
Why is the projection name vertigo-horizontal?
b/c the central ray is projected between the vertical and horizontal film.
Why is the mouth open on this film?
To easily view the occipital-atlantal-axial complex
What is the primary purpose of this film?
Complete axis listing
What is the secondary purpose of this film?
The assumed atlas listing
What does the assumed atlas listing consist of ?
The last two letters of the listing.
How is the assumed atlas listing derived?
From the applicable 70% finding
The distance when taken is?
40”
The lines are exactly like which film? Except for which line?
Nasium
SBL
Why is the SBL different?
Constructed differently
How do you draw the OOL?
Find like dots in orbit and draw line.
How is SBL constructed.
Place dots on jugular processes. Draw line
If jugular processes are obscured, how would you draw the SBL?
Radio-dense area of the occiput.
Where on the radio-dense area of occiput would you draw these?
Base of occiput, lateral to the condyle. “V’s” coming off the occiput.
Where are the jugular processes?
Lateral to the condyles
The jugular processes serve as insertion point for which muscle?
Rectus capitis lateralis
The rectus capitis lateralis originates from where?
Atlas transverse process.
How is IBL drawn?
Lateral inferior tips of lateral masses, draw line
Where is the + drawn from?
Btw condyle tips
The + represents what?
Center of neural canal.
Before drawing the VML what should you do?
Place dots on center base of odontoid and where lamina meets on superior aspect of spinous process.
How do you draw VML?
Place parallel perpendicular to OOL and draw through center of + sign to the IBL.
How do you determine spinous rotation component of listing?
Compare bottom dot to top dot of odontoid.
What will the spinous listing be?
Either spinout right/left - body pivot
How do you determine entire segment component?
Compare top dot to VML
What is ES listing look like?
ESL or ESR
How do you determine major component?
Compare distance from spinous to odontoid dot to the distance from odontoid dot to VML.
How do you show major component on listing?
With an asterisk
How do you get the assumed atlas listing?
Measure the laterality along IBL like you did on Nasium.
Why is it “assumed” atlas listing?
Because were are assuming it is derived from the 70% rule.
What is the 70% rule for APOM?
SBL and IBL converge to the side of atlas anterior rotation and/or SBL and IBL diverge to side of posterior rotation.
If there is a measured laterality and the SBL and IBL are not parallel to one another the finding would be what?
LP, LA, RP, RA
If the SBL and the IBL are parallel to one another and there is a measured laterality, the finding would be what?
R or L
If the SBL and IBL are not parallel and no measured laterality, the finding would be what?
Right side has rotated to the anterior/posterior side or
Left side has rotated to the posterior/anterior
(depending of the side of convergence/divergence - findings must be written out)
When the atlas and the axis rotate in the same direction is what?
A constant
In a content, what should doctor adjust?
Greatest misaligned vertebra.
When the atlas and the axis rotate in opposite directions is what?
A variable
When it is variable which vertebra should be adjusted?
Atlas
If you adjust the axis in a variable situation what happens?
Can increase rotational component of atlas listing putting more torsion on the cord area.
What is it considered if there is no rotation?
non-applicable
