Vertex Select Flashcards
What is the drilling/screw trajectory for C1 lateral mass?
Should be straight or 5-10 degrees convergent medial, and angle cephalad parallel to the underside of the posterior arch.
What is the entry point for C2 pedicel screws?
3-4mm above the C2 inferior facet
What is the Entry point for C2 pars screw?
3mm superior to the C2/C3 facet joint line and 3mm lateral to the lamina/lateral mass junction.
What is the trajectory for C2 pedicel screws?
20-30 degrees medial directed at the central axis and 20-30mm cephalad
What is the trajectory for C2 pars screws?
10-15 degrees medial and 35 degrees cephalad (aiming under floro at the C1 tubercle)
What is the entry point for C3-C7 lateral mass screws?
1mm medial to the center of the lateral mass (outlined by box method:superior to inferior facet join and lamina/lateral mass junction to lateral edge of the lateral mass)
What is the trajectory of C3-C7 lateral mass screws?
Place perpendicular to the lateral mass then angle 20-30 degrees lateral and 20-30 degrees cephalad
What is the entry point for C3-C7 pedicle screws?
Just lateral of the midpoint of the lateral mass and 2-3mm below the inferior facet margin of the cephalad vertebra
What is the trajectory for C3-C7Pedicle screws?
25-45 degrees medial towards the midline and angled slightly cephalad
What is the entry point for C1 lateral mass screws?
Middle of the junction between C1 Posterior arch and the midpoint of the posterior inferior part of C1 lateral mass.
What size diameter are the Vertex MAS
3.5mm, 4.0mm and 4.5mm
What is the length of Vertex 3.5 MAS
10mm-34mm (2mm increments)
36mm-40mm (order extra)
What is the length of Vertex 4.0 MAS
10mm-34mm (2mm increments)
36mm-52mm (order extra)
What is the length of Vertex 4.5 MAS
24-34mm (2mm increments)
10mm-22mm and 36mm-52mm (order extra)
What size diameter of partially threaded MAS are in Vertex
3.5mm and 4.0mm