1.Posterior First and Second Cervical Vertebrae Fusion by Screw Fixation Technique using the Modern Pre-fabricated Template Method on Cadaver Samples
Athari M ; Golbakhsh MR ; Mirbolook A ; Athari M ; Ahmadi A ; Komlakh K ; Azarhomayoun A ; Paydarniya P
Malaysian Orthopaedic Journal 2021;15(No.3):58-64
Introduction: C1 lateral mass and C2 pedicular screws
insertion are used for C1-C2 posterior fusion. Fluoroscopy
Guided technique is routinely used for screw placement but
it is associated with risk of injury to spinal cord and vertebral
artery. 3D printing has developed rapidly in the fields of
medicine. It is helpful in improving precise treatment and
used for instrumentation in spine. We want to evaluate the
accuracy of C1 lateral mass screws and C2 pedicle screws
insertion by Pre-Fabricated Template made by threedimensional (3D) printing.
Materials and methods: Five cervical samples were
obtained from cadavers. Based on fine-cut CT scan 3Dimages reconstructed and the path of the screws designed by
special software. A template produced by 3D-printer from
3D images. After printing the templates, they were fixed on
the relevant vertebra in the operation room and based on the
template path, C1 lateral mass screw and C2 pedicular
screws were inserted. Placement of the screws was evaluated
using CT scans post-operatively.
Results: A total of 14 screws were inserted by abovementioned method. After evaluation with CT scans none of
the screws were entered in the spinal canal. Two screws had
vertebral artery canal perforation with less than 50% breach.
Violation was judged as noncritical and would probably not
have resulted in injury to vertebral artery.
Conclusions: The accuracy of C1 lateral mass screw and C2
pedicle screw insertion is acceptable with pre-fabricated
template and can provide a useful aid for screw placement.