Related Experiment Video
Updated: Jan 27, 2026

C-arm-Free Simultaneous OLIF51 and Percutaneous Pedicle Screw Fixation in a Single Lateral Position
Published on: September 16, 2022
Axis screws: results and complications of a large case series
Cleiton Formentin1, Erion Junior de Andrade1, Fernando Luis Maeda1
1Resident - Neurosurgery Division - Department of Neurology, University of Campinas (UNICAMP), Campinas-SP, Brasil.
Objective:
To present the surgical results of patients who underwent axis screw instrumentation, discussing surgical nuances and complications of the techniques used.
Methods:
Retrospective case-series evaluation of patients who underwent spinal surgery with axis instrumentation using screws.
Results:
Sixty-five patients were included in this study. The most common cause of mechanical instability was spinal cord trauma involving the axis (36 patients - 55.4%), followed by congenital craniocervical malformation (12 patients - 18.5%). Thirty-seven (57%) patients required concomitant C1 fusion. Bilateral axis fixation was performed in almost all cases. Twenty-three patients (35.4%) underwent bilateral laminar screws fixation; pars screws were used in twenty-two patients (33.8%), and pedicular screws were used isolated in only three patients (4.6%). In fourteen patients (21.5%), we performed a hybrid construction. There was no neurological worsening nor vertebral artery injury in this series.
Conclusion:
Axis screw instrumentation proved to be a safe and efficient method for cervical stabilization. Laminar and pars screws were the most commonly used.
Related Concept Videos
Self-Locking Screw
A square-threaded screw jack carrying a load is considered self-locking if the screw retains its position even after the moment applied to it is removed.
Screw: Problem Solving
To evaluate the...
Hypothalamic-Pituitary Axis
Frictional Forces on Screws
A jack with a square-threaded screw is a mechanical device used to lift heavy loads by applying a force at its handle. When the force is applied, the screw turns, raising the load. The screw can...
Resistors In Series
In a series circuit, the...
Perpendicular-Axis Theorem
Consider a circular disc of mass M and radius R lying along an x-y plane. The origin lies at the center of the disc, and the z-axis is perpendicular to the disc's plane. All three axes coincide at the disc's center. The moment of inertia of this...

