Computed Tomography-Based Feasibility Study of C1 Posterior Arch Crisscrossing Screw Fixation
- Author:
Gururaj SANGONDIMATH
1
;
Abhinandan Reddy MALLEPALLY
;
Suman SALIMATH
Author Information
- Publication Type:Clinical Study
- From:Asian Spine Journal 2020;14(3):298-304
- CountryRepublic of Korea
- Language:English
-
Abstract:
Methods:A 100 computed tomography (CT) scans of cervical spines with 1 mm slice thickness in the axial and sagittal sections obtained were randomly selected for the evaluation. Atlantoaxial anomalies due to trauma, deformities, infections, and tumors were excluded. All the images were measured for height of the posterior tubercle, width of the posterior arch, and length of the screw, and the screw projection angle was calculated. Demographic data were collected for all the subjects.
Results:Out of the 88 CT scans analyzed, the mean height of the posterior tubercle was 7.4 mm, wherein 84.09% exceeded 7 mm, and the width of the posterior tubercle was 5.4 mm, wherein 88.6% (n=78) had posterior arch width >3.5 mm. A total of 13.6% (n=12) vertebrae were not suitable for screw placement, whereas 75% (n=66) vertebrae could accommodate 3.5×15 mm or longer screws. The screw projection angles ranged from 11.2° to 35° on the right and from 15.6° to 38.2° on the left.
Conclusions:C1 posterior arch screw fixation is a feasible and safe method because it poses little risk of injury to the surrounding neurovascular structures.
