Abstract
Objectives
Using computed tomography, it is to measure pedicle size of lower cervical spine in Koreas to find ideal insertion point and angle in fixating pedicular screws.
Summary of Literature Review
Although techniques in pedicular screw fixation and pedicle's anatomical shape in foreign populations have been well documented and studied, no anatomical study on lower cervical pedicle in Korean population has been reported.
Materials and Methods
A total of 180 patients with computed tomography taken at our institution were selected for the study. Width, total length, and length of pedicle, insertion point and angle, and safe insertion angles were measured on axial view. On sagittal view, height of pedicle, insertion point and angle, and safe insertion angles were determined.
Results
Mean height of study subject was 164.2cm. Mean width of pedicle was 5.5mm, mean height 7.2mm, mean total length 31.2mm, and mean length 14.8mm. Mean insertion point from 3 rd to 7 th cervical spines was medially 3.3mm from lateral mass and downward 4.7mm from margin of upper facet. Mean insertion angles from 3 rd to 7 th cervical spines were 41.6° axially and 6.4° sagittally. Calculated safe insertion angles were 8° on medial and lateral sides and 14° on superior and inferior sides.
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