The Relevant Anatomy Of The Atlas Lateral Mass Screw Fixation

Objecyive: measurement of Chinese atlantoaxial morphometric was performed to assess safety for either two kinds of atlantal lateral mass or transarticular screws.Methods: thirty normal patients (22 male, 8 female) underwent spiral CT of the cervical spine which were transferred to the workstation in order to reconstruct multi-planar reconstruction(MPR).The MPR was used to measure the height and width of posterior arch in the point of vertebra artery overpass, the height of lateral mass benenththe posterior arch and the height and width ofC2 interarticular isthmus.Results: The height of posterior arch in the point of vertebra artery overpasswas 4.54+1.17mm. The width of posterior arch in the point of vertebra artery overpass was 8.69 + 1.12mm. The height of lateral mass benenththe posterior arch was 4.98 +1.07mm. The height of the C2 isthmus was 6.95 +2.24mm. The width of the C2 interarticular isthmus was 6.75 + 1.39mm. There was no statistically significant between the male and female. Nineteen sides (31.67%) had the height of less than 4mm at the posterior arch in the point of vertebra artery overpass.Eight sides(13.33%) had the height of less than 3.5mm at the lateral mass benenth the posterior arch.Nine sides(15%) had interarticular isthmus narrowing under 5mm(height and/or width).There was statistically significant between the group of unsuitability...