Result the parameters of posterior arch, lateral mass, vertebral artery groove, axis length of screw pass via posterior arch and lateral mass, projection and direction of screw were measured.
结果测量出寰椎后弓、侧块、椎动脉沟、后弓侧块螺钉通道的轴线长度，及后弓进钉点和进钉方向等参数。
2
Result Obtaining the data of the radius of arterial groovevertebral arch, the tuberculum posterius and anterior altantis .
结果得出了椎动脉沟半距、椎弓、寰椎前后结节等结构的测量数据。
3
Objective: to provide anatomical data of vertebral artery groove for clinical?