Objective: to investigate the X-ray projection of acetabulum on its anterior and posterior column and to develop a safe area for screw placement.
目的：探讨髋臼在其前、后柱上的投影和螺钉放置的安全范围。
2
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。
3
A posterior malleolar fracture is seen on the lateral projection (FIG. 6b), establishing a complete (stage IV) injury.