目的：比较不同牵引方向对颈椎间盘突出症(PCD)的颈椎形态结构的影响。方法：借助MRI影像扫描分析不同牵引方向对突出间盘的运动、脊髓受压指数、椎间隙的变化及伴有变性病例的影响。结果：各种牵引方向对间盘突出的作用是不同的，屈曲牵引使间盘部分还纳最为明显；脊髓受压指数在屈伸方向牵引最低；伸展牵引时间盘突出缩小组的后缘椎间隙减小明显；屈曲牵引时间盘缩小组与无变化组的后缘变化差异不大，两种牵引方向对前缘影响均无差异；各种方向牵引伴有变性者的形态变化不明显。结论：PCD改变了正常椎关节的微细形态结构，对常规牵引方向的规律宜灵活运用；脊髓受压指数比间盘突出大小更能反映脊髓受损的实质；牵引对伴有变性者影响可能不大。“,”Objective The purpose of this study was to compare the functional and morphological changes in the cervical spine with protrusion of cervical disc (PCD) under different directions of traction. Methods MRI scanning was used to study the effect of different directions of traction on the movement of protrusive disc，compression index of spinal cord and changes of intervetebral space,as well as the cases with degeneration. Results　Differences were found in the effect of different directions of traction. Most significant partial reduction of the protrusive disc was experienced in flexion traction. Both flexion and extension traction caused significant decrease in the index of compression of spinal cord. Extension traction caused marked narrowing of the posterior intervertebral space in the group with decreased disc size,while no difference between the groups with and without decreased disc size when given flexion traction. There was no difference in the anterior intervertebral space between the two directions of traction. No morphological change was observed in cases with degeneration using either direction of traction. Conclusion PCD could caused the change in the fine morphology of normal vertebral joints. The traction direction should be chosen according to the condition of the individual case. The compression index could better reflect the nature of spinal cord injury than the size of the disc protrusion. Traction would not give much benefit in cases with degeneration.