Knowledge of the normal range about the position of the lower end of the conus medullaris and the dural sac is very useful in diagnosing tethered spinal cord syndrome and in locating lumbar puncture site.

• 熟悉脊髓圆锥和硬膜囊下端位置的正常范围 ,能帮助临床诊断脊髓栓系综合征等疾病及腰椎穿刺定位。