Abstract: Objective To explore the factors related with bladder function after surgical intervention in patients with first lumbar burst fractures uniting isolated conus medullaris syndrome (CMS). Methods 25 patients complicated CMS in 618 patients with Ｌ₁ burst fracture were analyzed retrospectively. Results The recovery rate of patients with saddle sensation weakness was higher than the patients with saddle sensation disappeared (P<0.05). There was no difference in bladder function between patients accepted surgery within 2 weeks and more than 2 weeks (P>0.05). Conclusion Saddle sensation before surgery related with the recovery of bladder function.

Key words: thoracolumbar fracture, spinal cord injury, conus medullaris injury, spinal surgery, bladder function, saddle sensation