SUMMARY A patient with previous L3 -4 posterior lumbar interbody fusion,pedicle screws instrumen-tation and L3 -4 decompression,was scheduled for left total hip arthroplasty.Two years ago,due to poor landmarks palpation,the patient experienced a failed lumbar puncture after multiple attempts before her-niorrhaphy.His plain radiography showed bilateral partial laminectomy at L3 -4 level,and between L3 and L4,two posterior pedicle screws connected by metal rods on both sides.This time,we used ultra-sound to locate L4 -5 interlaminar space in paramedian sagittal oblique view and identified the spine midline by transverse interlaminar view before puncture.According to this information,L4 -5 puncture point was verified and the combined spinal-epidural anesthesia was performed in a paramedian approach. After withdrawing clear cerebral spinal fluid,15 mg hyperbaric bupivicaine was injected into intrathecal space.An epidural catheter was then inserted into the epidural space.The sensory block level was fixed at T10

作者：耿姣；李民

来源：北京大学学报（医学版） 2016 年 48卷 4期