Abstract: Objective Patients suffered ankylosing spondylitis with high risk of general anesthesia were given combined spinal epidural anesthesia（CSEA） under ultrasound guidance.Methods A 51-year-old male for open reduction and internal fixation was scheduled.The patient had a history of ankylosing spondylitis.The lumbar，thoracic and cervical spine has some difficulties in extension and bending.CSEA was conducted with the guidance of ultrasound.Results The pilot ultrasound scanning indicated that the L3/4 intralaminar space existed，and then CSEA was successfully performed with ultrasound guidance.The patient was discharged from hospital one week later and no anesthesia-associated complications occurred.Conclusions CESA under ultrasound guidance greatly facilitates the difficulty of intravertebral puncture in patients with ankylosing spondylitis.

Key words: lower extremities, surgery;spinal block;ankylosing spondylitis;ultrasound guidance