RT Journal Article SR Electronic T1 The shape of the human lumbar vertebral spinal canal JF Regional Anesthesia: The Journal of Neural Blockade in Obstetrics, Surgery, & Pain Control JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 27 OP 27 DO 10.1136/rapm-00115550-199318011-00027 VO 18 IS Suppl 1 A1 Edmundo Zarzur YR 1993 UL http://rapm.bmj.com/content/18/Suppl_1/27.abstract AB