RT Journal Article SR Electronic T1 The effect of tramadol added to ropivacaine infusion in femoral nerve blockade for postoperative pain relief during total knee arthroplasty: 190. JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 74 OP 74 DO 10.1016/rapm-00115550-200609002-00143 VO 31 IS Suppl 2 A1 Erdogdu P. Ekmekci A1 A. A. Yilmaz A1 E. Ozgencil A1 M. Hasdogan A1 O. Akan A1 F. Okten YR 2006 UL http://rapm.bmj.com/content/31/Suppl_2/74.1.abstract AB