Objective: To compare the effects of epidural analgesia,intravenous analgesia and intra-articular analgesia on reducing postoperative pain and modulating the inflammatory cytokine response to tend to balance after total knee replacement. Methods: A total of sixty patients were randomly divided into three groups( n = 20). Epidural group: loading dose( morphine) was administrated by epidural injection,and patients controlled epidural analgesia after operation; intravenous group: loading dose( tramadol) was ad...