Intra-articular clonidine for post-operative analgesia following arthroscopic knee surgery: a systematic review and meta-analysis

Seven randomized controlled trials were included in this meta-analysis to investigate the efficacy of clonidine for postoperative pain management following knee arthroscopy. Included trials compared clonidine to placebo in the immediate postoperative period. Pooled estimates revealed significantly lower pain in those who received clonidine at 1, 2, and 4 hours after surgery. Effects remained constant upon sensitivity analyses. Pain at 6, 12, and 24 hours after surgery was either not significantly different compared to placebo, or subject to change upon sensitivity analysis. Clonidine thus appears effective for managing immediate pain, but not sufficient to manage pain for the duration of the postoperative period following arthroscopic knee surgery.