Intra-articular Morphine and Clonidine Injection after HipArthroscopy:A Randomized,Triple-Blind ControlledTrial

Hip arthroscopy is an increasingly common outpatient procedure for which postoperative pain control remains a vital component of patient care and surgical outcome.The objective of this study was to determine the effect of intra-articular morphine and clonidine injection as compared with placebo on postoperative opioid requirement after hip arthroscopy. Seventy patients undergoing primary hip arthroscopy were randomized to receive an 11mL intra-articular injection of 10mg morphine + 100mcg clonidine (study) or normal saline (control) at the conclusion of arthroscopy.The primary outcome was opioid consumption during recovery in the post-anesthesia care unit (PACU). Mean PACU opioid consumption in oral morphine equivalents (mEq) in the study group was 37.0 [95% CI: 28.8-45.3] compared to 40.1 [95% CI: 31.8-48.4] in the control group (P=0.29).With the numbers available, intraoperative intra-articular morphine and clonidine injection showed no statistically significant difference in PACU postoperative opioid consumption compared to normal saline control after hip arthroscopy.