Effects of intraarticular morphine on analgesic requirements after anterior cruciate ligament repair

Background and Objectives. Intraarticular morphine has been shown to provide postoperative pain relief after knee arthroscopy. The analgesia results from local action within the knee joint. This study was conducted to assess the efficacy of intraarticular morphine as a treatment for postoperative pain after anterior cruciate ligament repair. Methods. A randomized double blind-study was conducted in patients undergoing elective anterior cruciate ligament repair. Patients in the study group (n = 10) received intraarticularly 5 mg of morphine in a 25 ml dilution. Those in the control group (n = 10) received 25 ml of saline by the same route. Intravenous morphine with patient-controlled analgesia was used in the postoperative period in both the groups. Visual analog scores were recorded at 1,2, 4, 8, and 24 hours after the operation. The amount of morphine used over the 24-hour postoperative period was documented. Results. The total consumption of morphine over the 24-hour period was significantly lower (p < 0.01) in the study group compared to the control group. The postoperative pain scores were lower in the study group throughout the study period, but this did not reach statistical significance. Conclusions. Intraarticular morphine reduces analgesic requirements after anterior cruciate ligament repair and is an effective method of providing postoperative analgesia.