Evaluation of intra-articular injection of bupivacaine with morphine or methylprednisolone or alone on pain after knee arthroscopy

Knee arthroscopy is used to diagnose and treat intra-articular lesions. Controlling acute pain after arthroscopy requires the use of a method with the least side effects and the most efficiency. The aim of this study was to compare the sedative effect after intra-articular injection of bupivacaine combination with morphine or methylprednisolone or alone in knee arthroscopy.

In this study clinical-randomized three-blind trial, 99 volunteer patients with knee arthroscopy were randomly divided into three groups: 1. Bupivacaine (0.5%), 2. Morphine (5 mg)+ bupivacaine (0.5%) and 3. Methylprednisolone (40 mg) + bupivacaine (0.5%). At the end of the operation, drugs were injected intra-articular and the amount of postoperative pain was evaluated and recorded based on visual analog scales 6, 12, 18, and 24 hours after injection. Also, receiving the injected analgesic within 24 hours, was recorded. Data were analyzed using SPSS software and repeated measures analysis of variance.

In all three groups, the pain intensity decreased significantly over time. The pain intensity of the methylprednisolone + bupivacaine and morphine+bupivacaine group was the similar, at different postoperative periods, but the pain intensity of these groups was significantly lower than the control. Also, consumption of the analgesics was significantly reduced in methylprednisolone+bupivacaine group compared to the two other groups.

The results of this study showed that intra-articular injection of methylprednisolone + bupivacaine and morphine+bupivacaine was more effective than bupivacaine alone in reducing pain and the need for injectable analgesia.