The effects of intra-articular injection of marcaine on post aspiration pain of knees with osteoarthritis

Abstract Osteoarthritis is the most common joint disease in a large number of old people that can cause pain and disability. Intra-articular injection is one of the recommended procedures to reduce this pain. In this issue some disagreements about analgesic effect of marcaine's (a trade name for bupivacaine) intra-articular injection for post operation pain due to knee surgeries has been seen. In this double-blind randomized clinical trial study, 22 patients with osteoarthritis were involved. Those have been electively referred to orthopedic and pain clinic of Zahedanskhatam-alanbia hospital between 2010 and 2011. One of the patient's knees randomly considered as case knee and another knee as control. Before any intervention each knee's pain was measured from 1 to 10 by Numeric Rating Scale (NRS) and has been recorded. Then 4ml of 0.5% marcaine injected in case knee and 4ml saline injected in control. After 5 minutes, without removing the needle from the joint, synovial fluid aspirated, and aspiration pain measured with the same NRS scale. Afterward 40mg methylprednisolone was injected in both knees. Then pain separately measured in 1, 6, and 24 hours and finally one week after aspiration. Data were recorded and processed by SPSS software, version 18. Moreover, the paired test and Anova test were used for data analysis. In this study 22 patient, 12 female (54.5%) and 10 men (45.5%) were attended. The age average was 55.09 years and they were between 38 and 72 years old. Comparisons showed significant differences between case and control group in pain (P<0.001). Intra articular injections of marcaine can significantly relieves the pain after knee joint aspiration in patients with osteoarthritis, and it can be useful in this category.