INTRAARTICULAR ANALGESIA FOR ARTHROSCOPIC MENISCECTOMY

Intra-articular morphine has been shown to provide prolonged analgesia after arthroscopic knee surgery; the addition of local anaesthetic ag ents has been reported to improve this analgesic effect. Pethidine pos sesses local anaesthetic properties, and therefore this study was desi gned to evaluate its analgesic efficacy after arthroscopic meniscectom y. Sixty patients were allocated randomly to receive intra-articular i njections of pethidine 50 mg, morphine 5 mg or saline after elective a rthroscopic meniscectomy. Postoperative pain was assessed using an int erval visual analogue scale and measuring analgesic requirements. Both treatment groups had significantly lower pain scores compared with th e control group. Patients in the pethidine group had lower pain scores than those in the morphine group at 0.5, 1 and 2 h, but significantly higher scores at 12 and 24 h. These observations suggest that the loc al anaesthetic effect of pethidine may be responsible for the improved early analgesia, but its duration of action appears to be less than t hat of morphine.