A RANDOMISED BLINDED CLINICAL TRIAL ASSESSING EFFICACY OF PERI-ARTICULAR INJECTION USING MULTIMODAL ANALGESIA IN TOTAL KNEE REPLACEMENT

Introduction: Post-operative analgesia using parenteral opioids or epidural analgesia can be associated with troublesome side effects. Good peri-operative analgesia facilitates rehabilitation, improves patient satisfaction and may reduce hospital stay. Locally administered pre-emptive analgesia is effective, reduces central hyper-sensitisation and avoids systemic drug related side-effects and may be of benefit in minimally invasive joint replacement. Materials and methods: 64 patients undergoing total knee replacement were randomised to receive a peri-articular intra-operative injection containing ropiva-caine, ketorolac, epimorphine and epinephrine. The anaesthetic analgesic regime was standardised. All patients received patient controlled analgesia (PCA) for 24 hours post surgery, followed by standard analgesia. VAS pain scores during activity and at rest and patient satisfaction scores were recorded pre and post operatively and at 6 week follow up. PCA consumption and overall analgesic requirement were measured. Results: PCA use over 24 hours post surgery was significantly less in patients receiving the injection (P=0.013). Patient satisfaction at 4 hrs post operation was greater (P=0.003). VAS for pain during activity at 4 hrs and 24 hours were significantly less (P=0.001) in the injected group. The average ROM at 6 weeks was no different. Overall hospital stay and the incidence of wound complications was not different between the 2 groups. Discussion: Peri-articular intra-operative multimodal analgesia significantly reduces post-operative analgesia requirement. Patient satisfaction is greater in the injection group. No cardio and central nervous system toxicity was observed.