RESUMEN
OBJECTIVE: This study compares the efficacy in post-operative pain control of the intraarticular catheter compared to the epidural catheter after primary total knee arthroplasty. MATERIAL AND METHOD: Randomised clinical trial consisting of two groups of patients. A control group with intradural anaesthesia and an intraoperative epidural catheter (ropivacaine) and an intervention group using the same anaesthetic technique and an intraarticular catheter with an elastomeric pump (ropivacaine+dexketoprofen). Data such as demographic, anaesthetic and surgical variables, pain intensity according to Verbal Rating Scale, opioid use and complications, joint balance, onset of walking and hospital stay were recorded. RESULTS: A lower incidence and severity on Verbal Rating Scale and a better control of postoperative pain (p<.0014) were observed in the intervention group. Joint balance also presented significant results in flexion and 74% of these patients started walking before the first 36h and the control group had not yet done so. Regarding patient satisfaction, 54.1% of the patients were "very satisfied" with the use of the catheter (p>.001). Finally, the hospital stay decreased significantly, with 33.3% of intervention group patients discharged within the first 48h compared to none of the control group. DISCUSSION AND CONCLUSIONS: The use of the intraarticular catheter as postoperative analgesia is a useful and safe alternative. It reduces the possibility of side effects. It helps in early improvement of joint balance, onset of walking and control of pain. All of which increase patient satisfaction and result in a shorter period of hospitalisation.