Tehran University of Medical Sciences Journal of Orthopedic and Spine Trauma 2538-2330 12 3 2026 08 26 163 6 Archana Parakar Senior Consultant, M.D Anesthesia, Department of Anesthesia, VIROC Super Specialty Hospital, Vadodara, India Rajiv Paradkar Senior Consultant, M.S Orthopedics, Joint Replacement Unit, Department of Orthopedics, VIROC Super Specialty Hospital, Vadodara, India Vrajesh Shah Senior Consultant, M.S Orthopedics, Joint Replacement Unit, Department of Orthopedics, VIROC Super Specialty Hospital, Vadodara, India Tanmay Jaysingani Consultant, M.S Orthopedics, Joint Replacement Unit, Department of Orthopedics, VIROC Super Specialty Hospital, Vadodara, India Ajinkiya Naik Fellowship in Joint Replacement Unit, M.S Orthopedics, Department of Orthopedics, VIROC Super Specialty Hospital, Vadodara, India Nandlal Bharwani Fellowship in Joint Replacement Unit, M.S Orthopedics, Department of Orthopedics, VIROC Super Specialty Hospital, Vadodara, India 2025 11 17 2026 06 20 Background:Total knee arthroplasty (TKA) is now routinely performed for end-stage knee osteoarthritis (OA), helping improve patient’s quality of life (QoL) and reducing the global economic burden. For effective pain management, peripheral nerve blocks and periarticular local injections are commonly used. The aim of this study was to compare the effectiveness of periarticular injection (PAI) of local anesthetic and ultrasound-guided adductor canal block (ACB) in post-TKA patients. Methods: This prospective study included 60 patients with knee OA undergoing TKA, who were divided into two groups of 30 patients each: ACB group (20 ml of 0.25% ropivacaine) and PAI group (20 ml of 0.5% ropivacaine solution diluted in 20 ml of normal saline with one ampoule of cefuroxime and 4 mg of dexamethasone). The outcomes compared were Visual Analog Scale (VAS) scores on postoperative days (POD) 0, 1, and 2 at rest and during rehabilitation; knee range of motion (ROM); length of hospital stay; and opioid dosage required. Results: VAS scores at rest for both groups were similar at all time intervals. However, during mobilization, a significant difference was observed in VAS scores on POD 1 (1.90 ± 0.88 vs. 2.83 ± 0.70; P = 0.001) and POD 2 (0.70 ± 0.60 vs. 1.47 ± 0.51; P = 0.001). Knee ROM showed a significant difference on POD 0 (84.83 ± 5.80 vs. 81.50 ± 5.28; P = 0.023), with no significant differences on POD 1 and 2. The opioid dose required was significantly lower in the ACB group (1.17 ± 0.65 vs. 3.07 ± 0.87; P < 0.001). Moreover, hospital stay was significantly shorter in the ACB group compared to PAI group (2.53 ± 0.63 vs. 3.07 ± 0.87; P = 0.009). Conclusion: The ultrasound-guided ACB group demonstrated better pain control, improved early knee ROM, reduced opioid consumption, and a shorter duration of hospital stay compared to the PAI group. https://jost.tums.ac.ir/index.php/jost/article/view/736 https://jost.tums.ac.ir/index.php/jost/article/download/736/483