Comparative evaluation of Para-sartorial compartments block versus adductor canal block for post-operative analgesia in total knee replacement surgeries: A prospective randomized study

Abstract

Background: Effective post-operative analgesia after total knee replacement (TKR) is vital for early mobilization and recovery. Adductor canal block (ACB) is widely used due to its motor-sparing effect, though its analgesic coverage may be limited. The para-sartorial compartments block (PASCB) is a newer ultrasound-guided technique designed to provide broader anterior knee analgesia while preserving motor function. Aims and Objectives: The aim of the study was to compare the efficacy of PASCB and ACB for post-operative analgesia in unilateral TKR. Materials and Methods: This prospective randomized study included 40 patients undergoing unilateral primary TKR under spinal anesthesia. Patients were allocated into two groups (n=20 each). Group ACB received ultrasound-guided ACB, while Group PASCB received ultrasound-guided PASCB at surgery completion. The primary outcome was 24-h tramadol consumption. Secondary outcomes included pain scores, numerical rating scale, time to first rescue analgesia, Bromage motor block score, ambulation time, and adverse events. Results: Mean tramadol use was significantly lower in Group PASCB compared to Group ACB (74.5±24.3 mg vs. 108.0±31.6 mg; P=0.001). Pain scores at rest and movement were lower in PASCB at 6, 12, and 24 h. Time to first rescue analgesia was longer in PASCB (9.4±2.3 h vs. 6.7±1.9 h; P<0.001). Motor block and ambulation were similar. Post-operative nausea and vomiting were less frequent in PASCB. Conclusion: PASCB provided superior analgesia, reduced opioid requirement, and prolonged analgesic duration compared to ACB, while maintaining motor function in TKR patients.