Seventy-eight patients undergoing total knee arthroplasty were randomized to receive either a single-injection adductor canal block with 0.5% ropivacaine (n=39) or a placebo with saline (n=39). The primary outcome was pain score on the numerical rating scale (NRS) at rest and during movement at 2, 6, 12, and 24 hours postoperatively. Secondary outcomes included morphine-equivalent consumption, nausea/vomiting scores, quadriceps strength, and patient satisfaction. Outcomes were assessed up to 48 hours post-block. Overall, the study revealed that the SACB group experienced significantly lower pain scores at 6 and 12 hours but not at 24 hours. Patient satisfaction and quadriceps strength were higher in the SACB group. These findings suggest SACB improves early postoperative pain management and satisfaction without compromising motor function.