Fifty adults with knee osteoarthritis undergoing unilateral primary total knee arthroplasty (TKA) were randomized in a double-blind, placebo-controlled trial to receive either adductor canal block and genicular nerve block (Group 1) or adductor canal block and a placebo genicular block (Group 2). All patients received standardized spinal anesthesia and multimodal analgesia. The primary outcome was cumulative morphine consumption during the first 24 postoperative hours. Secondary outcomes included pain scores at rest and with movement, time to first rescue analgesia, patient satisfaction, and adverse effects. Overall, the results revealed that combining genicular nerve block with adductor canal block resulted in markedly lower opioid consumption, lower pain scores at multiple postoperative time points, delayed need for rescue analgesia, and higher patient satisfaction, without increasing adverse events. These findings indicate that genicular nerve block is an effective motor-sparing adjunct to adductor canal block for pain control after total knee arthroplasty.