Sixty patients undergoing elective posterior-approach total hip arthroplasty (THA) were randomized to receive either an ultrasound-guided supra-inguinal fascia iliaca block (SFIB) (n=30) or a pericapsular nerve group (PENG) block (n=30). The primary outcome was 24-hour cumulative intravenous fentanyl consumption. Secondary outcomes included perioperative fentanyl use, pain scores at rest and with movement across hip regions, cutaneous sensory loss, quadriceps strength, functional measures (TUG, QMS), and adverse events. Outcomes were assessed from PACU through 48 hours postoperatively. Overall, the results revealed no significant difference in opioid consumption or pain scores between groups at all time points, although PENG demonstrated shorter sensory block duration and slightly better quadriceps strength at 12 hours. These findings suggest that when combined with multimodal analgesia, PENG does not provide superior analgesic benefit compared with SFIB after posterior-approach THA.