Ninety adults undergoing elective unilateral total hip arthroplasty were randomized into three equal groups based on the anatomical region of continuous fascia iliaca compartment block catheter placement: medial (Group I), middle (Group II), or lateral (Group III). All patients received standardized general anesthesia and postoperative continuous ropivacaine infusion via the fascia iliaca catheter for 48 hours. The outcomes were postoperative pain during activity measured by the Numerical Rating Scale, sensory block characteristics, effective analgesic pump compression counts, cumulative ropivacaine dose, rescue analgesia use, time to first ambulation, and adverse events. Overall, the results of the study revealed that catheter placement in the medial and middle regions resulted in significantly lower pain scores during activity from 12 to 48 hours postoperatively and reduced analgesic pump use compared with lateral placement, with no increase in adverse events. These findings suggest that medial or middle fascia iliaca catheter positioning provides superior postoperative analgesia following total hip arthroplasty.