165 patients scheduled for total hip arthroplasty were randomized to one of three groups for postoperative analgesia: periarticular infiltration with ropivacaine (PAI-R), periarticular infiltration with liposomal bupivacaine (PAI-L), or peripheral nerve block (PNB) via a continuous lumbar plexus block. The primary outcome was maximum pain severity experienced during the morning of postoperative day 1. Results demonstrated statistically significantly lower pain among patients administered the continuous lumbar plexus block compared to periarticular infiltration analgesia with ropivacaine; the differences between the PAI-L group and the PAI-R group, and the PAI-L group and the PNB group, were not statistically significant.