Bupivacaine Liposome Plus Bupivacaine or Ropivacaine for Pericapsular Nerve Group Block in Hip Arthroplasty (PENG)

The goal of this clinical trial is to study the analgesic effect of liposomal bupivacaine plus bupivacaine for Pericapsular Nerve Group (PENG) block in postoperative pain management following hip replacement surgery. It will also assess the safety of liposomal bupivacaine for this purpose. The main questions it aims to answer are: 1. Is liposomal bupivacaine plus bupivacaine superior to ropivacaine in terms of analgesic efficacy, duration of pain relief, opioid consumption, and patient satisfaction? 2. What medical problems do participants encounter when using liposomal bupivacaine plus bupivacaine for PENG block in postoperative pain management following hip replacement surgery? Researchers will compare liposomal bupivacaine plus bupivacaine to ropivacaine (a routinely used regional anesthetic in clinical practice) to determine if liposomal bupivacaine plus bupivacaine is more effective for pain management following hip replacement surgery. Participants will: 1. Receive liposomal bupivacaine plus bupivacaine or ropivacaine as a regional anesthetic for PENG block under ultrasound guidance. 2. Undergo hip replacement surgery under spinal anesthesia. 3. Have pain relief, opioid analgesic consumption, and incidence of complications assessed at multiple time points within 72 hours after surgery.