Deep Subgluteal Block vs PENG Combined With LFCN Block for Analgesia After Hip Arthroplasty

Overview

This randomized, prospective study aims to compare the clinical efficacy of ultrasound-guided Deep Subgluteal Block (DSGB) versus Pericapsular Nerve Group (PENG) block combined with Lateral Femoral Cutaneous Nerve (LFCN) block for postoperative analgesia management in patients undergoing hip arthroplasty. A total of 60 patients scheduled for hip arthroplasty under general anesthesia will be randomly allocated into two equal groups of 30: Group DSG and Group PENG+LFCN. Total local anesthetic volume (30 mL) and active drug dose (75 mg bupivacaine) will be standardized across both groups to ensure rigorous blinding and high methodological quality. The primary outcome of the study is to compare total postoperative opioid (fentanyl) consumption within the first 24 hours. Secondary outcomes include postoperative pain scores evaluated via the Numerical Rating Scale (NRS) at rest and during movement, the presence and degree of quadriceps motor block, and opioid-related adverse effects (e.g., nausea, vomiting, pruritus).

This randomized, prospective, double-blind study is designed to evaluate and compare the postoperative analgesic efficacy of two different ultrasound-guided regional anesthesia techniques in patients undergoing elective hip arthroplasty under general anesthesia. Following institutional ethical approval and written informed consent, a total of 60 patients will be randomly allocated into two equal groups (n=30 per group): Group DSG (Deep Subgluteal Block) and Group PENG+LFCN (Pericapsular Nerve Group block combined with Lateral Femoral Cutaneous Nerve block). To optimize methodological quality, minimize bias, and maintain a strict double-blind design, both total local anesthetic volume (30 mL) and total active drug dose (75 mg bupivacaine) are perfectly standardized between the groups. All regional blocks will be performed by an experienced anesthesiologist using a high-frequency ultrasound transducer under sterile conditions after surgery is completed but before patient emergence/extubation. In Group DSG (n=30), patients will receive a total of 30 mL of 0.25% bupivacaine (15 mL administered beneath the gluteus minimus muscle and 15 mL beneath the gluteus medius muscle). No saline will be added to this group. In Group PENG+LFCN (n=30), patients will receive a total injection volume of 30 mL divided into two separate targets. First, the PENG block will be performed with 20 mL of 0.25% bupivacaine. Second, the LFCN block will be performed using a 10 mL volume consisting of 5 mL of 0.25% bupivacaine diluted with 5 mL of normal saline (0.9% NaCl), resulting in a final local anesthetic concentration of 0.125% bupivacaine at the LFCN site. Following block administration, a standard general anesthesia protocol will be applied. Postoperative patient-controlled analgesia (PCA) with intravenous fentanyl (10 mcg/mL solution, 10 mcg bolus, 10-minute lockout time, no basal infusion) will be initiated in the post-anesthesia care unit (PACU). Multi-modal analgesia will be supplemented with scheduled oral/IV ibuprofen (400 mg every 8 hours) and tramadol administered 30 minutes before the end of surgery. Postoperative pain assessments will be performed by a blinded independent investigator at 0 (PACU), 2, 4, 8, 16, and 24 hours using the Numerical Rating Scale (NRS) both at rest and during movement. In case of severe pain (NRS \>= 4), intravenous meperidine (0.5 mg/kg) will be administered as rescue analgesia. Cumulative opioid consumption, quadriceps motor strength (evaluated via the Oxford Muscle Strength Scale), and opioid-related adverse effects (such as postoperative nausea, vomiting, or pruritus) will be comprehensively monitored and recorded for the first 24 hours.