The analgesic effect of fascia iliaca compartment block combined with superior cluneal nerve block after total hip arthroplasty: a prospective, triple-blind, randomized controlled trial

Postoperative analgesia for total hip arthroplasty (THA) constitutes a pivotal component of perioperative management. The fascia iliaca compartment block (FICB) is a widely utilized technique in clinical practice. However, FICB does not cover the sensory areas of the upper buttock. The superior cluneal nerve block (SCNB) is increasingly recognized as a supplementary analgesic method for hip surgery nerve blocks. The present study aims to investigate the analgesic effect of the combination of FICB and SCNB after total hip arthroplasty. This study was conducted as a triple-blind randomized controlled trial, and a total of 82 patients scheduled for elective total hip arthroplasty under general anesthesia were enrolled. Participants were randomly allocated in a 1:1 ratio to receive either preoperative FICB or FICB combined with SCNB. The primary outcome was total morphine equivalent consumption during the first 48 postoperative hours. Secondary outcomes included total morphine equivalent consumption during the first 24 postoperative hours, resting and movement numerical rating scale (NRS) scores at various postoperative time points, 24- and 48-hour Quality of Recovery-15 (QoR-15) scores, time to first patient-controlled analgesia (PCA) request, and incidence of adverse events, among others. Patients receiving FICB + SCNB demonstrated a reduction in total 48-hour postoperative morphine equivalent consumption compared to those receiving FICB alone (mean ± SD: 62.0 ± 5.6 mg vs. 67.1 ± 5.3 mg; P < 0.001). Additionally, the FICB + SCNB group exhibited lower resting and movement numerical rating scale (NRS) scores at 2, 6 h postoperatively, prolonged time to first patient-controlled analgesia (PCA) request, and higher 24- and 48-hour Quality of Recovery-15 (QoR-15) scores. Compared with FICB alone, the combined use of FICB and SCNB reduced postoperative opioid consumption in THA patients; however, this reduction did not reach the minimum clinically important difference (MCID). ChiCTR2400087285. Registered 24 July 2024.