Comparative analysis of continuous pericapsular nerve group block and supra-inguinal fascia iliaca compartment block for postoperative analgesia in total hip arthroplasty: a randomized controlled trial

Abstract

Background: Effective postoperative pain management is essential for recovery after total hip arthroplasty. While opioids are commonly used, their adverse effects necessitate alternative strategies. Peripheral nerve blocks are increasingly utilized, including the pericapsular nerve group block and the supra-inguinal fascia iliaca compartment block. However, comparative data on their efficacy remain limited. This randomized controlled trial evaluated the analgesic effectiveness of these two techniques. The primary outcome was postoperative pain scores at rest and with movement. Secondary outcomes included opioid consumption, the need for rescue analgesia, and hemodynamic stability.

Methods: Sixty patients undergoing total hip arthroplasty under general anesthesia were randomly assigned to receive either a pericapsular nerve group block or a supra-inguinal fascia iliaca compartment block. Standardized ultrasound-guided techniques were used with equal volumes of local anesthetic. Pain scores were assessed postoperatively using the Visual Analog Scale. Opioid consumption and rescue analgesia use were recorded for twenty-four hours.

Results: At 12 and 24 h postoperatively, median VAS scores at rest and during movement were significantly lower in the PENG group (≤ 2.0) compared to the SIFICB group (> 4.0) (P < 0.001). Opioid consumption in the first 24 h was significantly lower in the PENG group (11.1 ± 1.5 mg morphine equivalents) than in the SIFICB group (18.4 ± 2.5 mg; P < 0.001). Hemodynamic parameters were stable, with no significant complications.

Conclusions: The pericapsular nerve group block provided superior analgesia and reduced opioid consumption compared to the supra-inguinal fascia iliaca compartment block. It should be considered a practical component of multimodal pain management for total hip arthroplasty.

Irb number: Ethics Committee of Tekirdağ Namık Kemal University (2023.06.01.06).

Clinical trial registration number: https://clinicaltrials.gov (NCT06806865).

Keywords: Acute pain; Pain management; Postoperative pain; Regional anesthesia; Total hip arthroplasty; Ultrasonography.

Fig. 1

Consolidated Standards of Reporting Trials (CONSORT) flow chart illustrating patient enrollment, allocation, follow-up, and analysis in the study. PCA: patient-controlled analgesia; PENG: pericapsular nerve group; SIFICB: supra-inguinal fascia iliaca compartment block

Fig. 2

A basic illustration of the pericapsular nerve group (PENG) block: Key anatomical structures include the iliacus and psoas muscles, psoas tendon, femoral artery, femoral vein, and femoral nerve. The image also depicts local anesthetic distribution in the pericapsular region for analgesia. FA: femoral artery; FV: femoral vein; FN: femoral nerve; LA: local anesthetic

Fig. 3

A basic illustration of the supra-inguinal fascia iliaca compartment block (SIFICB): The image highlights key anatomical structures, including the iliopsoas, sartorius, transversus abdominis, internal oblique muscles, as well as the iliac fascia. Upward triangles indicate the fascia iliaca, where local anesthetic is injected. The spread of LA within the supra-inguinal compartment and the deep circumflex iliac artery as a vascular landmark are also depicted. LA: local anesthetic

Fig. 4

(A) Relative treatment effects (RTE) for heart rate over time, showing comparable patterns between PENG block and SIFICB groups with a minor elevation in the SIFICB group at 4 h, though not clinically significant (interaction effect: P = 0.066). Y-axis indicates RTE values for heart rate; X-axis indicates time (hours) postoperatively. (B) Temporal analysis of mean arterial pressure relative treatment effects, demonstrating hemodynamic stability in both groups throughout the observation period, with no significant between-group differences (P = 0.374). Y-axis indicates RTE values for MAP; X-axis indicates postoperative time in hours. RTE: relative treatment effect; MAP: mean arterial pressure; PENG: pericapsular nerve group; SIFICB: supra-inguinal fascia iliaca compartment block

Fig. 5

(A) Relative treatment effects (RTE) analysis of VAS scores during movement revealing divergent patterns between groups after 6 h, with the PENG block maintaining superior pain control through 24 h (interaction effect: P < 0.001). Y-axis indicates RTE values for VAS scores during movement; X-axis indicates postoperative time in hours. (B) Comparison of relative treatment effects for VAS scores at rest, illustrating sustained analgesic efficacy in the PENG block group versus progressive pain increase in the SIFICB group (interaction effect: P < 0.001). Y-axis indicates RTE values for VAS at rest; X-axis indicates time after surgery. VAS: visual analog scale; RTE: relative treatment effect; PENG: pericapsular nerve group; SIFICB: supra-inguinal fascia iliaca compartment block