Response to Wang et al. "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".

We appreciate the opportunity to respond to the thoughtful comments regarding our randomized controlled trial that compared the continuous pericapsular nerve group block and the continuous supra-inguinal fascia iliaca compartment block techniques for postoperative pain management following total hip arthroplasty. Both groups in our study were demographically comparable. All participants underwent elective, unilateral, primary total hip arthroplasty and were classified as American Society of Anesthesiologists physical status I or II. Randomization was performed using a computer-generated sequence with allocation concealment, minimizing the risk of selection bias. In terms of analgesic protocol, every patient received scheduled intravenous administration of the non-steroidal anti-inflammatory drug ibuprofen and patient-controlled analgesia with tramadol. Intravenous paracetamol was administered only as a rescue medication when the visual analog scale pain score exceeded four. Although several guidelines, such as the enhanced recovery after surgery and the procedure-specific postoperative pain management guidelines published by the European Society of Regional Anaesthesia, recommend routine scheduled use of paracetamol along with nonsteroidal anti-inflammatory drugs, both groups in our study followed the same analgesic regimen. This uniformity supports the internal validity of our comparative results. We observed that the group receiving the pericapsular nerve group block showed a continuous decline in pain scores, while the fascia iliaca compartment block group experienced increasing pain after six hours. Although the difference in opioid use was slightly below the minimal clinically important difference, it was accompanied by lower pain scores and less need for rescue medication. We acknowledge the absence of patient-reported outcomes as a limitation and encourage their inclusion in future research.