Comparison of the pericapsular nerve group block with the intra-articular and quadratus lumborum blocks in primary total hip arthroplasty: a randomized controlled trial.

Background: The pericapsular nerve group (PENG) block, quadratus lumborum block (QLB), and intra-articular (IA) local anesthetic injection have been shown to provide effective analgesia in total hip arthroplasty (THA). This randomized study aimed to compare the analgesic efficacy, motor protection, and quality of recovery associated with the PENG block, QLB, and IA injection.

Methods: Eighty-nine patients who underwent a unilateral primary THA under spinal anesthesia were randomly assigned to the PENG (n=30), QLB (n=30), or IA (n=29) group. The primary outcome was the numerical rating scale (NRS) score over the first 48 h postoperatively. The secondary outcomes were postoperative opioid consumption, quadriceps and adductor muscle strength, and quality of recovery (QoR-40).

Results: The dynamic (with movement) NRS scores at 3 and 6 h postoperatively were significantly lower in the PENG and QLB groups compared to the IA group (P = 0.002 and P < 0.001, respectively). The time to first opioid analgesia requirement was longer in the PENG and QLB groups than in the IA group (P = 0.009 and P = 0.016, respectively). A provided better preservation was found in the the PENG group than in the QLB group in terms of quadriceps muscle strength at 3 h postoperatively (P = 0.007) and time to mobilization (P = 0.003). No significant differences in the QoR-40 scores were seen.

Conclusions: The PENG and QLB groups showed similar analgesic effects and both showed more effective analgesia 6 h postoperatively than the IA group. All the groups showed similar postoperative quality of recovery.