Pericapsular Nerve Group (PENG) Block for Hip Arthroscopy: a Randomized, Double-Blinded, Placebo-Controlled Trial

Introduction Arthroscopic hip surgery is associated with significant postoperative pain. Femoral nerve blocks have been shown to improve postoperative analgesia at the expense of quadriceps weakness. The pericapsular nerve group (PENG) block could be an alternative that may improve postoperative analgesia while preserving quadriceps strength. Our hypothesis was that a PENG block would provide superior postoperative analgesia compared with a sham block following arthroscopic hip surgery. Methods Subjects presenting for arthroscopic hip surgery were randomized in a 1:1 ratio to either an ultrasound-guided unilateral, single-injection PENG block (PENG group) with 20 mL of 0.5% ropivacaine or a sham injection with 5 mL of 0.9% normal saline (Sham group) prior to receiving general anesthesia. The primary outcome of this study was worst pain score within 30 min of emergence from anesthesia. Secondary outcomes included opioid consumption, patient satisfaction with analgesia, opioid-related adverse events, and persistent opioid use at 1 week. Results Sixty-eight subjects, 34 from the PENG group and 34 from the Sham group, completed the study per protocol. Analysis of the primary outcome demonstrated a mean difference in pain scores of −0.79 (95% CI −1.96 to 0.37; p=0.17) between the PENG and Sham groups immediately following surgery. No secondary outcomes showed statistically significant differences between groups. Discussion This study demonstrates that a preoperative PENG block does not improve analgesia following arthroscopic hip surgery. Trial reigstration number NCT04508504