Satisfactory perioperative management for hip arthroscopy with small local pericapsular nerve group block: a single-center, double-blind, randomized controlled trial

BACKGROUND: Current analgesic options for hip arthroscopy include fascia iliaca block and peripheral nerve block of the hip. Although the latter provides effective analgesia with reduced motor impairment compared with the fascia iliaca approach, motor blockade still occurs in ≥ 25% of patients. This study aimed to investigate whether administering low-volume local anesthetic for peripheral nerve blockade in the hip reduces the incidence of postoperative quadriceps weakness while maintaining adequate pain control. METHODS: A total of 90 patients who underwent hip arthroscopy were randomly assigned to one of three groups. The first group was administered a fascia iliaca compartment block (FICB), the second group was administered a pericapsular nerve group (PENG) block with 20 ml of local anesthetic, and the third group was administered a PENG block with 10 ml of local anesthetic. The primary outcome measure was postoperative quadriceps muscle strength, whereas the secondary outcome measures were the postoperative 2-h Numeric Rating Scale (NRS) score, intraoperative changes in blood pressure and heart rate, NRS score at one day after surgery, intraoperative and postoperative opioid consumption, postoperative complications, length of hospital stay, patient satisfaction, pain experience, and quality of recovery. RESULTS: No evidence of a difference were observed in the basic statistical parameters among the three patient groups. Moreover, no significant discrepancies were identified in the NRS scores at the 2-h or 1-day post-operative intervals. However, a marked difference in quadriceps muscle strength was evident among the three groups at the 2-h post-operative mark (PENG 10 ml = 3.43 ± 0.45, PENG 20 ml = 2.43 ± 1.81, FICB = 0.57 ± 0.82; p < 0.001). There was a difference in the quality of postoperative recovery (PENG 10 ml = 125.57 ± 4.70, PENG 20 ml = 123.53 ± 5.45, FICB = 120.80 ± 3.34; p < 0.01), with no significant difference in any other outcome. CONCLUSIONS: In patients undergoing hip arthroscopy, preoperative FICB, PENG (10 mL), and PENG (20 mL) blocks resulted in comparable intraoperative stress responses and provided comparable, satisfactory postoperative analgesia.However, patients who received low-volume PENG blocks demonstrated superior postoperative preservation of quadriceps muscle strength and a statistically significant improvement in the quality of recovery. Notably, the magnitude of this improvement in recovery quality did not exceed the minimal clinically important difference. TRIAL REGISTRATION NUMBER: ChiCTR2400091099. Date: October 21, 2024; retrospectively registered. URL: https://www.chictr.org.cn/ .