Effects of Genicular Nerve Blocks in Combination With an Adductor Canal Block in Patients Undergoing Arthroscopic Knee Surgery: A Randomized Controlled Trial.

BACKGROUND AND OBJECTIVES

Arthroscopic knee surgery is increasingly popular. Optimal postoperative pain management enhances patient satisfaction and minimizes hospitalization. Numerous studies have demonstrated the benefits of adductor canal blocks (ACBs) and genicular nerve blocks (GNBs) in postoperative analgesia. This study aims to evaluate the efficacy of adding GNBs to an ACB in reducing postoperative pain scores compared to an ACB alone. Additionally, it seeks to compare secondary outcomes, including opioid consumption, motor blockade, nausea and vomiting, rash, and itching during the postoperative period.

METHOD

This prospective, randomized, controlled clinical trial included 49 patients undergoing arthroscopic knee surgery. The study group received a GNB with 0.25% bupivacaine (3 mL) at each quadrant of the knee, except for the inferolateral quadrant, in combination with an ACB using 0.25% bupivacaine (20 mL). The control group received an ACB alone. Fentanyl (1-2 mcg/kg IV) was administered as rescue analgesia during the perioperative period. Pain scores (visual analog score (VAS)), cumulative opioid consumption, motor blockade, and incidences of postoperative nausea and vomiting (PONV) and itching were assessed at six, 12, 24, and 48 hours postoperatively.

RESULTS

No statistically significant differences in median pain scores were observed between the groups. However, postoperative opioid consumption was significantly lower in the study group, with median values (interquartile range (IQR)) of 0 (0, 30) at 12, 24, and 48 hours postoperatively compared to the control group (p ≤ 0.001). Additionally, no significant differences were found between groups regarding motor blockade or opioid-related side effects.

CONCLUSION

Adding GNBs to an ACB did not demonstrate superiority in reducing postoperative pain scores. However, it effectively reduced perioperative opioid consumption at 12 to 48 hours postoperatively without increasing adverse effects such as nausea, vomiting, or motor blockade. These findings highlight the potential of GNBs as a valuable component of postoperative pain management strategies for arthroscopic knee surgery.