Addition of Adductor Canal Block to Local Infiltration Analgesia Does Not Reduce Postoperative Opioid Use Following Anterior Cruciate Ligament Surgery.

Abstract

Purpose: This propensity-matched cohort study aimed to determine if adding adductor canal block (ACB) to local infiltration analgesia (LIA) reduces immediate postoperative opioid use in anterior cruciate ligament (ACL) reconstruction and assess variations based on graft type.

Methods: This retrospective study analyzed ACL reconstructions performed from 2019 to 2021. Patients were included if they received either LIA alone or a combination of LIA and ACB. Patients were propensity-matched based on demographic and surgical factors, and perioperative opioid consumption was assessed. Subgroup analysis was conducted based on autograft type (hamstring, quadriceps tendon, and bone-patellar tendon-bone).

Results: No significant differences were observed in intraoperative, postanesthesia care unit, or total perioperative opioid consumption between the ACB + LIA group (27.76 ± 14.01 mg) and the LIA-only group (28.58 ± 12.56 mg). This finding was consistent across all autograft types. However, in the hamstring autograft subgroup, the addition of ACB led to a statistically significant reduction in postanesthesia care unit opioid consumption (30.99 vs 26.45 mg, P = .039), although this difference was not deemed clinically significant. Additionally, the ACB + LIA group experienced a significantly longer mean time to discharge (495 ± 113 minutes) compared to the LIA-only group (463 ± 116 minutes; P = .017).

Conclusions: Our findings suggest that adding ACB to LIA does not provide additional opioid-sparing benefits in ACL reconstruction, except in patients with hamstring grafts, where the difference observed may not be of clinical significance. The increased discharge time with ACB highlights the need to balance benefits with operational efficiency.

Level of evidence: Level III, retrospective matched comparative case series.