Postoperative Pain Control After ACL Reconstruction With Semitendinosus Tendon Graft: A Randomized Controlled Trial Comparing Adductor Canal Block to Local Infiltration Analgesia.

Background: Both adductor canal block (ACB) and local infiltration (LI) are effective for postoperative pain management after arthroscopic-assisted anterior cruciate ligament (ACL) reconstruction (ACLR). While LI is a more straightforward procedure, its effectiveness remains debated. Purpose: To evaluate morphine consumption within 48 hours after ACLR with a semitendinosus tendon graft, comparing ACB and LI; secondary objectives: to evaluate pain levels, patient satisfaction, quadriceps strength, range of knee motion, and complications. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: Patients undergoing primary ACLR with a semitendinosus tendon graft were randomized to receive either ACB (0.25% bupivacaine; 20 mL) or LI at the surgical wound, graft harvest area, and intra-articular injection. The LI group received morphine (3 mg), ketorolac (30 mg), and tranexamic acid (1 g). Morphine consumption within 48 hours was monitored using an intravenous patient-controlled analgesia device. Results: A total of 48 patients were analyzed (n = 24 in each group); baseline characteristics were similar between groups. The LI group consumed significantly less morphine than the ACB group at 6 hours (median [interquartile range, IQR], 3 mg [0-4.8 mg] for the LI group vs 5.5 mg [2-9] for the ACB group; Conclusion: Morphine consumption at 48 hours postoperatively was comparable between the LI and ACB groups, and no significant group differences were found in postoperative pain, quadriceps strength, or patient satisfaction. Registration: TCTR20190320003 (Thai Clinical Trial Registry).