Injection Site in Ultrasound-Guided Interscalene Block for Shoulder Arthroscopy

Overview

Ultrasound-guided interscalene block is commonly used for postoperative analgesia in patients undergoing shoulder arthroscopy. The location of local anesthetic injection may influence both block efficacy and the incidence of block-related complications. This randomized, double-blind clinical trial compares two different injection sites around the C5-C7 nerve roots using the same local anesthetic dose and volume. The study will assess block success, postoperative analgesia, opioid consumption, diaphragmatic function, and procedure-related complications.

Patients scheduled for elective shoulder arthroscopy under general anesthesia will be randomly assigned to one of two ultrasound-guided interscalene block techniques. In one group, the local anesthetic will be injected between the C5-C7 nerve roots and the anterior scalene muscle. In the other group, the injection will be performed between the C5-C7 nerve roots and the middle scalene muscle. The same local anesthetic solution, volume, and concentration will be used in both groups. Block success, postoperative pain control, opioid consumption, diaphragmatic movement assessed by ultrasonography, and block-related complications including vascular puncture, Horner syndrome, hoarseness, dyspnea, nausea, vomiting, and prolonged motor block will be recorded and compared between the groups.

Conditions