Hip fracture surgery is commonly associated with moderate to severe postoperative pain, which may delay mobilization and increase the need for opioid analgesics. The deep iliacus plane block is a recently described ultrasound-guided regional anesthesia technique designed to provide analgesia by allowing local anesthetic spread toward the femoral nerve, lateral femoral cutaneous nerve, and articular branches supplying the hip.

This prospective, randomized, double-blind, sham-controlled clinical trial will evaluate the analgesic efficacy of the deep iliacus plane block in adult patients undergoing hip fracture surgery under spinal anesthesia. After surgery, participants will be randomly assigned to receive either an ultrasound-guided deep iliacus plane block with local anesthetic or a sham block with normal saline.

All participants will receive standardized multimodal postoperative analgesia, including patient-controlled analgesia. The primary objective is to determine whether the deep iliacus plane block reduces postoperative opioid consumption during the first 24 hours after surgery. Postoperative pain scores, rescue analgesic requirements, sensory distribution, motor block, nausea and vomiting, quality of recovery, patient satisfaction, and block-related complications will also be evaluated.