Intertrochanteric femur fractures are common in elderly patients and are associated with significant pain. Providing effective analgesia is clinically important both during positioning for spinal anesthesia and in the postoperative period in this patient population.

The Pericapsular Nerve Group (PENG) block is a regional anesthesia technique that targets the articular branches of the hip capsule and may provide effective analgesia with motor-sparing potential. The Deep Iliacus Plane Block (DIPB) is a newer approach that may spread to both the articular branches and the lateral femoral cutaneous nerve.

Although both blocks are used in patients with intertrochanteric fractures, there is a lack of sufficient randomized controlled data comparing their effectiveness for pain during positioning for spinal anesthesia and for postoperative analgesia. Therefore, it is important to determine which technique provides greater clinical benefit.

The aim of this study is to compare the analgesic efficacy of the PENG block and the Deep Iliacus Plane Block during positioning for spinal anesthesia and in the postoperative period in patients undergoing surgery for intertrochanteric femur fractures.

This study was planned as a prospective, single-center, double-blind randomized controlled trial to be conducted in the operating room of Erzincan Mengücek Gazi Training and Research Hospital. The study will commence after obtaining approval from the institutional ethics committee and written informed consent from all patients.

A minimum of 75 patients aged between 18 and 75 years, classified as ASA physical status I, II, or III, who are scheduled for elective surgery under spinal anesthesia for intertrochanteric femur fractures by the Orthopedics and Traumatology Department, will be included in the study.

Patients with ASA IV or higher risk scores, those undergoing emergency surgery, those who refuse participation or wish to withdraw, patients with cognitive dysfunction such as Alzheimer's disease, dementia, or delirium, those with a history of local anesthetic toxicity, infection at the injection site, bleeding diathesis, those undergoing additional surgical or anesthetic procedures (e.g., general anesthesia), patients with chronic opioid use, and those receiving treatment for neuropathic pain will be excluded.

The study will be conducted over a 12-month period between March 1, 2026, and March 1, 2027. All patients will be informed about the study protocol and procedures one day prior to surgery, and written informed consent will be obtained.

Patients admitted to the preoperative preparation room will undergo routine monitoring and will be allocated into three groups according to the analgesic method applied before surgery:

Control group (Group C): intravenous analgesia only Group P: Pericapsular Nerve Group (PENG) block Group D: Deep Iliacus Plane Block (DIPB)

For patients receiving regional blocks, after ensuring sterile conditions, 30 mL of 0.25% bupivacaine will be injected into the appropriate plane under ultrasound guidance.

Patients will be randomized in a 1:1:1 ratio using a computer-generated variable block randomization method (block sizes of 6 and 9). Allocation concealment will be ensured using sequentially numbered, opaque, sealed envelopes (SNOSE method). The randomization list will be prepared by an independent researcher not involved in the study, and envelopes will be opened in the preoperative room immediately before block administration.

All block procedures will be performed by the same anesthesiologist to ensure standardization. The practitioner performing the block will not be involved in intraoperative or postoperative assessments. Intraoperative management, monitoring, and postoperative pain assessments will be conducted by other anesthesiologists participating in the study. The study is designed as double-blind, with both patients and outcome assessors blinded to the type of block performed.

In the operating room, patients will be monitored, and standard hemodynamic parameters (SpO₂, blood pressure, heart rate) will be recorded throughout the perioperative period. Nasal oxygen at 2 L/min will be administered routinely.

At 30 minutes after block application, pain levels will be assessed using the Numerical Rating Scale (NRS). Due to pain and limited mobility associated with femur fractures, motor block will be evaluated using an isometric quadriceps contraction test that does not require joint movement. Patients will be asked, in the supine position, to press their knee downward against the bed ("quad set"), and quadriceps contraction will be assessed by palpation. Motor block will be recorded using a three-point scale:

0 = No contraction

1. = Weak contraction (palpable but not producing significant force)
2. = Normal contraction (strong and clearly palpable)

The Numerical Rating Scale (NRS) is a validated and widely used method in which patients rate their pain from 0 (no pain) to 10 (worst imaginable pain).

Sensory block will be assessed using a cold discrimination test, comparing both sides, and the presence of hypoesthesia or anesthesia at the dermatomal level will be recorded.

Patients will then be positioned in the sitting position for spinal anesthesia, and pain scores during positioning will be recorded. Spinal anesthesia will be performed at the L3-L4 interspace using a 25G pencil-point spinal needle in the sitting position, with administration of 15 mg (3 mL) of 0.5% hyperbaric bupivacaine and 20 mcg (0.4 mL) fentanyl. Surgery will commence after achieving a sensory block level of T10.

Postoperatively, patients will be transferred to the recovery unit as per routine practice. Patients with an Aldrete score >9 will be transferred to the ward. The Aldrete Scoring System evaluates physiological recovery after anesthesia based on five parameters: activity, respiration, circulation, consciousness, and oxygen saturation, each scored from 0 to 2, with a maximum total score of 10.

Postoperative pain will be assessed using the Visual Analog Scale (VAS) at 3, 6, 12, and 24 hours and recorded. All patients will receive routine postoperative analgesia consisting of intravenous ibuprofen 400 mg twice daily.

Additionally, as per standard practice in the orthopedic ward, if the NRS score is ≥4, rescue analgesia will be administered as intravenous tramadol at a dose of 1 mg/kg. The interval between tramadol doses will be at least 6 hours, and the maximum daily dose will not exceed 400 mg.

Within the first 24 postoperative hours, the total amount and types of additional analgesics (NSAIDs or opioids) used for pain control will be recorded. Postoperative evaluations will be performed by physicians who are blinded to the type of block applied.

Inclusion Criteria:

• Patients scheduled for elective surgery for intertrochanteric femur fractures
• Patients with ASA physical status I, II, or III
• Patients aged between 30 and 85 years

Exclusion Criteria:

• Patients with ASA physical status IV or higher
• Patients undergoing emergency surgery
• Patients who refuse to participate or withdraw consent during the study
• Patients with cognitive dysfunction such as Alzheimer's disease, dementia, or delirium
• Patients with a history of local anesthetic toxicity
• Patients with infection at the planned block site
• Patients with bleeding diathesis
• Patients undergoing additional surgical procedures or additional anesthesia (e.g., general anesthesia)
• Patients with a history of chronic opioid use or receiving treatment for neuropathic pain