mTLIP vs QIPB for Postoperative Analgesia in Lumbar Microdiscectomy Surgery

Comparison of Ultrasound-Guided Modified Thoracolumbar Interfascial Plane Block Versus Quadro-Iliac Plane Block for Postoperative Analgesia in Patients Undergoing Lumbar Microdiscectomy

The aim of this prospective randomized clinical study is to compare the analgesic efficacy and side effects of modified thoracolumbar interfascial plane block and quadroiliac plane block applied preoperatively in patients undergoing lumbar microdiscectomy surgery.The study will include a total of 80 patients aged 18-65 years with ASA I-III, with 40 patients in each group( Group mTLIP and Group QIPB) undergoing lumbar microdiscectomy surgery.

The primary objective of the study is to compare groups in terms of PCA opioid consumption during the 48-hour postoperative period. Secondary objectives are to compare groups in terms of QoR-15 recovery score, dynamic and static numerical rating scale scores, total rescue analgesic use, time to first request for rescue analgesia, length of hospital stay, block and opioid-related side effects and complications, and perioperative remifentanil infusion dose.

Study Overview

• Status: Recruiting
• Conditions: Postoperative Pain Management
• Intervention / Treatment: Procedure: Modified Thoracolumbar Interfascial Plane Block (mTLIP); Procedure: Quadro-Iliac Plane Block (QIPB)

Detailed Description

Lumbar spine surgery is commonly associated with moderate to severe postoperative pain . Inadequate pain control may lead to delayed mobilisation, increased cardiopulmonary complications, and prolonged hospital stay.

Ultrasound-guided regional analgesia techniques, particularly fascial plane blocks, are increasingly used as part of multimodal analgesia in lumbar spine surgery. The thoracolumbar interfascial plane (TLIP) block is an established technique that provides effective analgesia and has been modified to improve its clinical application, resulting in the modified thoracolumbar interfascial plane (mTLIP) block. Previous studies have demonstrated the effectiveness of mTLIP for postoperative analgesia after lumbar spine surgeries.

The quadro-iliac plane block (QIPB) is a recently described ultrasound-guided fascial plane block. Early reports suggest that QIPB may provide effective analgesia in lumbar spine procedures; however, comparative evidence with established techniques remains limited.

This prospective randomized clinical trial aims to compare bilateral ultrasound-guided mTLIP and QIPB performed before the surgery in patients undergoing elective lumbar microdiscectomy surgery under general anesthesia, to evaluate whether QIPB can be considered a safe and effective alternative to mTLIP for postoperative analgesia.

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Merih Yildiz Eglen, MD; Phone Number: +905059340629; Email: meriheg@yahoo.com
• Study Contact Backup: Name: Mursel Ekinci, Assoc prof MD; Phone Number: +905067137596; Email: drmurselekinci@gmail.com

Study Locations

• Turkey (Türkiye)
  • Nilüfer
    • Bursa, Nilüfer, Turkey (Türkiye), 16110
      • Recruiting
      • Bursa City Hospital
      • Contact: Merih Yildiz Eglen, MD; Phone Number: +905059340629; Email: meriheg@yahoo.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age between 18 and 65 years
• Classified as American Society of Anesthesiologists physical status I-III
• Scheduled for elective lumbar microdiscectomy surgery under general anesthesia
• Provision of written informed consent

Exclusion Criteria:

• Use of anticoagulant medications or presence of bleeding diathesis
• Known allergy or hypersensitivity to local anesthetics or opioid drugs
• Infection at the planned block site
• Alcohol or drug dependence
• Cognitive impairment preventing reliable pain assessment
• Pregnancy or lactation
• History of previous lumbar spine surgery
• Diabetes mellitus
• Renal or hepatic insufficiency

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group mTLIP; Patients in this group will undergo bilateral mTLIP block under ultrasound guidance prior to surgery.	Procedure: Modified Thoracolumbar Interfascial Plane Block (mTLIP); This is a fascial plane block in which a local anesthetic is injected into the interfascial plane between the longissimus and iliocostalis muscles. Participants in this group will undergo bilateral modified thoracolumbar interfascial plane blocks (mTLIP) under ultrasound guidance prior to surgery. Under sterile conditions, with the patient in the prone position, the ultrasound probe will be placed in the parasagittal plane at the midpoint of the surgical incision, taking into account the lumbar levels to be operated on. The paraspinal muscles will be identified, and using an in-plane technique, the needle will be advanced into the interfascial plane between the longissimus and iliocostalis muscles. Correct needle placement will be confirmed with saline solution. A total of 40 mL of 0.25% bupivacaine and 5 µg/mL (1:200,000) adrenaline-containing local anesthetic solution (20 mL for each side) will be used for the block procedures.
Experimental: Group QIPB; Patients in this group will undergo bilateral QIPB block under ultrasound guidance prior to surgery.	Procedure: Quadro-Iliac Plane Block (QIPB); This is a fascial plane block is a procedure in which local anesthetic is injected at the point where the quadratus lumborum muscle attaches to the iliac crest, allowing it to spread between the erector spinae and quadratus lumborum muscles. Participants in the QIPB Group will undergo bilateral quadrioliac plane blocks (QIPB) under ultrasound guidance prior to surgery. Under sterile conditions, with the patient in the prone position, a convex ultrasound probe will be placed at the point where the quadratus lumborum muscle attaches to the iliac crest to identify the erector spinae and quadratus lumborum muscles. After confirming the needle placement with saline, a local anesthetic solution containing 0.25% bupivacaine and 5 µg/mL (1:200,000) adrenaline will be administered, total 40 mL (20 mL for each side). The spread of the local anesthetic solution between the erector spinae and quadratus lumborum muscles will be visualized

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
1. Postoperative 48-Hour PCA Opioid Consumption	Description: Total amount of opioid delivered by the patient-controlled analgesia (PCA) device during the first 48 hours after surgery, recorded in milligrams (mg).	Time Frame: Postoperative 0-8, 8-16, 16-24 24-48 hours intervals

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
QoR-15 Recovery Score	The investigators will use the Turkish version of Quality of Recovery (QoR) / QoR-15 questionairre PART A How have you been feeling in the last 24 hours? (0 to 10, where: 0 = none of the time [poor] and 10 = all of the time [excellent]) Able to breathe easily Been able to enjoy food Feeling rested Have had a good sleep Able to look after personal toilet and hygiene unaided Able to communicate with Getting support from hospital doctors and nurses Able to return to work or usual home activities Feeling comfortable and in control Having a feeling of general well-being PART B Have you had any of the following in the last 24 hours? (10 to 0, where: 10 = none of the time [excellent] and 0 = all of the time [poor]) Moderate pain Severe pain Nausea or vomiting Feeling worried or anxious Feeling sad or depressed	Postoperative 24th and 48th hours
Dynamic and static Numeric Rating Scale scores	Description: Numeric Rating Scale (NRS) (0-10; 0= no pain, 10 = the most severe pain felt) pain scores at rest or movement at predefined postoperative hours	0, 2, 4, 8, 16, 24, and 48 hours postoperatively
Total rescue analgesic dose	Description: Despite the use of patient-controlled analgesia (PCA), if the Numeric Rating Scale (NRS) score is ≥4 at any time point, 0.5 mg/kg intravenous meperidine will be administered as rescue analgesia. Total amount of meperidin during the first 24 and 48 hours after surgery, recorded in milligrams (mg).	Time Frame: Postoperative 48 hours
Time of first request for rescue analgesia	Description: Despite the use of patient-controlled analgesia (PCA), if the Numeric Rating Scale (NRS) score is ≥4 at any time point, 0.5 mg/kg intravenous meperidine will be administered as rescue analgesia.	Time Frame: Postoperative 48 hours
Length of Hospital Stay	Description: Length of hospital stay will be defined as the number of days from the end of surgery to hospital discharge	the day of discharge from the hospital (assessed up to 10 days)
Block and Opioid-Related Adverse Effects and Complications	Description: Block- and opioid-related adverse effects and complications, including but not limited to local anesthetic toxicity, hematoma, infection, nerve injury, nausea, vomiting, pruritus, sedation, and respiratory depression, will be recorded	Time Frame: Postoperative 48 hours
Perioperative Remifentanil infusion dose	The amount of remifentanil administered in micrograms during general anesthesia	During surgery

Collaborators and Investigators

• Sponsor: Bursa City Hospital

Publications and helpful links

General Publications

• Alver S, Ciftci B, Celik EC, Sargolzaeimoghaddam M, Cetinkal A, Erdogan C, Ahiskalioglu A. Postoperative recovery scores and pain management: a comparison of modified thoracolumbar interfascial plane block and quadratus lumborum block for lumbar disc herniation. Eur Spine J. 2024 Jan;33(1):118-125. doi: 10.1007/s00586-023-07812-3. Epub 2023 Jun 14.
• Tulgar S, Ciftci B, Ahiskalioglu A, Bilal B, Sakul BU, Girit M, Akin T, Narayanan M, Alici HA. Ultrasound guided quadro-iliac plane block: another novel fascial plane block. Pain Med. 2024 May 3;25(6):370-373. doi: 10.1093/pm/pnae018.
• Turan EI, Sahin AS. Quadro-iliac plane block (QIPB) in lumbar stabilisation surgeries: A case series. Indian J Anaesth. 2025 Feb;69(2):244-245. doi: 10.4103/ija.ija_1077_24. Epub 2025 Jan 29. No abstract available.
• Turan EI, Aslan C, Berber K, Sarban O, Sahin AS. Efficacy of quadro-iliac plane block in single level lumbar discectomies: a case series for novel block. Minerva Anestesiol. 2024 Dec;90(12):1159-1160. doi: 10.23736/S0375-9393.24.18314-9. Epub 2024 Sep 11. No abstract available.
• Ciftci B, Ekinci M. A prospective and randomized trial comparing modified and classical techniques of ultrasound-guided thoracolumbar interfascial plane block. Agri. 2020 Nov;32(4):186-192. doi: 10.14744/agri.2020.72325.

Study record dates

Study Major Dates

• Study Start (Actual): March 25, 2026
• Primary Completion (Estimated): July 25, 2026
• Study Completion (Estimated): September 1, 2026

Study Registration Dates

• First Submitted: March 9, 2026
• First Submitted That Met QC Criteria: March 14, 2026
• First Posted (Actual): March 18, 2026

Study Record Updates

• Last Update Posted (Actual): March 27, 2026
• Last Update Submitted That Met QC Criteria: March 26, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Postoperative pain; Lumbar Microdiscectomy; Modified thoracolumbar interfascial plane block; Quadro-iliac plane block
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain, Postoperative
• Other Study ID Numbers: BursaCityHOS 5

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No