Trial Review

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Trial registered on ANZCTR


Registration number
Help: Registration number
ACTRN12625001437459
Ethics application status
Help: Ethics application status
Approved
Date submitted
Help: Date submitted
21/10/2025
Date registered
Help: Date registered
18/12/2025
Date last updated
Help: Date last updated
1/09/2026
Date data sharing statement initially provided
Help: Data sharing statement date
18/12/2025
Type of registration
Help: Type of registration
Retrospectively registered

Titles & IDs
Public title
The Effectiveness of Retrolaminar and Modified Thoracolumbar Interfascial Plane Blocks in the Management of Opioid-Free Anesthesia in Lumbar Discectomy
Scientific title
Comparison of the Effects of Retrolaminar and Modified Thoracolumbar Interfascial Plane Blocks on Postoperative Pain and Recovery Under Opioid-Free Anesthesia Management in Patients Undergoing Lumbar Discectomy: A Prospective, Double-Blind Study
Additional trial identifiers [1] 315655 0
Nil known
Universal Trial Number (UTN)
Trial acronym
RLB versus MTLIP
Related trial records

Health condition
Health condition(s) studied:
Lumbar Discectomy 339333 0
intervertebral disc displacement 339334 0
Condition category
Condition code
Anaesthesiology 335584 335584 0 0
Pain management
Musculoskeletal 336004 336004 0 0
Other muscular and skeletal disorders

Intervention/exposure
Study type
Interventional
Description of the intervention or exposure
Group Retrolaminar Block (RLB):
Participants in this group will receive an ultrasound-guided bilateral Retrolaminar Block (RLB) prior to the induction of general anaesthesia. The procedure involves the injection of 18 mL %0.25 bupivakain, 2 mL (8 mg) deksametazon on each side into the retrolaminar space at the L3 vertebral level using an in-plane technique. The injection is performed under sterile conditions using a linear ultrasound probe to visualize the lamina and ensure correct needle placement.
- Drug: 18 mL %0.25 bupivakain, 2 mL (8 mg) deksametazon; 20 mL per side
- Mode of administration: Single-shot injection, ultrasound-guided
- Timing: Applied once after general anesthesia induction and intubation.
- Monitoring adherence: Procedure details and drug dosage are recorded in patient medical records and anaesthesia charts.
Intervention code [1] 332268 0
Treatment: Other
Description of the comparator or control
Modified Thoracolumbar Interfascial Plane (mTLIP) Block:
This group serves as the comparator group. Participants receive an ultrasound-guided bilateral mTLIP block at the L3 vertebral level, involving a single injection of 18 mL %0.25 bupivakain, 2 mL (8 mg) deksametazon per side into the interfascial plane between the multifidus and longissimus muscles, performed prior to induction of general anaesthesia.
Mode of administration: Ultrasound-guided single-shot injection
Dose and timing: 18 mL %0.25 bupivakain, 2 mL (8 mg) deksametazon per side, administered once after anaesthesia induction and intubation
Comparator type: Active comparator (comparison between two established regional anaesthesia techniques)
Justification: mTLIP is an established regional anaesthesia technique recommended by current guidelines and used as a comparator to assess effectiveness and recovery-related outcomes versus the Retrolaminar block.
Control group
Active

Outcomes
Primary outcome [1] 343137 0
Visual Analog Scale (VAS)
Timepoint [1] 343137 0
every 5 minutes postoperatively until the Aldrete score is 9 or above
Secondary outcome [1] 453508 0
Time to Verbal Response After Discontinuation of Sevoflurane
Timepoint [1] 453508 0
every minute from 0-15 minutes postoperatively
Secondary outcome [2] 453509 0
Time to Discharge From Post-Anesthesia Care Unit (PACU)
Timepoint [2] 453509 0
every 10 mins from 0-90 minutes postoperatively until discharged from PACU
Secondary outcome [3] 454733 0
Tracheal Extubation Time
Timepoint [3] 454733 0
every minute immediately after cessation of anesthesia
Secondary outcome [4] 454734 0
Postoperative VAS Scores at Specific Time Intervals
Timepoint [4] 454734 0
At 30 min, 2 h, 4 h, 8 h, 12 h, and 24 h postoperatively
Secondary outcome [5] 454735 0
First Rescue Analgesic Request
Timepoint [5] 454735 0
Within the first 24 hours postoperatively
Secondary outcome [6] 454736 0
Total 24-Hour Analgesic Consumption
Timepoint [6] 454736 0
0 to 24 hours postoperatively
Secondary outcome [7] 454737 0
Postoperative Nausea and Vomiting (PONV)
Timepoint [7] 454737 0
Within 24 hours postoperatively

Eligibility
Key inclusion criteria
- Adults aged 18–65 years
- ASA (American Society of Anesthesiologists) physical status I–II
- Scheduled for elective one- or two-level lumbar discectomy under general anesthesia
- Able to understand and provide written informed consent
- Able to complete preoperative pain sensitivity assessments (PSQ, VAS)
Minimum age
18 Years
Maximum age
65 Years
Sex
Both males and females
Healthy volunteers
No
Key exclusion criteria
- Patients with contraindications to block application (local infection, coagulopathy, allergy, etc.)
- Patients with previous lumbar spine surgery
- Patients with a history of opioid addiction or chronic pain management
- Patients who are pregnant or lactating
- Patients who cannot understand scoring tests due to mental retardation or communication difficulties
- Patients who underwent a different anesthesia strategy due to an unplanned complication during the case
- Patients who experienced significant blood loss (>1000 mL) or required intensive care during surgery
- Patients who cannot actively participate in the research process or who cannot be monitored regularly

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
sealed opaque envelopes
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (https://www.randomizer.org; Research Randomizer )
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
20/11/2025
Date of last participant enrolment
Anticipated
4/05/2026
Actual
30/03/2026
Date of last data collection
Anticipated
5/05/2026
Actual
31/03/2026
Sample size
Target
70
Accrual to date
Final
70
Recruitment outside Australia
Country [1] 27473 0
Turkey
State/province [1] 27473 0
Izmir

Funding & Sponsors
Funding source category [1] 320252 0
University
Name [1] 320252 0
Dokuz Eylul University
Country [1] 320252 0
Turkey
Primary sponsor type
Individual
Name
Onur KUCUK (Dokuz Eylül University)
Address
Country
Turkey
Secondary sponsor category [1] 322821 0
None
Name [1] 322821 0
Address [1] 322821 0
Country [1] 322821 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 318799 0
Dokuz Eylül University Clinical Research Ethics Committee
Ethics committee address [1] 318799 0
Ethics committee country [1] 318799 0
Turkey
Date submitted for ethics approval [1] 318799 0
03/09/2025
Approval date [1] 318799 0
16/09/2025
Ethics approval number [1] 318799 0
2025/18-02

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 145294 0
Dr Onur KUCUK
Address 145294 0
Dokuz Eylül University, Inciralti, Mithatpasa Street. number:56, 35330 Balcova/Izmir - Turkey
Country 145294 0
Turkey
Phone 145294 0
+902324122828
Fax 145294 0
Email 145294 0
[email protected]
Contact person for public queries
Name 145295 0
Onur KUCUK
Address 145295 0
Dokuz Eylül University Mithatpasa street number:1606 Balçova, Turkey 35330
Country 145295 0
Turkey
Phone 145295 0
+902324122828
Fax 145295 0
Email 145295 0
[email protected]
Contact person for scientific queries
Name 145296 0
Onur KUCUK
Address 145296 0
Dokuz Eylül University Mithatpasa Street number:1606 35330 Balcova/Izmir - Turkey
Country 145296 0
Turkey
Phone 145296 0
+902324122222
Fax 145296 0
Email 145296 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No
No IPD sharing reason/comment: It is not legal due to the personal data protection law in our country.



What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.