Comparison of Efficacy of Caudal Versus Transforaminal Epidural Steroid Injections in Unilateral S1 Nerve Root Pain: A Randomized Controlled Trial

October 12, 2026 updated by: Ahmad, University of Health Sciences Lahore

This study compares caudal and transforaminal epidural steroid injections for treating unilateral S1 nerve root pain. It evaluates pain relief, functional improvement, treatment satisfaction, quality of life, and complications over 12 months.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

Unilateral S1 nerve root pain is a common manifestation of lumbosacral radiculopathy and may persist despite conservative treatment. Epidural steroid injections are used as an interventional treatment option for patients with persistent radicular pain. Different approaches to epidural steroid delivery may produce different patterns of pain relief and functional improvement, but their comparative clinical effectiveness in patients with unilateral S1 nerve root pain remains an important clinical question.

This randomized controlled trial was designed to compare two approaches to epidural steroid administration: caudal epidural steroid injection and transforaminal epidural steroid injection. The study focuses on patients with unilateral S1 nerve root pain associated with imaging-confirmed nerve root compression who have persistent symptoms despite conservative management.

The principal purpose of the study is to characterize and compare the clinical response associated with the two injection approaches over an extended follow-up period. The study evaluates changes in pain and functional status together with patient-reported quality of life and satisfaction with treatment. The study also considers the duration and sustainability of treatment effects and documents treatment-related complications and adverse events.

The comparison is intended to provide clinical information regarding the relative effectiveness and safety of the two epidural injection approaches in the management of unilateral S1 nerve root pain. Assessment across multiple follow-up points allows the study to examine both the early response following treatment and the persistence of clinical effects over time.

The study uses a parallel-group randomized controlled design in which eligible participants are allocated to receive either caudal or transforaminal epidural steroid injection. The study procedures, eligibility criteria, outcome measures, follow-up schedule, and statistical methods are described in their respective sections of the clinical trial record.

Study Type

Interventional

Enrollment (Estimated)

120

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • Pakistan
    • Punjab Province
      • Lahore, Punjab Province, Pakistan, 54000
        • Ghurki Trust & Teaching Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 75 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Age 18-75 years.
  • Clinical symptoms and MRI confirmation of unilateral S1 nerve root compression.
  • Pain duration > 6 weeks despite conservative therapy.

Exclusion Criteria:

  • Previous epidural steroid injection in the past 6 months.
  • Significant neurological deficits requiring immediate surgery.
  • Coagulopathy or current anticoagulant therapy.
  • Allergy to corticosteroids or contrast agents.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Group A: Caudal Epidural Steroid Injection (CEI)

Participants receive a caudal epidural steroid injection through the sacral hiatus under fluoroscopic guidance. A corticosteroid combined with a local anesthetic is administered into the epidural space, with contrast dye used to confirm proper needle placement and epidural distribution.
Procedure: Caudal Epidural Steroid Injection (CEI)

A caudal epidural steroid injection is administered through the sacral hiatus into the epidural space under fluoroscopic guidance. Corticosteroid combined with a local anesthetic is administered, and contrast dye is used to confirm proper needle placement.
Active Comparator: Group B: Transforaminal Epidural Steroid Injection (TFI)

Participants receive a transforaminal epidural steroid injection targeting the affected S1 neural foramen under fluoroscopic guidance. A corticosteroid and local anesthetic mixture is administered, with contrast dye used to confirm proper epidural distribution.
Procedure: Transforaminal Epidural Steroid Injection (TFI)

A transforaminal epidural steroid injection is administered into the affected S1 neural foramen under fluoroscopic guidance. A steroid and local anesthetic mixture is administered, with contrast dye used to confirm proper epidural distribution.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Pain intensity measured by Visual Analogue Scale (VAS)
Time Frame: Baseline, 1 week, 1 month, 3 months, 6 months, and 12 months after intervention

Pain intensity will be assessed using the Visual Analogue Scale (VAS) to compare pain relief between caudal epidural steroid injection and transforaminal epidural steroid injection groups.
Baseline, 1 week, 1 month, 3 months, 6 months, and 12 months after intervention

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Oswestry Disability Index (ODI)
Time Frame: Baseline, 1 month, 3 months, 6 months, and 12 months after intervention

Functional disability will be assessed using the Oswestry Disability Index (ODI) to compare functional outcomes between the caudal epidural steroid injection and transforaminal epidural steroid injection groups.
Baseline, 1 month, 3 months, 6 months, and 12 months after intervention
Health-Related Quality of Life measured by SF-36
Time Frame: Baseline, 1 month, 3 months, 6 months, and 12 months after intervention

Health-related quality of life will be assessed using the Short Form-36 (SF-36) questionnaire to compare quality-of-life outcomes between the two treatment groups.
Baseline, 1 month, 3 months, 6 months, and 12 months after intervention
Duration of Pain Relief
Time Frame: From 1 week through 12 months after intervention

The duration and sustainability of pain relief following epidural steroid injection will be assessed and compared between the two treatment groups.
From 1 week through 12 months after intervention
Procedure-Related Complications
Time Frame: From intervention through 12 months after intervention

Procedure-related complications will be recorded and compared between participants receiving caudal and transforaminal epidural steroid injections.
From intervention through 12 months after intervention
Change in Functional Outcome Over 12 Months
Time Frame: Baseline, 1 month, 3 months, 6 months, and 12 months after intervention

Changes in functional status over the follow-up period will be assessed using the Oswestry Disability Index (ODI) and compared between the two treatment groups.
Baseline, 1 month, 3 months, 6 months, and 12 months after intervention

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Health Sciences Lahore

Investigators

  • Study Chair: Dr. Kashif Hussain, Ghurki Trust & Teaching Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

January 5, 2027

Primary Completion (Estimated)

February 2, 2028

Study Completion (Estimated)

February 5, 2028

Study Registration Dates

First Submitted

September 16, 2026

First Submitted That Met QC Criteria

September 16, 2026

First Posted (Actual)

September 22, 2026

Study Record Updates

Last Update Posted (Actual)

October 16, 2026

Last Update Submitted That Met QC Criteria

October 12, 2026

Last Verified

October 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 01-07-2025

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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