Unipolar Versus Bipolar Radiofrequency Ablation in Knee Osteoarthritis Pain

August 29, 2026 updated by: Mohammed Said ElSharkawy, Tanta University

Unipolar Versus Bipolar Radiofrequency Ablation in Knee Osteoarthritis Pain: A Randomized Single-Blinded Trial

This study aims to compare the efficacy of unipolar versus bipolar radiofrequency ablation (RFA) in knee osteoarthritis pain.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

Osteoarthritis (OA) is one of the most common underlying causes of chronic knee pain resulting in loss of ability. Chronic knee pain due to OA is a debilitating disease. Many therapeutic options have been used to manage this pain such as physical therapy, non-steroid anti-inflammatory drugs (NSAIDs), tramadol, opioids, intraarticular hyaluronic acid, and steroids.

Radiofrequency ablation (RFA) appears to be effective for treatment of knee pain. It acts by interrupting the pain conduction through production of a thermal lesion to interrupt nociceptive signals.

A diagnostic genicular nerve block with local anesthetic is performed before genicular nerve RFA, and a positive result indicates the need for genicular RFA In conventional monopolar RFA (MRFA) technique, the localization of genicular nerves is one through sensory stimulation at the junction of epicondyle with the shaft of femur bone (near periosteum).

Study Type

Interventional

Enrollment (Estimated)

64

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 Locations

  • Egypt
    • El-Gharbia
      • Tanta, El-Gharbia, Egypt, 31527

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

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Age > 50 years.
  • Both genders.
  • Diagnosed with chronic knee osteoarthritis (KOA) according to the American College of Rheumatology (ACR) criteria and confirmed with plain radiography as the gold standard for the diagnosis of KOA.
  • One chronic KOA pain not responding to other treatments as physiotherapy, oral analgesics, and intraarticular injection with hyaluronic acids or steroids.
  • Kellgren-Lawrence grade (II-IV).

Exclusion Criteria:

  • Chronic knee pain induced by infection, inflammation, tumors, and fractures.
  • Prior knee surgery.
  • Acute knee pain.
  • Connective tissue diseases.
  • Neurologic or psychiatric disorders.
  • Intra-articular knee corticosteroid or hyaluronic acids in the past 3 months.
  • Anticoagulant medication.
  • Local infection of the site of intervention.
  • Cognitive impairment.

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
Experimental: Unipolar RFA (URFA) Group
Patients will undergo radiofrequency ablation (RFA) of three genicular nerves (superior medial, superior lateral and inferior medial) with one cannula.
Procedure: Unipolar radiofrequency ablation
Patients will undergo radiofrequency ablation (RFA) of three genicular nerves (superior medial, superior lateral and inferior medial) with one cannula.
Experimental: Bipolar RFA (BRFA) Group
Patients will undergo radiofrequency ablation (RFA) as unipolar RFA but with two cannulas.
Procedure: Bipolar radiofrequency ablation
Patients will undergo radiofrequency ablation (RFA) as unipolar RFA but with two cannulas.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Proportion of successful responders with a reduction 50% of pain
Time Frame: 24 weeks after the procedure
The proportion of successful responders with a reduction 50% of Visual Analog Scale (VAS) will be recorded.
24 weeks after the procedure

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Degree of pain
Time Frame: 24 weeks after the procedure
Knee pain will be measured by visual Analog Scale (VAS) (0 - no pain to 10-worst imaginable pain) at baseline, 1, 4, 12 and 24 weeks after the procedure during movement.
24 weeks after the procedure
Oxford Knee Score (OKS)
Time Frame: 24 weeks after the procedure
The functional changes in the knee will be assessed by Oxford Knee Score (OKS). It is simple, valid, self-administered, joint-specific 12-item questionnaires ranging from 12 to 60, with 12 referred to the best result.
24 weeks after the procedure

Collaborators and Investigators

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

Sponsor

Tanta University

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)

August 29, 2026

Primary Completion (Estimated)

June 1, 2027

Study Completion (Estimated)

June 1, 2027

Study Registration Dates

First Submitted

August 24, 2026

First Submitted That Met QC Criteria

August 24, 2026

First Posted (Actual)

August 27, 2026

Study Record Updates

Last Update Posted (Actual)

September 1, 2026

Last Update Submitted That Met QC Criteria

August 29, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 36265PR110/6/26

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

The data will be available upon a reasonable request from the corresponding author after the end of study for one year.

IPD Sharing Time Frame

After the end of study for one year.

IPD Sharing Access Criteria

The data will be available upon a reasonable request from the corresponding author.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL

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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