TcPRF for Knee Osteoarthritis

January 10, 2026 updated by: Martina Rekatsina, National and Kapodistrian University of Athens

Randomized Double-Blind Study to Evaluate the Efficacy of Transcutaneous Pulsed Radiofrequency (PRF) Treatment for Knee Pain

Objectives

  • Primary Objective: To evaluate the efficacy of transcutaneous PRF treatment in reducing knee pain compared to a sham intervention
  • Secondary Objectives: To assess the improvement in functional outcomes and patient satisfaction following PRF treatment.

Study Design

  • Type: Randomized, double-blind, sham-controlled study.
  • Duration: 6 months
  • Study Population: Adults aged 40-75 years with chronic knee pain (lasting ≥ 6 months) due to osteoarthritis (OA).
  • How many patients in each group: 25 patients in each group (according to Janssens et al, 2024) Inclusion Criteria
  • Diagnosed with knee osteoarthritis according to NICE criteria.
  • Chronic knee pain (Visual Analogue Scale [VAS] ≥ 4).
  • Failure to respond adequately to conventional treatments (e.g., NSAIDs, physical therapy).
  • Willingness to comply with study procedures. Exclusion Criteria
  • Previous PRF/RF treatment for knee pain.
  • Hyaluronic acid injection for knee pain in the past 6 months
  • Knee surgery within the last 6 months.
  • Severe cardiovascular, neurological, or psychiatric conditions.
  • Active systemic infections or local skin infections at the knee.
  • Pregnancy or lactation.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Enrolling by invitation

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Randomization and Blinding

  • Randomization: Participants will be randomly assigned to one of two groups: PRF treatment or sham.
  • Blinding: Both participants and investigators will be blinded to the treatment allocation. The device used for PRF treatment will have an identical appearance for both the active and sham groups, but the sham electrode will not deliver active treatment.

Intervention Both groups will receive disposable electrodes on either side of the knee: one skin electrode on the inside and one on the outside of the knee.

  • PRF Group: Participants will receive PRF treatment using a specific protocol (e.g., 3 Hz, 5 ms, 15 minutes, 3 sessions with 1 week and 3 weeks interval). The output will be adjusted according to the distance between electrodes in cm. This will be between 0.7A (circumference 23cm) and 1.4A for 38cm (Spring 2, Clinical Guidelines, Table 1)
  • Sham Group: Participants will receive a sham treatment using a device identical in appearance but without delivering the actual PRF therapy.

Outcome Measures Primary Outcome • Pain Reduction: Measured using the NRS (numerical rating scale) at baseline, immediately after treatment, and at follow-up intervals (2 weeks, 4 weeks, 8 weeks, 12 weeks).

Secondary Outcomes

  • Functional Improvement: Assessed using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores.
  • Patient Satisfaction: Measured using a Likert scale for overall satisfaction with treatment.
  • Global Assessment: Patient's global assessment of change in pain and function.
  • Medication reduction Sample Size Calculation
  • Estimate: Based on previous studies and expected effect size, calculate the necessary sample size to achieve a power of 80% and a significance level of 0.05. The sample size must account for potential dropouts.

Data Collection and Management

  • Data will be collected at baseline, post-treatment, and during follow-up visits.
  • Use electronic case report forms (eCRFs) for data entry.
  • Ensure the security and confidentiality of participant data. Statistical Analysis
  • Primary Analysis: Compare the mean change in VAS scores between the PRF and sham groups using an independent t-test or ANCOVA, adjusting for baseline values.
  • Secondary Analysis: Compare changes in WOMAC scores and patient satisfaction between groups using similar statistical methods.
  • Responder Analysis: Define responders as those with ≥30% reduction in VAS scores from baseline and compare proportions between groups using a chi-square test.
  • Intention-to-Treat (ITT) Analysis: Include all randomized participants in the analysis based on the treatment they were allocated, regardless of whether they completed the study.

Ethical Considerations

  • Obtain informed consent from all participants.
  • Ethical approval from a recognized Institutional Review Board (IRB) is required.
  • Ensure that participants can withdraw at any time without affecting their standard care.

Monitoring and Safety

  • Adverse Events: Monitor and record all adverse events during the study.
  • Data Safety Monitoring Board (DSMB): Establish a DSMB to review safety data periodically.

Dissemination of Results

• Results will be published in a peer-reviewed journal and presented at relevant conferences within a year after results are known. Data will be reported according to CONSORT guidelines.

Timeline

  • Recruitment Period: 3 months
  • Intervention Period: 4 weeks
  • Follow-up Period: 3 and 6 months
  • Data Analysis and Reporting: 3 months after study completion.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
50

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • 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 Locations

  • Greece
      • Athens, Greece
        • ARETAIEION University Hospital

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria

  • Diagnosed with knee osteoarthritis according to NICE criteria.
  • Chronic knee pain (Visual Analogue Scale [VAS] ≥ 4).
  • Failure to respond adequately to conventional treatments (e.g., NSAIDs, physical therapy).
  • Willingness to comply with study procedures. Exclusion Criteria
  • Previous PRF/RF treatment for knee pain.
  • Hyaluronic acid injection for knee pain in the past 6 months
  • Knee surgery within the last 6 months.
  • Severe cardiovascular, neurological, or psychiatric conditions.
  • Active systemic infections or local skin infections at the knee.
  • Pregnancy or lactation.

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: Quadruple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Active Comparator: TcPRF
Transcutaneous pulsed RF -connected to treatment mode of the spring pulsed rf generator
Device: Transcutaneous Pulsed Radiofrequency (PRF) Treatment for Knee Pain
application of TcPRF patches
Sham Comparator: TcPRF sham
sham of transcutaneus pRF- connected to demo mode of the spring pulsed rf generator
Device: sham treatment of pulsed rf on knee
Transdermal patch will be connected to demo mode of the spring pulsed rf generator. no treatment will be given

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Pain Reduction
Time Frame: 12 weeks
Measured using the NRS (numerical rating scale) at baseline, immediately after treatment, and at follow-up intervals (2 weeks, 4 weeks, 8 weeks, 12 weeks).
12 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Functional Improvement
Time Frame: 12 weeks
Assessed using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores.
12 weeks
• Patient Satisfaction
Time Frame: 12 weeks
Measured using a Likert scale for overall satisfaction with treatment.
12 weeks

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
National and Kapodistrian University of Athens

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)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 15, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 1, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
June 1, 2026

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
January 10, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 10, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 20, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
January 20, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 10, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 695/24-07-2025

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

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.

Clinical Trials on Knee Osteoarthristis

Clinical Trials on Transcutaneous Pulsed Radiofrequency (PRF) Treatment for Knee Pain

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings