CompletedNot Applicable

tDCS for Pain Modulation in Knee Osteoarthritis

Egypt102 participantsStarted 2025-12-20

Plain-language summary

Knee osteoarthritis (KOA) is a common condition that causes long-lasting knee pain and difficulty with daily activities. Many patients have pain that is stronger than expected from joint changes because the nervous system becomes more sensitive to pain. Transcranial direct current stimulation (tDCS) is a non-invasive technique that uses a small electrical current applied to the scalp to help reduce pain sensitivity. This study will test whether active tDCS over the primary motor cortex can reduce pain and improve function in people with knee osteoarthritis. A total of 102 participants will be randomly assigned to receive either active tDCS or sham (placebo) stimulation. All participants will receive 15 sessions over three weeks. We will measure pain intensity, pain sensitivity, physical function, depression, cognition, and quality of life before the treatment, after the 3-week treatment program, and again at the 1-month follow-up.

Who can participate

Age range

35 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Diagnosis of knee osteoarthritis (KOA) according to the American College of Rheumatology (ACR) clinical criteria. * Adults of both sexes aged 35 years or older. * Clinical knee pain persisting for at least 3 months. * Average knee pain intensity ≥ 4/10 on the Numerical Rating Scale (NRS; 0-10) during the previous 24 hours, with one dominant affected knee. * Central sensitization phenotype: impaired conditioned pain modulation (CPM), defined as no change or a reduction in pressure pain threshold (PPT) after the conditioning stimulus, corresponding to a PPT ratio ≥ 1 (pre-to-post stimulus). * Prior pharmacological pain management with NSAIDs and/or SNRIs discontinued due to adverse effects, intolerance, or contraindications, and able to complete the required washout period (2 weeks for NSAIDs and 4 weeks for SNRIs) before baseline assessment. * Able and willing to provide written informed consent and comply with study procedures. Exclusion Criteria: Participants will be excluded if they have any condition that could affect cortical excitability, confound outcome measures, or interfere with tDCS safety, including: * Other chronic pain conditions associated with central sensitization (e.g., fibromyalgia). * Inflammatory arthropathies (e.g., rheumatoid arthritis, psoriatic arthritis, systemic lupus erythematosus). * Neuropathic pain syndromes (e.g., lumbar or cervical radiculopathy). * Any clinically significant or unstable systemic disease (cardiovascula…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Change in Pain Intensity (VAS and BPI Scores)

Timeframe: Baseline, immediately after the 15-session intervention, and at 1-month follow-up.

Trial details

NCT IDNCT07291791

SponsorSuez Canal University

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2026-05-20

View on ClinicalTrials.gov More Knee Osteoarthritis trials