Enghien-les-Bains thermal spa treatment for knee osteoarthritis

Evaluation of the Effectiveness of the Enghien-les-Bains Thermal Spa Treatment in the Rheumatology Indication in Patients With Knee Osteoarthritis. Indirect Comparison Study.

This trial will try a 20-day thermal spa program at Enghien-les-Bains to see if it reduces pain and improves function over six months in people aged 50–80 with radiographic knee osteoarthritis and notable functional impairment.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 76 (estimated)
• Ages: 50 Years to 80 Years
• Sex: All
• Sponsor: CEN Biotech (industry)
• Locations: 2 sites (Enghien-les-Bains and 1 other locations)
• Trial ID: NCT07370480 on ClinicalTrials.gov

What this trial studies

This interventional study enrolls adults 50–80 with radiographic knee osteoarthritis (Kellgren–Lawrence grade 2–4) and a baseline normalized WOMAC function score ≥30. Participants undergo a 20-day on-site thermal spa treatment at Thermes d'Enghien-les-Bains with care and adverse events recorded, plus clinical visits at baseline, end of treatment, and six months and a patient-reported check at three months. Effectiveness on pain and functional disability at six months is measured using the Minimal Clinically Important Improvement (MCII) and results are compared indirectly to an external control group from the ANGELLO trial. An ancillary qualitative study collects semi-structured interviews to describe participants' experiences, engagement, facilitators and barriers to benefit.

Who should consider this trial

Good fit: Ideal candidates are adults 50–80 with X‑ray–confirmed knee OA (Kellgren–Lawrence 2–4), a normalized WOMAC physical function score ≥30, health insurance coverage, and no contraindication to balneotherapy.

Not a fit: Patients with contraindications to balneotherapy, other chronic inflammatory rheumatism or fibromyalgia, recent spa treatment, or those scheduled for knee surgery within seven months are unlikely to benefit from this program.

Why it matters

Potential benefit: If successful, the thermal spa program could produce clinically meaningful reductions in pain and improvements in knee function that last at least six months, offering a non-surgical management option.

How similar studies have performed: Previous randomized and observational studies of balneotherapy for knee osteoarthritis have reported modest short-to-medium-term improvements in pain and function, though high-quality direct comparisons with standard care remain limited.

Eligibility criteria

Inclusion Criteria:

* Knee osteoarthritis with Kellgren and Lawrence stage 2 to 4 evidenced by a knee X-ray examination in the past 3 years.
* 100-normalized score of the WOMAC physical function subscale greater than or equal to 30.
* Signed inform consent.
* With health insurance affiliation.

Exclusion Criteria:

* Presented with balneotherapy contraindication or to certain adjuvant treatment techniques (balneation, hydrotherapy jets, massage): chronic infectious pathology, active cancer, decompensated cardiac, hepatic or renal insufficiency, "open" leg ulcer, immune deficiency, phlebitis, erysipelas or history of erysipelas, active thrombosis, behavioral disorders, etc.
* Presented with chronic pain for reasons other than osteoarthritis: chronic inflammatory rheumatism (rheumatoid arthritis, ankylosing spondylitis, lupus, psoriatic arthritis) or fibromyalgia.
* Patient scheduled for knee osteoarthrosis-related surgery within the next 7 months.
* Having had spa treatment in the past 6 months whatever the indication or intra-articular corticosteroid injection within the previous 90 days or hyaluronic acid infiltration or other viscosupplementation or platelet-rich plasma (PRP) injection within the previous 6 months.
* Having planned a spa treatment in another indication between inclusion and final visit.
* Residing more than 30 kilometers from Enghien-les-Bains at the time of spa treatment.
* Women of childbearing potential who are not using effective contraception (estrogen/progestin or progestin-only oral, vaginal, transdermal, injectable or subcutaneous) or who plan to discontinue contraception within the next 7 months.
* Likely to be unable to comply with protocol or to attend visits, particularly in view of the duration of the research, or unable to read or understand French.
* Regulatory reason (guardianship or already enrolled in a clinical trial).
* Already included in a clinical trial or in the exclusion period of a clinical trial.

Where this trial is running

Enghien-les-Bains and 1 other locations

• Thermes d'Enghien-les-Bains — Enghien-les-Bains, France (RECRUITING)
• Thermes d'Enghien-les-Bains — Enghien-les-Bains, Île-de-France Region, France (NOT_YET_RECRUITING)

Study contacts

• Principal investigator: Magali Ballard, MD
• Study coordinator: Christine Juhel, Ph.D

Conditions: Knee Osteoarthritis, spa therapy, thermal treatment, balneotherapy, Rheumatology