Prospective Cohort Study Evaluating a Thermal Spa Programme in Symptomatic Knee Osteoarthritis

Official title

Prospective Cohort Study Evaluating a Thermal Spa Programme for the Management of Symptomatic Knee Osteoarthritis

Overview

Knee osteoarthritis is a common cause of pain, functional limitation, and reduced quality of life in older adults. Thermal spa treatment is widely used as a non-pharmacological intervention for the management of osteoarthritis symptoms, but its effects on joint movement and motor control remain insufficiently characterized using objective biomechanical measures. This study evaluates the effects of a 3-week thermal spa treatment on knee joint movement in patients with knee osteoarthritis. Knee movement fluidity and gait parameters will be analyzed during standardized tasks using wearable inertial sensors (Xsens). Secondary outcomes include changes in pain, physical function, physical activity, quality of life, and blood transcriptomic profiles. Assessments will be performed at baseline, after treatment, and at 3- and 12-month follow-up visits. In addition, blood samples will be collected before and after the intervention to explore transcriptomic changes associated with the treatment. This project proposes a combination of innovative kinematic and biological biomarkers with the aim of objectively describing the benefits of spa therapy for people with knee osteoarthritis.

Interventions

• Device X-sens sensor
  Participants will be equipped with an Xsens wearable motion capture system consisting of eight inertial sensors placed on the feet, shanks, thighs, pelvis, and trunk. Assessments will be conducted before and after the thermal spa treatment and at follow-up visits at 3 and 12 months. Participants will perform standardized functional tasks including level walking (four 20-m round trips), stair ascent and descent (five 15-cm steps), and a chair sit-to-stand task performed without using the hands. E
• Other Transcriptomic
  Approximately 8.5 mL of blood will be collected from each participant before and after the thermal spa treatment. Samples will be pseudonymized using a coded identifier. Total RNA will be extracted and analyzed using transcriptomic approaches (RNA sequencing) to assess gene expression changes associated with the intervention. Differential gene expression analyses will be performed, and selected results may be validated using RT-qPCR
• Other Self-questionnaire
  Self-administered questionnaires will be completed at baseline, after the thermal spa treatment, and at 3- and 12-month follow-up visits. These include: pain intensity measured using a Visual Analog Scale (VAS); osteoarthritis symptoms assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC); physical activity level evaluated with the International Physical Activity Questionnaire - Short Form (IPAQ-SF); and health-related quality of life assessed using the 12-Ite

Primary outcome measures

• Comparison of fluidity of knee joint movement [Time frame: Baseline to post-spa (Day 21)]

Secondary outcome measures (12)

• Change in pain intensity measured by Visual Analog Scale (VAS) [Time frame: Baseline to post-spa (Day 21)]
• Change in pain intensity measured by Visual Analog Scale (VAS) [Time frame: Baseline to 3 months post-spa]
• Change in pain intensity measured by Visual Analog Scale (VAS) [Time frame: Baseline to 12 months post-spa]
• Change in osteoarthritis symptoms measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) [Time frame: Baseline to post-spa (Day 21)]
• Change in osteoarthritis symptoms measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) [Time frame: Baseline to 3 months post-spa]
• Change in osteoarthritis symptoms measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) [Time frame: Baseline to 12 months post-spa]
• Change in physical activity level measured by the International Physical Activity Questionnaire - Short Form [Time frame: Baseline to post-spa (Day 21)]
• Change in physical activity level measured by the International Physical Activity Questionnaire - Short Form [Time frame: Baseline to 3 months post-spa]
• Change in physical activity level measured by the International Physical Activity Questionnaire - Short Form [Time frame: Baseline to 12 months post-spa]
• Change in health-related quality of life measured by the 12-Item Short Form Health Survey (SF-12) [Time frame: Baseline to post-spa (Day 21)]
• Change in health-related quality of life measured by the 12-Item Short Form Health Survey (SF-12) [Time frame: Baseline to 3 months post-spa]
• Change in health-related quality of life measured by the 12-Item Short Form Health Survey (SF-12) [Time frame: Baseline to 12 months post-spa]

Eligibility criteria

Inclusion criteria

• Adults aged 50 years or older
• Diagnosis of knee osteoarthritis affecting at least one knee, with radiographic Kellgren-Lawrence grade ≥ 2 confirmed by an X-ray performed within the past 3 years
• Average knee pain intensity > 30 mm on a 100-mm Visual Analog Scale (VAS) during the month prior to inclusion
• Participants scheduled to undergo a 3-week thermal spa treatment at the Balaruc-les-Bains thermal center

Exclusion criteria

• Use of systemic or injectable corticosteroids within 1 month prior to inclusion
• Intra-articular injection of hyaluronic acid or platelet-rich plasma (PRP) within the 3 months prior to inclusion
• Active inflammatory joint disease (e.g., rheumatoid arthritis, spondyloarthritis, or crystal-induced arthropathies)
• Current major depressive episode or psychotic disorders
• Thermal spa treatment within the previous 6 months
• Inability to read or write
• Inability to complete follow-up for the entire study period (e.g., planned relocation, travel, professional commitments, or residence located more than 100 km from the study site)
• Lack of informed consent
• Pregnant or breastfeeding women
• Individuals under legal protection (guardianship or curatorship)
• Not affiliated with a national health insurance system
• Individuals under judicial protection (safeguard of justice)
• Participation in another clinical study with an ongoing exclusion period

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Other

Study locations

France · 1 center

• Centre thermal de Balaruc les Bains — Balaruc-les-Bains

Identifiers

NCT: NCT07534189 · RECHMPL25_0061 · 2025-A01474-45

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗