The Thermo-Young study is a a cross-sectional observational study of healthy volunteers of both sexes. This study aims to assess the temperature of various areas of the knee using thermographic imaging. The aim of the study is to analyze thermographic images of the knees of healthy volunteers in order to establish reference values for the field, while examining the influence of gender and physical exercise on these values.

The study plans to enroll 60 patients-30 women and 30 men-aged 18 to 35 with no history of previous surgery or chronic knee pain. Once informed consent has been obtained from the healthy volunteer, the volunteer will wait for 10 minutes while seated in a temperature-controlled room set at 25°C. A thermographic assessment will then be performed using a FLIRT1020 thermal imaging camera. Images will be captured from the anteroposterior, right lateral, left lateral, and posteroanterior views. The patient will then perform a knee flexion-extension exercise against resistance for 2 minutes using a 2-kg ankle weight. The speed of this exercise will be constant for all subjects, with one repetition per second per leg. Following this exercise, four additional thermographic images identical to the first set will be acquired. Baseline thermographic assessments will be performed at the end of the exercise, and at 2, 5, and 10 minutes after the end of the exercise. Once the images have been acquired, they will be analyzed using ResearchIR software. Regions of interest within the knee will then be defined, and the temperature distribution across the various images will be analyzed, along with how this distribution changes following physical exertion.

Inclusion Criteria:

1. Male or female patients aged 18 to 35;
2. No history of previous surgery on either knee;
3. No history of direct or indirect trauma to either knee in the preceding six months;
4. Absence of knee symptoms (VAS pain score of 0) and no history of acute or chronic knee pain in either knee;
5. BMI between 18.5 kg/m² and 30.0 kg/m²

Exclusion Criteria:

1. Consumption of hot beverages or alcohol within 4 hours prior to the measurement;
2. Use of anti-inflammatory medications within 48 hours prior;
3. No strenuous physical activity within 48 hours prior to the thermographic evaluation;
4. No history of cardiovascular disease;
5. Skin inflammation in the knee area;
6. Chronic ligament injuries to the knee;
7. Advanced cartilage lesions according to the Outerbridge classification (Grade IV);
8. Incorrect axial alignment of the lower limb;
9. Local or systemic infection;
10. Systemic administration of corticosteroids or immunosuppressive drugs within 30 days prior to the measurement;
11. history of rheumatoid arthritis, inflammatory arthritis, or autoimmune diseases;
12. neurological disorders or conditions that may compromise the research protocol;
13. pregnancy.

healthy volunteers