The scientific study by Petrigna et al. (2024) focuses on the use of infrared thermography as a pre-diagnostic tool for knee osteoarthritis (OA).

Science has identified a specific thermal alarm threshold. If your knee temperature reaches or exceeds this level, it could be an early sign of osteoarthritis. Despite the studies reviewed using different cameras and protocols, the median temperature was remarkably consistent: 31.3 ± 1.7°C.

Temperature Distribution in OA Patients

The study analyzed 9 research papers. The range of mean temperatures among OA patients was distributed as follows:

• < 31.2°C | Low Temperatures: Frequently observed in advanced stages or patients with a high BMI.
• 31.2°C – 31.5°C | Attention Zone: The second tercile of the reviewed studies.
• > 31.5°C | High Temperatures: Common in cases of symptomatic OA or active inflammation.

Values in the research fluctuated from 28.7°C (in patients with less inflammation or higher BMI) to 34.7°C (in cases of acute inflammation).

Factors That Influence Results

It is important to note that several variables can alter the thermal reading:

• Body Mass Index (BMI): Higher body fat typically results in lower skin temperature.
• Disease Stage: The knee tends to be warmer at the onset of OA and colder when the degenerative process is very advanced.
• Protocol: For accuracy, a 10–15 minute acclimatization period in a room at 22–23°C is recommended before taking the image.

Table studies reviews

Detecting the problem early allows for the implementation of adapted exercise programs to slow down cartilage wear.

This research highlights the potential of infrared thermography for the control and monitoring of knee health. It serves as a fast, non-invasive pre-diagnostic tool to detect degenerative processes before they become disabling.

References

Petrigna L, Amato A, Roggio F, Trovato B, Musumeci G. Thermal threshold for knee osteoarthritis people evaluated with infrared thermography: A scoping review. J Therm Biol. 2024 Jul;123:103932. doi: 10.1016/j.jtherbio.2024.103932. Epub 2024 Aug 3. PMID: 39111061.