The place of high-resolution thermal imaging in the diagnosis of septic arthritis

Aim: Septic arthritis is an orthopedic emergency with a complex diagnostic and surgical decision-making process. In suspected cases of septic arthritis, arthroscopic debridement is performed because septic arthritis cannot be excluded. The aim of this study is to evaluate temperature changes in the differentiation of septic and non-septic arthritis using a high- resolution thermal camera. Material and Methods: This study included 52 patients with a preliminary diagnosis of arthritis (septic or non-septic) in 2024. The temperature increase in the knee suspected of septic arthritis was evaluated using high-resolution thermal imaging and compared with the contralateral healthy knee. Subsequently, joint culture was obtained through intra-articular puncture to confirm the diagnosis. The demographic characteristics of the cases included in this study (age, gender, height, and weight), time of admission, presenting complaints (knee pain, temperature increase, restricted joint movement, swelling, redness), laboratory evaluation of joint aspiration fluid, and surgery information were recorded. All findings and results were evaluated according to Newman's criteria for septic arthritis, and patient groups were formed as septic and non-septic. Signs: Thermal measurements were compared between 16 patients diagnosed with septic arthritis and 36 patients with aseptic arthritis. The mean temperature was 37.36±0.48 °C in the septic arthritis group and 34.81±1.09 °C in the aseptic arthritis group (p< 0.001). The mean temperature difference in both joints was 4.2 °C in the septic group and 2 °C in the non-septic group (p < 0.001). The mean temperature was measured as 37.4 °C in the septic arthritis group and 34.9 °C in the non-septic arthritis group (p< 0.001). Results: High-resolution thermal imaging devices can be used as a non-invasive diagnostic tool in the diagnosis of septic arthritis. A quantitative value can be obtained to determine the local temperature increase. In future studies, specially designed and more complex thermal devices for septic arthritis can be developed. Keywords: Septic Arthritis, Thermal Measurement, Temperature Increase