Thermal Characteristics of the Small Joints of the Hands Between Patients with Rheumatoid Arthritis and Healthy Controls.

Sevcan Uğur1, Yakup İrim2, Ayşe Ayça Yücel3, Hamza Feza Carlak4, Cahit Kaçar5

1Antalya City Hospital, Rheumatology, Antalya, Türkiye
2Sinop University, Electronics and Automation, Sinop, Türkiye
3Antalya Training and Research Hospital, Rheumatology, Antalya, Türkiye
4Akdeniz University, Electrical-Electronics Engineering, Antalya, Türkiye
5Akdeniz University, Physical Medicine and Rehabilitation, Division of Rheumatology, Antalya, Türkiye

Keywords: Rheumatoid arthritis, Small joints of the hands, Thermal imaging

Abstract

Objectives: This study aimed to investigate the thermal characteristics of the small joints of the hands between patients with Rheumatoid arthritis and healthy controls.

Patients and Methods: Fifty-two patients with Rheumatoid arthritis and twenty-six healthy controls were included in the study. Joint tenderness was evaluated using Ritchie Articular index. Joint tenderness was scored from 0 to 3. Thermal data was collected from the hand regions of individuals. A FLIR T450sc microbolometer infrared thermal camera with 320x240 resolution was used for the thermography of individuals. Bilaterally proximal interphalangeal joints (1-5) and metacarpophalangeal joints (1-5) were evaluated. The mean temperature was compared between patients and healthy controls

Results: The mean temperature values of the joints in the patients with a Rheumatoid arthritis RAI score of 0, 1, 2,3 were 32.43 ± 1.59°C; 32.71 ± 1.36°C; 33.12 ± 1.23°C; 33.60 ± 0.99 respectively. The mean temperature was 31.14 ± 1.51°C in healthy controls. The mean temperature values of the joints in the Rheumatoid arthritis patients with RAI score of 0 was higher compared to healthy controls (p<0.05). Patients with a Ritchie sensitivity score of 1 had a higher mean temperature compared to patients with score of 0 (p<0.05). In Rheumatoid arthritis patients, the joints with a RAI score of 1 had higher mean temperature values than the joints with RAI score of 0 (p<0.05). The mean temperature values of the joints with RAI score of 2 were also higher than the joints with RAI score of 1 (p<0.05).

Conclusion: Thermal imaging may be an objective tool for diagnosis and assessing disease activity in Rheumatoid arthritis.