A comparison of thermographic characteristics of the hands and wrists of rheumatoid arthritis patients and healthy controls

Abstract

Thermal imaging has been applied to detect possible temperature variations in various rheumatic disorders. This study sought to determine whether rheumatoid arthritis (RA) patients without active synovitis in their hands exhibit different baseline thermographic patterns of the fingers and palms when compared to healthy individuals. Data from 31 RA patients were compared to that of 51 healthy controls. The RA patients were recruited upon confirmed absence of synovitis by clinical examination and musculoskeletal ultrasound. Participants underwent medical infrared imaging of the regions of interest (ROIs). Significant differences were found between the mean temperatures of the palm regions (29.37 °C (SD2.2); n = 306) and fingers (27.16 °C (SD3.2); n = 510) of the healthy participants when compared to the palm regions (31.4(SD1.84)°C; n = 186) and fingers (30.22 °C (SD2.4); n = 299) of their RA counterparts (p = 0.001), with the latter group exhibiting higher temperatures in all ROIs. Logistic regression models confirm that both palm and finger temperature increase significantly in RA without active inflammation. These innovative findings provide evidence that baseline thermal data in RA differs significantly from healthy individuals. Thermal imaging may have the potential to become an adjunct assessment method of disease activity in patients with RA.

Thermal characteristics of rheumatoid feet in remission: Baseline data

“…Our results have clearly shown that RA feet without active synovitis exhibit higher temperatures than healthy individuals. These results concur with Gatt et al [ 11 ], who explored joints of the hands and fingers of RA subjects without inflammation and have thus likewise set a baseline for normative RA thermal characteristics of the hands. A recent paper has also found significant differences in the temperature of feet between RA participants with inflammation and healthy participants, however it should be noted that their methodology differed somewhat to this study in that they analyzed temperatures through a dorsal approach [ 9 ].…”

“…The authors postulate that one cannot apply thermography to detect joint inflammation in RA when the baseline data pertaining to RA itself is unknown. As has been demonstrated [ 11 ], patients with RA may exhibit changes in thermographic patterns even in the absence of active inflammation. Hence the need to perform this same research to characterize thermal patterns in the feet of RA patients without active inflammation becomes very clear.…”

“…However, the use of thermography in RA has not been explored sufficiently and the available literature is still conflicting and sometimes contradictory [1,[8][9][10], resulting in inconclusive results [9]. This has precluded the application of this technology to be utilized in this field, as opposed to other fields in which today this technology is gaining in importance [3,11]. This may be due to the lack of such "normative data for RA feet" which establish a baseline against which experimental groups in studies may be compared.…”

“…Gatt et al [ 11 ] report significantly elevated hand and finger temperatures in a cohort of RA subjects without active synovitis compared to healthy adults. Clearly the literature about the effectiveness of thermography in detecting joint inflammation is sparse, especially with regards to foot inflammation.…”

Role of thermography in the assessment of temporomandibular disorders and other musculoskeletal conditions: A systematic review

“…Based on this evidence, it has been suggested that IRT might have an important role in assessing large and medium joints, lacking effectiveness in the context of small joints. 20,21,33,39 Apart from the diagnostic value of IRT discussed above, its prognostic potential to conduct patient follow-up and/or assess treatment outcomes has been also emphasized by others. IRT is an useful and objective supplementary method to support capacity evaluations to perform work-related activities.…”