Infrared thermal imaging as a screening tool for paediatric wrist fractures

Wrist injuries are common in paediatric trauma, however only half of children evaluated with an x-ray for possible fractures will have one. Thermal imaging offers a possible non-ionising method of screening for fractures and thus reducing negative x-ray rates. 105 children attending the Emergency Department for wrist injuries were recruited. Two 30s thermal videos were recorded from injured and uninjured wrists – in flat and 45o elevated positions. A region of interest (ROI) was defined on each wrist. Cases in which the ROI was covered or had ice applied, were excluded, leaving 40 patients for analysis. Comparisons of ROI included (i) injured and uninjured wrists - flat and elevated positions; (ii) as in (i) with a reference region on the proximal forearm subtracted; (iii) injured wrist ROI - flat and elevated positions. Fractures and sprains increased the mean skin surface temperature by 1.519% (p=0.008) and 0.971% (p=0.055) respectively compared with the uninjured wrist. The mean temperature difference between flat and elevated positions for fractures was 0.268% and -0.1291% for sprains. This difference was statistically significant for fracture (p=0.004) but not sprain (p=0.500). The temperature differences recorded by thermal imaging between fractured and sprained wrists may assist in differentiation of these injuries.