Thermal Imaging as a Noninvasive Diagnostic Tool for Anterior Knee Pain Following Implantation of Artificial Knee Joints

Abstract

The variety of radiographic diagnostics used to diagnose pain localised close to metal implants is still limited. Especially magnetic resonance results can not be analysed because of artefacts. In this article we present for the first time a direct correlation between an increase in skin temperature and existent frontal (anterior) knee pain after implantation of artificial knee joints measured with thermography. In a standardised way 26 knees were analysed. Thermographic photos were taken from frontal, inner (medial) and outer (lateral) directions with a computer-assisted infrared thermograph. Temperatures in locations with pain were significantly higher compared to the reference field in inner location (median 0.95 °C, p=0.0043), as well as in outer location (median 0.5 °C, p=0.032). Median temperature difference between pain localization and localizations without pain was 0.7 °C and ranged from 0.1 °C to 1.7 °C. In the receiver operating characteristic (ROC) analysis the sensitivity of this method was 1.0 and specificity was 0.917. The evidence of a significant increase in skin temperature on the painful sites opens up the possibility to localize and assess pain more precisely in patients with joint prosthesis. We consider this novel, rapid, inexpensive and non-invasive technology to posses the potential to become a useful and objective tool for diagnosis of pain and inflammation and to generate digital data that can be stored and analysed in clinical practice.

Quantitative Estimation of Temperature Variations in Plantar Angiosomes: A Study Case for Diabetic Foot

“…Since the estimated temperature of an angiosome is known, it is possible to have the estimated temperature difference (ETD) of the corresponding angiosomes between both feet to determine if the difference is normal [20] $\begin{array}{c}\text{ETD}=\left|\text{E}{\text{T}}_{\text{left}\mathrm{\hspace{0.17em}\hspace{0.17em}}\text{Angiosome}}-\text{E}{\text{T}}_{\text{right}\mathrm{\hspace{0.17em}\hspace{0.17em}}\text{Angiosome}}\right|.\end{array}$ …”

A review of the effectiveness of thermal infrared imaging in the diagnosis and monitoring of knee diseases

“…A similar study was carried out by Glehr et al [37] on 13 subjects (eight subjects with anterior knee pain at the retinaculum patellae and five subjects with anterior knee pain following knee prosthesis). In this study, the infrared images from frontal, inner and outer locations were acquired with a Thermacam PM595 system that works in (À40 to 500)°C temperature range and in (7.5-13) lm spectral range.…”

Examining an image reconstruction method in infrared emission tomography

“…Two widely used reconstruction techniques are employed in this study to solve the image reconstruction problem defined in Equation 6 and provide reference images for comparison are the Algebraic Reconstruction Technique (ART) and the Maximum Likelihood Expectation Maximization (MLEM) method. ART [30,31] and MLEM [32,33] are well established and widely used methods in emission tomography, although MLEM invariably yields superior results and it is widely regarded as representing the "State of the Art" method.…”

“…ART [30,31] and MLEM [32,33] are well established and widely used methods in emission tomography, although MLEM invariably yields superior results and it is widely regarded as representing the "State of the Art" method. Both methods are capable of incorporating the projection model of Equation 6 and can provide reconstruction results using sets containing a limited number of planar projections [34]. In the present work, the Newton-Raphson variant of ART [35] and an accelerated version of MLEM [36] were used for the reconstruction of the tomographic images.…”