Infrared Thermography as a Means of Monitoring and Preventing Sports Injuries

Sports injuries are one of the most important problems in sports. Moreover, professional sports injuries lead to a difficult recovery process for the athletes, reduced athletic performance, and large economic costs. Infrared thermography (IRT) is a safe, non-invasive and low-cost technique that allows for the rapid and non-contact recording of Skin Temperature (Tsk). Recent research results have demonstrated new applications for this technique; among them, the monitoring and prevention of sports injuries appears to be one of the most interesting applications. Although IRT is not as objective as other methods, it may be sufficiently accurate and reliable as a complementary tool considering the theory that musculoskeletal structures should be in thermal equilibrium when in a healthy state. Therefore, the main contribution of IRT is to help identify an injury before it occurs, providing an opportunity for preventative action.

Cooling Agents' Effect Monitoring When Applied to Skin of Healthy Human Subjects

There are cooling products available for relieving the pain of minor sports injuries, in muscles, tendons, joints, strains, sprains and knocks. These products are based on ice, gel and cold patches. In order to quantify objectively the effect of each type of those products thermal imaging was used. This monitoring method is suitable to quantify quickly large regions of interest in skin areas over time through the thermal radiation perceived by thermal camera sensors. All recorded images were taken in a controlled environment and following a standard capture protocol in terms of subject, equipment and examination room preparation and procedure of conduction the examination. Two experiments were performed. The obtained results demonstrate that quantitative thermal imaging is a simple and objective tool for evaluating topical cooling treatments. However, it is important to assess the emissivity of any applied substance, which could have a significant effect on temperature measurement by remote sensing.

Clinical Applications

The study of the diagnostic accuracy of Infrared Thermal Imaging in the diagnosis of orthopaedic injuries in childhood has been motivated by the high incidence of these injuries throughout the world, being one of the most common reasons for urgent medical consultation. Diagnosis of musculoskeletal injuries usually involves radiography, but this exposes children without fractures to unnecessary ionising radiation. This chapter assesses whether infrared thermography could provide a viable alternative in cases of trauma. To evaluate the accuracy of this technique new thermographic variables have been added to those commonly analysed, such as the extent of the injury and the difference in the size of the area that is at an equal temperature or higher than the maximum temperature of the healthy area. Non-linear cataloguing methods (decision tree models) have also been applied. With the protocol presented, infrared thermal imaging had a sensitivity of 0.91, a specificity of 0.88 and a negative predictive value of 0.95 for diagnosing musculoskeletal injuries.

Thermal Imaging in Evaluation of the Physical Fitness Level

The thermoregulation mechanisms during the physical effort can be easily study by using the thermovision. The thermoregulation mechanisms in human body keep the body core temperature on basic level 37 ± 2oC. However, the question is if there are any differences in skin surface temperature distribution between trainee sportsmen and amateur. Is there any possibility to show the sportsman level of practise using the thermal imaging? Would it be possible to evaluate the efficiency of athlete or evaluate the level of sports possibilities in average amateur who just wants to start cycle training. To find how the thermoregulation mechanisms work the different measurements were done i.e. during the cyclist endurance test for group of male cyclist (intermediate level of cycling skill) and during the Aerobic Circuit Training (ACT) for trainee and amateur group of women.

Thermographic Evaluation of Racehorse Performance

Thermography has found a broad range of applications in equine sport and veterinary medicine. Thermographic diagnosis is useful in monitoring changes of horse surface temperature resulting from exercise allowing evaluation of the work of individual parts of the body in racing performance. Regular assessment of body surface temperature allows the detection of training overloads and identification of pathological conditions of the musculoskeletal system during the racing training cycle. The usefulness of thermography in veterinary medicine has been proved in detecting pathological conditions associated mainly with inflammation processes of the distal parts of the limbs and back. The main advantage of thermography is the detection of subclinical signs of inflammation before the onset of clinical signs of pathology, providing great value in veterinary medicine diagnosis. Thermography has also found application in detecting illegal performance procedures to improve horse performance and in assessing the saddle fit to the horse's back.

Thermography in Animal Models of Cancer

Laboratory animals provide important models for studying human diseases, including many types of cancer. Mice are among the most commonly used laboratory animals, allowing for the study of carcinogenic agents, cancer development and for testing innovative preventive and therapeutic strategies. Thus, monitoring angiogenesis in animal models is a major goal for cancer research. Among the currently available imaging techniques, thermography is a useful approach for studying the superficial vascularization of cancer, based on their heat emissions. At this chapter emphasis is placed on thermography and its applications on laboratory animals, in comparison with other available and applicable imaging techniques. In conclusion, thermography may be usefully applied to the study of cancer vascularization in animal models, particularly when using laboratory rodents such as mice. Care is needed in adapting existing approaches to the specificities of each animal species.

Thermal Diagnostics in Chronic Venous Disease

The aim of the study was to determine the diagnostic usefulness of thermal imaging as tool to find quantitative parameters in lower-limb primary chronic venous diseases and insufficiency of superficial veins. There were significant differences obtained in thermal maps of lower extremities between patients and healthy. The correlations were obtained between temperature parameters counted from thermal imaging and duplex scanning. Such results also suggest that thermovision diagnostics may be useful as a complementary and first of all objective method that can be used in the diagnosis of chronic venous diseases in the lower extremities. It may suggest that thermovision may be used as a screening method or together with an ultrasound diagnosis in different superficial veins disorders.

Infrared Thermography in Swimming

In order to verify whether there is a considerable increase in body skin temperature during different swimming techniques (crawl and backstroke) and identifying the most affected regions. The athlete's thermal symmetry was also analyzed, as well as its modification after the swimming, according to the performed technique. The accuracy of thermography as a method to identify and distinguish these different styles was also evaluated. Ten male swimmers were recruited and two different swimming techniques were assessed, crawl and backstroke. After a 10 minute acclimatization period in the pool, the swimmers were quickly dried with microfiber towels. The thermograms were taken before and after the swimming task, which consisted in a 7x200m protocol in crawl or backstroke. Infrared thermography revealed an increase of temperature after exercise and no significant differences were found between both techniques. Thermal symmetry was not affected by exercise.

Development of a Clinical Microvascular Imaging and Vascular Optics Facility

The Newcastle Microvascular Diagnostics Service (MDS) provides a comprehensive array of optical and thermal technologies for assessing micro-circulatory blood flow and function. Thermography is a key modality, although the facility has capability for capillaroscopy, laser Doppler perfusion / speckle contrast imaging, as well as numerous non-imaging techniques. The test portfolio covers four main areas: connective tissue disease and Raynaud's phenomenon, specialist limb studies (i.e. amputation level, muscle compartment perfusion and venous physiology), neurovascular assessment, and burn wound depth assessment. The MDS greatly benefits from a state-of-the-art temperature and humidity-controlled clinical room, enabling thermal physiology investigations to be performed efficiently and with confidence. Extensive research and development (R&D) is also undertaken, with collaborations across a range of academic, clinical and industrial partners. This chapter summarizes the history and development of the MDS, tests performed, R&D undertaken, clinical management, and future service directions.

Thermal Imaging

This chapter describes an approach to quantifying the local inflammatory response at the injection site after a vaccination by infrared imaging. The aim is to develop a thermographic procedure providing support to evaluate the reactivity of a vaccine. The development of the experimental design had to consider an optimum timeframe for infrared imaging, the variability of the local thermal emission, questions regarding the thermal left-right symmetry and further biometric aspects. To verify this concept, more than 80 participants of the influenza vaccination campaign were involved. Even if this study is based on a well-tolerated seasonal influenza vaccination, nearly 40% of all subjects show a pronounced thermal reaction of approximately 1°C. Apart from this, 25-30% displays no signs of any thermal response. The question of how far thermal imaging will contribute to facilitating the assessment of the reactivity of a vaccine has several aspects which are discussed in this chapter.