Since the late 1990's use of thermography has increased in both finding and preventing causes of lameness. Originally used mainly with race horses and show animals, current usage has expanded in many veterinary practices.
Thermography is a non-invasive technique, whereby a camera with a sensor measures the infra-red emissions from a horse’s body. Once the information is recorded, it enters the camera and the temperature variations are depicted in the display with different colors corresponding to different temperatures.
Essentially the sensors see into the horse’s body,enabling the veterinarian to compare one leg or one site with another. After images are recorded in the camera they are then downloaded into a computer that analyzes the data and generates a report which indicates the relevance of the temperature variations.
The reason that heat detection is important is because the presence of heat is considered one of the cardinal signs of inflammation. The human hand is able to appreciate, in some circumstances, a change in temperature of 1.0 degrees C, while this camera can detect changes down to 0.1 degrees C, a ten-fold improvement. In addition to heat, the camera will also appreciate cold areas.
Heat or inflammation is generally a result from hemorrhage, external or internal trauma, tendon or joint inflammation and/or infection. Conversely, cold may be seen with decreased circulation, non-active swelling such as edema or in the presence of obstruction of blood flow.
Many applications for this technology exist in equine practice. It can be used for early lameness detection, hoof balance, saddle fit, back soreness, and any lameness condition that may involve joints, muscles and/or tendons. It has a role in almost all aspects of soundness evaluation.
The ability to diagnose a mild unevenness before it becomes an active clinical problem is of immense benefit. There are many early soft tissue - tendon, muscle or ligament - injuries that are not apparent until they become more active and difficult to manage.
Many veterinarians are equipping their facilities with heat detection cameras and programs. Although the cameras and programs can be quite expensive, they can be rented by the day or week, making them available to a broad spectrum of horse owners.