Technical skill is crucial in the use of thermography to evaluate saddle fit and possible medical conditions in horses. Thermography,
or the use of infrared imaging, allows a real-time evaluation of the temperature gradient in the peripheral body (Photos 1
and 2). Areas of increased heat can indicate metabolic activity, increased blood supply or the possibility of an inflammatory
process. Decreased heat can indicate vascular damage or nerve involvement. Saddles are excellent heat conductors and allow
visualization of the contact points after only a relatively short amount of time being ridden.
Photo 1: In a thermography scan of a saddle, the color scale goes from black (coldest and least contact, pressure or heat)
to white (hottest and most contact or pressure). This rider has a chronic right knee problem and cannot ride in a balanced
way. He puts more weight on the right side because he cannot post out of the saddle with that knee, which twists the saddle
so you see increased heat on the entire right side. This horse had a sore back and was sore in his right girth and chest area.
Because there is such a potential for artifacts to be seen while producing thermographic evaluations and for mistakes to be
made in interpretation, it is crucial that a knowledgeable and experienced individual produce and evaluate the scans. Thermography
has the advantage of producing both pre- and post-exercise scans, which can show a substantial change in affected areas.
Photo 2: This thermography scan shows a saddle with increased contact, pressure and heat on the withers area and hardly any
contact on the back of the saddle. This is an example of a bridging problem—as this saddle rocks back and forth, it will pinch
the withers and shorten stride and cause soreness. Occasionally these horses are presented for evaluation of a complaint of
increased tripping in front.
As more veterinarians add newer modalities such as thermographic imaging and pressure pad sensor gait analysis to their practices,
it will become easier to determine the location and exact cause of various medical conditions or to decide that it is indeed
time to go saddle shopping. When this topic is revisited in the future, maybe there will be more agreement among horse owners,
saddle fitters and veterinarians as to the effects of saddle fit on equine performance and behavior. As all parties become
more aware and educated, we can hope that better choices will be made for saddle fit and the percentage of horses being ridden
while in pain can be drastically reduced.
Dr. Kenneth Marcella is an equine practitioner in Canton, Ga.
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3. Meschan EM, Peham C, Schobesberger H, et al. The influence of the width of the saddle tree on the forces and the pressure
distribution under the saddle. Vet J 2007;173:578-584.
4. Cockerman S. Saddle fit study in the Western saddle market. Las Cruces: New Mexico State University Press, 2010.